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There is ample evidence that motor sequence learning is mediated by changes in brain activity. Yet the question of whether this form of learning elicits changes detectable at the spinal cord level has not been addressed. To date, studies in humans have revealed that spinal reflex activity may be altered during the acquisition of various motor skills, but a link between motor sequence learning and changes in spinal excitability has not been demonstrated. To address this issue, we studied the modulation of H-reflex amplitude evoked in the flexor carpi radialis muscle of 14 healthy individuals between blocks of movements that involved the implicit acquisition of a sequence versus other movements that did not require learning. Each participant performed the task in three conditions: "sequence"-externally triggered, repeating and sequential movements, "random"-similar movements, but performed in an arbitrary order, and "simple"- involving alternating movements in a left-right or up-down direction only. When controlling for background muscular activity, H-reflex amplitude was significantly more reduced in the sequence (43.8 +/- 1.47%. mean +/- SE) compared with the random (38.2 +/- 1.60%) and simple (31.5 +/- 1.82%) conditions, while the M-response was not different across conditions. Furthermore, H-reflex changes were observed from the beginning of the learning process up to when subjects reached asymptotic performance on the motor task. Changes also persisted for >60 s after motor activity ceased. Such findings suggest that the excitability in some spinal reflex circuits is altered during the implicit learning process of a new motor sequence.

The current and potential uses of neuroimaging in healthcare and beyond have spurred discussion about the ethical issues related to neuroimaging and neuroimaging research. This study examined the perspectives of neuroimagers on ethical issues in their research and on the ethics review process. One hundred neuroimagers from 13 Canadian neuroscience centers completed an online survey and 35 semi-structured interviews were conducted. Neuroimagers felt that most ethical and social issues identified in the literature were dealt with adequately, well, and even very well by research ethics boards (REBs), but some issues such as incidental findings and transfer of knowledge were problematic. Neuroimagers reported a range of practical problems in the ethics review process. We aimed to gather perspectives from REB on the ethics review process, but insufficient participation by REBs prevented us from reporting their perspectives. Given shortcomings identified by neuroimagers as well as longstanding issues in Canadian ethics governance, we believe that substantial challenges exist in Canadian research ethics governance that jeopardize trust, communication, and the overall soundness of research ethics governance. Neuroimagers and REBs should consider their shared responsibilities in developing guidance to handle issues such as incidental findings, risk assessment, and knowledge transfer.

Motor skill learning is associated with profound changes in brain activation patterns over time. Associative and rostral premotor cortical and subcortical regions are mostly recruited during the early phase of explicit motor learning, while sensorimotor regions may increase their activity during the late learning phases. Distinct brain networks are therefore engaged during the early and late phases of motor skill learning. How these regions interact with one another and how information is transferred from one circuit to the other has been less extensively studied. In this study, we used functional MRI (fMRI) at 3T to follow the changes in functional connectivity in the associative/premotor and the sensorimotor networks, during extended practice (4 weeks) of an explicitly known sequence of finger movements. Evolution of functional connectivity was assessed using integration, a measure that quantifies the total amount of interaction within a network. When comparing the integration associated with a complex finger movement sequence to that associated with a simple sequence, we observed two patterns of decrease during the 4 weeks of practice. One was not specific as it was observed for all sequences, whereas a specific decrease was observed only for the execution of the learned sequence. This second decrease was a consequence of a relative decrease in associative/premotor network integration, together with a relative increase in between-network integration. These findings are in line with the hypothesis that information is transferred from the associative/premotor circuit to the sensorimotor circuit during the course of motor learning.

The 'learning and performance' conundrum has for a long time puzzled the field of cognitive neuroscience. Deciphering the genuine functional neuroanatomy of motor sequence learning, among that of other skills, has thereby been hampered. The main caveat is that changes in neural activity that inherently accompany task practice may not only reflect the learning process per se, but also the basic motor implementation of improved performance. Previous research has attempted to control for a performance confound in brain activity by adopting methodologies that prevent changes in performance. However, blocking the expression of performance is likely to distort the very nature of the motor sequence learning process, and may thus represent a major confound in itself. In the present study, we postulated that both learning-dependent plasticity mechanisms and learning-independent implementation processes are nested within the relationship that exists between performance and brain activity. Functional magnetic resonance imaging (fMRI) was used to map brain responses in healthy volunteers while they either (a) learned a novel sequence, (b) produced a highly automatized sequence or (c) executed non-sequential movements matched for speed frequency. In order to dissociate between qualitatively distinct, but intertwined, relationships between performance and neural activity, our analyses focused on correlations between variations in performance and brain activity, and how this relationship differs or shares commonalities between conditions. Results revealed that activity in the putamen and contralateral lobule VI of the cerebellum most strongly correlated with performance during learning per se, suggesting their key role in this process. By contrast, activity in a parallel cerebellar network, as well as in motor and premotor cortical areas, was modulated by performance during learning and during one or both control condition(s), suggesting the primary contribution of these areas in motor implementation, either as a function or not of the sequential content of movements. Our findings thus highlight the multifaceted nature of the link between performance and brain activity, and suggest that different components of the striato-cortical and cerebello-cortical motor loops play distinct, but complementary, roles during early motor sequence learning.

Background and Purpose: : The additional effects of combining mental practice with a small amount of physical practice on the relearning of a motor task post-stroke are unknown. This study investigated the added value of mental practice on the relearning of rising up from a chair and sitting down when combined with a small amount of physical practice., Methods: : Twelve individuals with chronic stroke were randomly assigned to one of three groups: a group that combined mental practice with physical practice (MP), a group that combined physical practice with cognitive training (Cog) and a group without training (NOT.). Training was provided three times per week for four weeks, and participants were assessed at baseline, after training, and three weeks later. The vertical forces were recorded under each foot, and the vertical impulse was calculated for five trials and converted in percent of body weight., Results: : The MP and Cog groups received the same amount of physical training. Significant gains (P < 0.04) in limb loading found only in the MP group were retained. Larger (P < 0.03) change scores in limb loading for rising up from a chair and sitting down were found in the MP group (median = rising up: 18.4%; sitting down: 12.2%) compared with Cog group (median = rising up: -6.8%; sitting down: 5.4%) and a group without training (median = rising up: 6.2%; sitting down: 5.4%)., Conclusion: : Combining series of mental repetitions ( approximately 1100 repetitions) with minimal physical repetitions ( approximately 120 repetitions) yielded significant gains and retention of those gains. These preliminary results provide some support to the added value of combining mental repetitions with a small number of physical repetitions to promote the relearning of motor strategies post-stroke and warrant further investigation in clinical trials.

Objective: To study the effects of sensory modality of simultaneous tasks during walking with and without obstacles after moderate to severe traumatic brain injury (TBI)., Design: Group comparison study., Setting: Gait analysis laboratory within a postacute rehabilitation facility., Participants: Volunteer sample (N=18). Persons with moderate to severe TBI (n=11) (9 men, 3 women; age, 37.56+/-13.79 y) and a comparison group (n=7) of subjects without neurologic problems matched on average for body mass index and age (4 men, 3 women; age, 39.19+/-17.35 y)., Interventions: Not applicable., Main Outcome Measures: Magnitudes and variability for walking speeds, foot clearance margins (ratio of foot clearance distance to obstacle height), and response reaction times (both direct and as a relative cost because of obstacle avoidance)., Results: The TBI group had well-recovered walking speeds and a general ability to avoid obstacles. However, these subjects did show lower trail limb toe clearances (P=.003) across all conditions. Response reaction times to the Stroop tasks were longer in general for the TBI group (P=.017), and this group showed significant increases in response reaction times for the visual modality within the more challenging obstacle avoidance task that was not observed for control subjects. A measure of multitask costs related to differences in response reaction times between obstructed and unobstructed trials also only showed increased attention costs for the visual over the auditory stimuli for the TBI group (P=.002)., Conclusions: Mobility is a complex construct, and the present results provide preliminary findings that, even after good locomotor recovery, subjects with moderate to severe TBI show residual locomotor deficits in multitasking. Furthermore, our results suggest that sensory modality is important, and greater multitask costs occur during sensory competition (ie, visual interference).

Task-induced deactivation is frequently reported in the ventro-medial prefrontal cortex (vmPFC) and posterior cingulate cortex (PCC), regions considered to belong to the default mode network. To investigate the effect of dopamine on task-induced deactivation, we used positron emission tomography to measure cerebral blood flow during performance of the Tower of London task before and after administration of the dopamine receptor agonist apomorphine in six healthy volunteers (49-66 years old) and six Parkinson disease patients (52-69 years old). Although task-induced deactivation was observed in the vmPFC and PCC in both groups and in both conditions, an inverse correlation between activation and problem complexity was observed in the vmPFC only in the apomorphine condition.

Although there is ample evidence that motor imagery activates similar cerebral regions to those solicited during actual movements, it is still unknown whether visual (VI) and kinesthetic imagery (KI) recruit comparable or distinct neural networks. The present study was thus designed to identify, through functional magnetic resonance imaging at 3.0 Tesla in 13 skilled imagers, the cerebral structures implicated in VI and KI. Participants were scanned in a perceptual control condition and while physically executing or focusing during motor imagery on either the visual or kinesthetic components of an explicitly known sequence of finger movements. Subjects' imagery abilities were assessed using well-established psychological, chronometric, and new physiological measures from the autonomic nervous system. Compared with the perceptual condition, physical executing, VI, and KI resulted in overlapping (albeit non-identical) brain activations, including motor-related regions and the inferior and superior parietal lobules. By contrast, a divergent pattern of increased activity was observed when VI and KI were compared directly: VI activated predominantly the occipital regions and the superior parietal lobules, whereas KI yielded more activity in motor-associated structures and the inferior parietal lobule. These results suggest that VI and KI are mediated through separate neural systems, which contribute differently during processes of motor learning and neurological rehabilitation., (Copyright 2009 Wiley-Liss, Inc)

Although there is ample evidence that motor imagery (MI) improves motor performance after CNS injury, it is still unknown whether MI may enhance motor recovery after peripheral injury and most especially in the rehabilitation of burn patients. This study aimed to investigate the effects of a 2-week MI training program combined with conventional rehabilitation on the recovery of motor functions in handed burn patients. Fourteen patients admitted to the Medical Burn Center were requested to take part in the study and were randomly assigned to the imagery or the control group. Behavioral data related to the ability to perform each successive step of three manual motor sequences were collected at five intervals during the medical procedure. The results provided evidence that MI may facilitate motor recovery, and the belief in the effectiveness of MI was strong in all patients. MI may substantially contribute to improve the efficacy of conventional rehabilitation programs. Hence, this technique should be considered as a reliable alternative method to help burn patients to recover motor functions.

Background: The ability to generate vivid images of movements is variable across individuals and likely influenced by sensorimotor inputs., Objectives: The authors examined (1) the vividness of motor imagery in dancers and in persons with late blindness, with amputation or an immobilization of one lower limb; (2) the effects of prosthesis use on motor imagery; and (3) the temporal characteristics of motor imagery., Methods: Eleven dancers, 10 persons with late blindness, 14 with amputation, 6 with immobilization, and 2 groups of age-matched healthy individuals (27 in control group A; 35 in control group B) participated. The Kinesthetic and Visual Imagery Questionnaire served to assess motor imagery vividness. Temporal characteristics were assessed with mental chronometry., Results: The late blindness group and dance group displayed higher imagery scores than respective control groups. In the amputation and immobilization groups, imagery scores were lower on the affected side than the intact side and specifically for imagined foot movements. Imagery scores of the affected limb positively correlated with the time since walking with prosthesis. Movement times during imagination and execution (amputation and immobilization) were longer on the affected side than the intact side, but the temporal congruence between real and imagined movement times was similar to that in the control group., Conclusions: The mental representation of actions is highly modulated by imagery practice and motor activities. The ability to generate vivid images of movements can be specifically weakened by limb loss or disuse, but lack of movement does not affect the temporal characteristics of motor imagery.

There is increasing evidence supporting the notion that the contribution of sleep to consolidation of motor skills depends on the nature of the task used in practice. We compared the role of three post-training conditions in the expression of delayed gains on two different motor skill learning tasks: finger tapping sequence learning (FTSL) and visuomotor adaptation (VMA). Subjects in the DaySleep and ImmDaySleep conditions were trained in the morning and at noon, respectively, afforded a 90-min nap early in the afternoon and were re-tested 12 h post-training. In the NightSleep condition, subjects were trained in the evening on either of the two learning paradigms and re-tested 12 h later following sleep, while subjects in the NoSleep condition underwent their training session in the morning and were re-tested 12 h later without any intervening sleep. The results of the FTSL task revealed that post-training sleep (day-time nap or night-time sleep) significantly promoted the expression of delayed gains at 12 h post-training, especially if sleep was afforded immediately after training. In the VMA task, however, there were no significant differences in the gains expressed at 12 h post-training in the three conditions. These findings suggest that "off-line" performance gains reflecting consolidation processes in the FTSL task benefit from sleep, even a short nap, while the simple passage of time is as effective as time in sleep for consolidation of VMA to occur. They also imply that procedural memory consolidation processes differ depending on the nature of task demands.

This review discusses the cerebral plasticity, and the role of the cortico-striatal system in particular, observed as one is learning or planning to execute a newly learned motor behavior up to when the skill is consolidated or has become highly automatized. A special emphasis is given to imaging work describing the neural substrate mediating motor sequence learning and motor adaptation paradigms. These results are then put into a plausible neurobiological model of motor skill learning, which proposes an integrated view of the brain plasticity mediating this form of memory at different stages of the acquisition process.

Recent studies of functional connectivity based upon blood oxygen level dependent functional magnetic resonance imaging have shown that this technique allows one to investigate large-scale functional brain networks. In a previous study, we advocated that data-driven measures of effective connectivity should be developed to bridge the gap between functional and effective connectivity. To attain this goal, we proposed a novel approach based on the partial correlation matrix. In this study, we further validate the use of partial correlation analysis by employing a large-scale, neurobiologically realistic neural network model to generate simulated data that we analyze with both structural equation modeling (SEM) and the partial correlation approach. Unlike real experimental data, where the interregional anatomical links are not necessarily known, the links between the nodes of the network model are fully specified, and thus provide a standard against which to judge the results of SEM and partial correlation analyses. Our results show that partial correlation analysis from the data alone exhibits patterns of effective connectivity that are similar to those found using SEM, and both are in agreement with respect to the underlying neuroarchitecture. Our findings thus provide a strong validation for the partial correlation method.

A wide range of experimental studies have provided evidence that a night of sleep may enhance motor performance following physical practice (PP), but little is known, however, about its effect after motor imagery (MI). Using an explicitly learned pointing task paradigm, thirty participants were assigned to one of three groups that differed in the training method (PP, MI, and control groups). The physical performance was measured before training (pre-test), as well as before (post-test 1) and after a night of sleep (post-test 2). The time taken to complete the pointing tasks, the number of errors and the kinematic trajectories were the dependent variables. As expected, both the PP and the MI groups improved their performance during the post-test 1. The MI group was further found to enhance motor performance after sleep, hence suggesting that sleep-related effects are effective following mental practice. Such findings highlight the reliability of MI in learning process, which is thought consolidated when associated with sleep.

Functional magnetic resonance imaging (fMRI) of the spinal cord has been the subject of intense research for the last ten years. An important motivation for this technique is its ability to detect non-invasively neuronal activity in the spinal cord related to sensorimotor functions in various conditions, such as after spinal cord lesions. Although promising results of spinal cord fMRI have arisen from previous studies, the poor reproducibility of BOLD activations and their characteristics remain a major drawback. In the present study we investigated the reproducibility of BOLD fMRI in the spinal cord of cats (N=9) by repeating the same stimulation protocol over a long period (approximately 2 h). Cats were anaesthetized with ketamine, and spinal cord activity was induced by electrical stimulation of cutaneous nerves of the hind limbs. As a result, task-related signals were detected in most cats with relatively good spatial specificity. However, BOLD response significantly varied within and between cats. This variability was notably attributed to the moderate intensity of the stimulus producing a low amplitude haemodynamic response, variation in end-tidal CO(2) during the session, low signal-to-noise ratio (SNR) in spinal fMRI time series and animal-specific vascular anatomy. Original contributions of the present study are: (i) first spinal fMRI experiment in ketamine-anaesthetized animals, (ii) extensive study of intra- and inter-subject variability of activation, (iii) characterisation of static and temporal SNR in the spinal cord and (iv) investigation on the impact of CO(2) end-tidal level on the amplitude of BOLD response.

Beyond the reading-related deficits typical of developmental dyslexia (DD), recent evidence suggests that individuals afflicted with this condition also show difficulties in motor sequence learning. To date, however, little is known with respect to the characteristics of the learning impairments, nor to the neural correlates associated with this type of procedural deficit in DD patients. Here, we first summarize the results of the few behavioral and brain imaging studies that have investigated the effects of DD on motor sequence learning. To help guide research in this field, we then discuss relevant psychophysical and neuroimaging work conducted in healthy volunteers in relation to three different conceptual perspectives: when, how, and what. More specifically, we examine the cognitive boundaries that affect performance across the different stages of learning (i.e., "when"), the different cognitive processes (i.e., "how") under which learning occurs, and the mental representations (i.e., "what") that are elicited when acquiring this type of skilled behavior. It is hoped that this conceptual framework will be useful to researchers interested in further studying the nature of the motor learning impairment reported in DD.

While cognitive skill learning is normally acquired implicitly through frontostriatal circuitry in healthy individuals, neuroimaging studies suggest that patients with Parkinson's disease (PD) do so by activating alternate, intact brain areas associated with explicit memory processing. To further test this hypothesis, 10 patients with PD and 12 healthy controls were tested on a modified, learning version of the Tower of London task while undergoing positron emission tomography at four different time points over the course of learning. Despite having less accurate problem solving abilities than controls, PD patients were able to acquire the skill learning task. However, as compared to controls, they maintained higher levels of cerebral blood flow activity in the dorsolateral prefrontal cortex and hippocampus and showed an increase in activity in the frontopolar cortex and posterior cingulate over the course of learning. These findings reflect a shift to the explicit memory system in PD patients, enabling them to learn this cognitive skill, which is normally acquired by control subjects using implicit learning strategies and frontostriatal circuitry.

The interaction between CC chemokine receptor 2 (CCR2) with monocyte chemoattractant proteins, such as MCP-1, regulates the activation and recruitment of inflammatory leukocytes. In this study, we characterized (S)-3-[3,4-difluoro-phenyl)-propyl]-5-isoxazol-5-yl-2-thioxo-2,3-dihydro-1H-imidazole-4-carboxyl acid methyl ester (JNJ-27141491) as a noncompetitive and orally active functional antagonist of human (h)CCR2. JNJ-27141491 strongly suppressed hCCR2-mediated in vitro functions, such as MCP-1-induced guanosine 5'-O-(3-[(35)S]thio)triphosphate binding; MCP-1, -3, and -4-induced Ca(2+) mobilization; and leukocyte chemotaxis toward MCP-1 (IC(50) = 7-97 nM), whereas it had little or no effect on the function of other chemokine receptors tested. The inhibition of CCR2 function was both insurmountable and reversible, consistent with a noncompetitive mode of action. JNJ-27141491 blocked the binding of (125)I-MCP-1 to human monocytes (IC(50) = 0.4 microM), but it failed to affect MCP-1 binding to mouse, rat, and dog cells (IC(50) > 10 microM). Therefore, transgenic mice, in which the mouse (m)CCR2 gene was replaced by the human counterpart, were generated for in vivo testing. In these mice, oral administration of JNJ-27141491 dose-dependently [5-40 mg/kg q.d. (once daily) or b.i.d.] inhibited monocyte and neutrophil recruitment to the alveolar space 48 h after intratracheal mMCP-1/lipopolysaccharide instillation. Furthermore, treatment with JNJ-27141491 (20 mg/kg q.d.) significantly delayed the onset and temporarily reduced neurological signs in an experimental autoimmune encephalomyelitis model of multiple sclerosis. Taken together, these results identify JNJ-27141491 as a noncompetitive, functional antagonist of hCCR2, capable of exerting oral anti-inflammatory activity in transgenic hCCR2-expressing mice.

In neuroscience, the notion has emerged that the brain abides by two principles: segregation and integration. Segregation into functionally specialized systems and integration of information flow across systems are basic principles that are thought to shape the functional architecture of the brain. A measure called integration, originating from information theory and derived from mutual information, has been proposed to characterize the global integrative state of a network. In this paper, we show that integration can be applied in a hierarchical fashion to quantify functional interactions between compound systems, each system being composed of several regions. We apply this method to fMRI datasets from patients with low-grade glioma and show how it can efficiently extract information related to both intra- and interhemispheric reorganization induced by lesional brain plasticity.

Although numerous behavioural studies provide evidence that there exist wide differences within individual motor imagery (MI) abilities, little is known with regards to the functional neuroanatomical networks that dissociate someone with good versus poor MI capacities. For the first time, we thus compared, through functional magnetic resonance imaging (fMRI), the pattern of cerebral activations in 13 skilled and 15 unskilled imagers during both physical execution and MI of a sequence of finger movements. Differences in MI abilities were assessed using well-established questionnaire and chronometric measures, as well as a new index based upon the subject's peripheral responses from the autonomic nervous system. As expected, both good and poor imagers activated the inferior and superior parietal lobules, as well as motor-related regions including the lateral and medial premotor cortex, the cerebellum and putamen. Inter-group comparisons revealed that good imagers activated more the parietal and ventrolateral premotor regions, which are known to play a critical role in the generation of mental images. By contrast, poor imagers recruited the cerebellum, orbito-frontal and posterior cingulate cortices. Consistent with findings from the motor sequence learning literature and Doyon and Ungerleider's model of motor learning [Doyon, J., Ungerleider, L.G., 2002. Functional anatomy of motor skill learning. In: Squire, L.R., Schacter, D.L. (Eds.), Neuropsychology of memory, Guilford Press, pp. 225-238], our results demonstrate that compared to skilled imagers, poor imagers not only need to recruit the cortico-striatal system, but to compensate with the cortico-cerebellar system during MI of sequential movements.

Objective: The aim of this study was to investigate: (1) the effects of a stroke on motor imagery vividness as measured by the Kinesthetic and Visual Imagery Questionnaire (KVIQ-20); (2) the influence of the lesion side; and (3) the symmetry of motor imagery., Methods: Thirty-two persons who had sustained a stroke, in the right (n = 19) or left (n = 13) cerebral hemisphere, and 32 age-matched healthy persons participated. The KVIQ-20 assesses on a 5-point ordinal scale the clarity of the image (visual scale) and the intensity of the sensations (kinesthetic scale) that the subjects are able to imagine from the first-person perspective., Results: In both groups, the visual scores were higher (P = .0001) than the kinesthetic scores and there was no group difference. Likewise, visual scores remained higher than kinesthetic scores irrespective of the lesion side. The visual scores poststroke were higher (P = .001) when imagining upper limb movements on the unaffected side than those on the affected side. When focusing on the lower limb only, however, the kinesthetic scores were higher (P = .001) when imagining movements of the unaffected compared to those on the affected side., Conclusions: The vividness of motor imagery poststroke remains similar to that of age-matched healthy persons and is not affected by the side of the lesion. However, after stroke motor imagery is not symmetrical and motor imagery vividness is better when imagining movements on the unaffected than on the affected side, indicating an overestimation possibly related to a hemispheric imbalance or a recalibration of motor imagery perception.

We recently reported the discovery of a series of 2-thioimidazoles as CCR2 antagonists. The most potent molecules of this series, the 4,5-diesters, were rapidly hydrolyzed to the inactive acids and were found to be metabolically unstable. Herein we describe the synthesis of a number of analogues with heterocyclic bioisosteric replacements of the ester group(s). Small 5-membered heterocyclic substituents at the 4-position gave highly potent CCR2 antagonists. Hydrolysis of the 5-ester is diminished, thus imparting these compounds with sufficient stability and systemic exposure after oral administration to warrant further study of the in vivo pharmacology of these functional CCR2 inhibitors.

Researchers realize that motor imagery (MI) duration is closely linked to actual motor action duration. In 2 experiments, the authors investigated the effect of changing MI speed on actual movement duration over a 3-week training period. Experiment 1 involved 2 series of body movements that 24 participants mentally performed faster or slower than their actual execution speeds. The fast MI group's actual times decreased on subsequent performance. Participants in Experiment 2 were 21 skilled athletes who increased (decreased) their well-rehearsed actual movement times after MI training at a slow (fast) speed. The effect was task-related, however: MI affected only self-initiated movement. The effect of MI on actual speed execution supports the ideomotor theory because anticipation of sensory consequences of actions is mentally represented.

Object: Resection of brain tumors has been shown to increase patient survival. The extent of the possible resection, however, depends on whether the tumor has invaded brain regions important for motor, sensory, or cognitive processes and whether the brain tissue surrounding the tumor maintains its functional role. The goal of the present study was to develop new pre- and intraoperative tools to specifically assess the function of the rostral part of the dorsal premotor cortex (PMdr) in 4 patients with brain tumors close to this region., Methods: Using functional magnetic resonance (fMR) imaging and a task developed to assess accurate selection between competing responses based on conditional rules, the authors preoperatively assessed the function of the PMdr in 4 patients with brain tumors close to this region. In 1 patient, the authors developed an intraoperative procedure to assess performance on the task during the tumor resection., Results: Preoperative fMR imaging data showed specific activity increases in the vicinity of the tumors, that is, in the PMdr. As confirmed by postoperative structural MR imaging, the extent of the tumor resection was optimal and the functional region within the PMdr was preserved. Furthermore, patients exhibited no postoperative deficits during task performance, demonstrating that the function was preserved. Intraoperative behavioral results demonstrated that the cognitive processes underlying performance on the task remained intact throughout the tumor resection., Conclusions: These findings suggest that preoperative fMR imaging, together with intraoperative behavioral evaluation, may be a useful paradigm to assist neurosurgeons in preserving cognitive function in patients with brain tumors.

Objective: To examine the reproducibility of 2 chronometric tests: time-dependent motor imagery (TDMI) screening test and temporal congruence test., Design: Test-retest 10 to 14 days apart., Setting: Laboratory of a university-affiliated center for research in rehabilitation., Participants: Twenty persons post cerebrovascular accident (CVA) and 46 healthy persons (controls)., Intervention: The reproducibility of the TDMI screening test, wherein the number of stepping movements (performed in sitting) imagined over 15, 25, and 45 seconds is recorded, and of the temporal congruence test wherein the duration of physically executed (E) and imagined (I) stepping movements is recorded, was evaluated., Main Outcome Measures: The test-retest reliability of the number of imagined movements (TDMI screening test), movement duration and I/E time ratios (temporal congruence test), and intrasession reliability of the temporal congruence test were assessed by using intraclass correlation coefficients (ICCs)., Results: For the TDMI screening test, the ICCs ranged from .88 to .93 (CVA, n=20) and from .87 to .92 (controls, n=9). For the temporal congruence test, when the total duration of 2 series of 5 stepping movements was averaged, ICCs ranged from .76 to .97 (CVA, n=20) and from .77 to .93 (controls, n=46), whereas for 1 series the ICCs ranged from .71 to .95 and from .63 to .95 in the CVA and control groups, respectively. The ICCs for intrasession reliability for the CVA (n=20) and control (n=46) groups, respectively, ranged from .90 to .98 and .95 to .97., Conclusions: The present findings support the reproducibility of both tests in both groups. Mental chronometry can be used reliably for the screening of patients capable of motor imagery or for measuring temporal congruence between real and imagined movements poststroke.

As care needs continue to increase in complexity in inpatient settings, and nurses' scope of practice evolves to keep pace with these changing demands, it is imperative that nurse leaders ensure nursing care delivery models are well aligned to current realities. Older, traditional models of nursing service may no longer foster safe, effective and efficient care or contribute to job satisfaction and high-quality work life for nurses. This paper describes the Autonomous-Collaborative Care Model and its application in a continuing care setting. This innovative and flexible model fosters autonomy and accountability in nursing practice, reduces duplication in the execution of nursing tasks, enhances effective communication and outlines mechanisms for collaboration among various members of the nursing and interprofessional teams. The model has positioned the authors' organization to meet impending shortages of nursing personnel by ensuring that the right category of nurse is assigned to the appropriate patient, by reducing non-nursing work and by supporting nurses' autonomy to practise to their full scope.

Noninvasive techniques such as functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) have provided insight into understanding how neural connections are altered in consequence to cerebrovascular injury. The first part of this review will briefly survey some of the methodological issues and limitations related to noninvasive poststroke motor recovery studies. The second section will investigate some of the different neural mechanisms that underlie neurorehabilitation in stroke patients. The third part will explore our current understanding of motor memory processing, describe the neural structures that subserve motor memory consolidation, and discuss the current literature related to memory reconsolidation in healthy adults. Lastly, this paper will suggest the potential therapeutic applications of integrating noninvasive tools with memory consolidation and reconsolidation theories to enhance motor recovery. The overall objective of this work is to demonstrate how noninvasive technologies have been utilized in the multidisciplinary field of clinical behavioral neuroscience and to highlight their potential to be employed as clinical tools to promote individualized motor recovery in stroke patients.

Due to its non-invasive nature and low cost, diffuse optical imaging (DOI) is becoming a commonly used technique to assess functional activation in the brain. When imaging with DOI, two major issues arise in the data analysis: (i) the separation of noise of physiological origin and the recovery of the functional response; (ii) the tomographic image reconstruction problem. This paper focuses on the first issue. Although the general linear model (GLM) has been extensively used in functional magnetic resonance imaging (fMRI), DOI has mostly relied on filtering and averaging of raw data to recover brain functional activation. This is mainly due to the high temporal resolution of DOI which implies a new design of the drift basis modelling physiology. In this paper, we provide (i) a filtering method based on cosine functions that is more adapted than standard averaging techniques for DOI specifically; (ii) a new mode-locking technique to recover small signals and locate them temporally with high precision (shift method). Results on real data show the capability of the shift method to retrieve HbR and HbO(2) peak locations.

Objective: To assess the relationship between the presence of REM sleep behavior disorder (RBD) and the cognitive profile of nondemented patients with Parkinson disease (PD)., Background: Cognitive impairment is an important nonmotor symptom in PD. Waking EEG slowing in nondemented PD has been related to the presence of RBD, a parasomnia affecting brainstem structures and frequently reported in PD. For this reason, RBD may be associated with cognitive impairment in PD., Methods: Thirty-four patients with PD (18 patients with polysomnographic-confirmed RBD and 16 patients without RBD) and 25 healthy control subjects matched for age and educational level underwent sleep laboratory recordings and a comprehensive neuropsychological assessment., Results: Patients with PD and concomitant RBD showed significantly poorer performance on standardized tests measuring episodic verbal memory, executive functions, as well as visuospatial and visuoperceptual processing compared to both patients with PD without RBD and control subjects. Patients with PD without RBD had no detectable cognitive impairment compared to controls., Conclusions: This study shows that cognitive impairment in nondemented patients with Parkinson disease (PD) is closely related to the presence of REM sleep behavior disorder, a sleep disturbance that was not controlled for in previous studies assessing cognitive deficits in PD.

In functional magnetic resonance imaging (fMRI) data analysis, effective connectivity investigates the influence that brain regions exert on one another. Structural equation modeling (SEM) has been the main approach to examine effective connectivity. In this paper, we propose a method that, given a set of regions, performs partial correlation analysis. This method provides an approach to effective connectivity that is data driven, in the sense that it does not require any prior information regarding the anatomical or functional connections. To demonstrate the practical relevance of partial correlation analysis for effective connectivity investigation, we reanalyzed data previously published [Bullmore, Horwitz, Honey, Brammer, Williams, Sharma, 2000. How good is good enough in path analysis of fMRI data? NeuroImage 11, 289-301]. Specifically, we show that partial correlation analysis can serve several purposes. In a pre-processing step, it can hint at which effective connections are structuring the interactions and which have little influence on the pattern of connectivity. As a post-processing step, it can be used both as a simple and visual way to check the validity of SEM optimization algorithms and to show which assumptions made by the model are valid, and which ones should be further modified to better fit the data.

This study was designed to gain more insight into the mechanisms underlying motor imagery (MI). While there is ample evidence that motor performance and MI share common central neural mechanisms, the question whether MI is accompanied by subliminal electromyographic (EMG) activity remained unsolved. Thirty right-handed volunteers were asked to lift or to imagine lifting a weighted dumbbell using different types of muscle contraction, i.e. heavy concentric, light concentric, isometric and eccentric contractions. EMG activity from 9 muscles of the dominant arm (agonist, antagonist, synergist and fixator muscles) was monitored. Autonomic nervous system responses were also recorded on the non-dominant hand, thus attesting mental activity at the peripheral level. A significant increased pattern of EMG activity was recorded in all muscles during MI, when compared to the rest condition, while the goniometric data did not reveal any movement. Although being subliminal, the magnitude of this activation was found to be correlated to the mental effort required to lift a weight mentally, as more EMG activity was recorded during imaginary lifting of heavy than light concentric contractions. When considering the different types of contraction, our results provided evidence of selective changes in EMG activity. Especially, the imagined eccentric condition elicited a significant weaker muscular activity than all other conditions. In addition, the changes in the EMG pattern mirrored those usually observed during physical movement. These findings support the hypotheses of a selective effect of MI at the level of muscular activity and of incomplete inhibition of the motor command during MI.

Two behavioral phenomena characterize human motor memory consolidation: diminishing susceptibility to interference by a subsequent experience and the emergence of delayed, offline gains in performance. A recent model proposes that the sleep-independent reduction in interference is followed by the sleep-dependent expression of offline gains. Here, using the finger-opposition sequence-learning task, we show that an interference experienced at 2 h, but not 8 h, following the initial training prevented the expression of delayed gains at 24 h post-training. However, a 90-min nap, immediately post-training, markedly reduced the susceptibility to interference, with robust delayed gains expressed overnight, despite interference at 2 h post-training. With no interference, a nap resulted in much earlier expression of delayed gains, within 8 h post-training. These results suggest that the evolution of robustness to interference and the evolution of delayed gains can coincide immediately post-training and that both effects reflect sleep-sensitive processes.

Purpose: To benefit from mental practice training after stroke, one must be able to engage in motor imagery, and thus reliable motor imagery assessment tools tailored to persons with sensorimotor impairments are needed. The aims of this study were to (1) examine the test-retest reliability of the Kinesthetic and Visual Imagery Questionnaire (KVIQ-20) and its short version (the KVIQ-10) in healthy subjects and subjects with stroke, (2) investigate the internal consistency of both KVIQ versions, and (3) explore the factorial structure of the two KVIQ versions., Methods: The KVIQ assesses on a five-point ordinal scale the clarity of the image (visual: V subscale) and the intensity of the sensations (kinesthetic: K subscale) that the subjects are able to imagine from the first-person perspective. Nineteen persons who had sustained a stroke (CVA group) and 46 healthy persons (CTL group) including an age-matched (aCTL: n = 19) control group were assessed twice by the same examiner 10 to 14 days apart. The test-retest reliability was assessed using intraclass correlation coef- ficients (ICCs). The internal consistency (Cronbach alpha) and the factorial structure of both KVIQ versions were studied in a sample of 131 subjects., Results: In the CVA group, the ICCs ranged from 0.81 to 0.90, from 0.73 to 0.86 in the aCTL group, and from 0.72 to 0.81 in the CTL group. When imagining movements of the affected and unaffected limbs (upper and lower limbs combined) ICCs in the CVA group ranged, respectively, from 0.71 to.87 and from 0.86 to 0.94. Likewise, when imagining movement of the dominant and nondominant limbs, ICCs in the aCTL group ranged, respectively, from 0.75 to 0.89 and from 0.81 to.92. Cronbach a values were, respectively, 0.94 (V) and 0.92 (K) for the KVIQ-20 and 0.89 (V) and 0.87(K) for the KVIQ-10. The factorial analyses indicated that two factors explained 63.4% and 67.7% of total variance, respectively., Conclusion: Both versions of the KVIQ present similar psychometric properties that support their use in healthy individuals and in persons post-stroke. Because the KVIQ-10 can be administered in half the time, however, it is a good choice when assessing persons with physical disabilities.

Primary Objective: To determine the relationships between clinical measures of executive function and attention, and laboratory measures of anticipatory locomotor adaptations with dual tasks following a TBI., Methods and Procedures: Ten people with moderate or severe TBI were compared to 10 healthy subjects for neuropsychological measures in the clinic, as well as locomotor patterns and reading time in the laboratory for adapted Stroop tasks (Bar and Word) during unobstructed and obstructed walking., Main Outcomes and Results: As previously found 1 (Vallee M, McFadyen BJ, Swaine B, Doyon J, Cantin JF, Dumas D. Effects of environmental demands on locomotion after traumatic brain injury. Archives of Physical Medicine Rehabilitation 2006;87:806--813) during the locomotor activities, subjects with TBI walked slower, had higher clearance margins and took longer to read during the Stroop tasks than healthy subjects. In general, subjects with TBI also showed deficits in executive functions and attention. Significant relationships were specifically observed between scores on Trail Making B and clearance margins for subjects with TBI, but not for healthy subjects. Alternatively, significant relationships between clinical scores on Stroop and dual task Stroop reading times were obtained for healthy subjects but not for subjects with TBI., Conclusions: These results suggest that measures of executive functioning and attention may be associated to locomotor behaviour in complex environments following a moderate to severe TBI.

When applied to functional magnetic resonance imaging (fMRI) data, spatial independent component analysis (sICA), a data-driven technique that addresses the blind source separation problem, seems able to extract components specifically related to physiological noise and brain movements. These components should be removed from the data to achieve structured noise reduction and improve any subsequent detection and analysis of signal fluctuations related to neural activity. We propose a new automatic method called CORSICA (CORrection of Structured noise using spatial Independent Component Analysis) to identify the components related to physiological noise, using prior information on the spatial localization of the main physiological fluctuations in fMRI data. As opposed to existing spectral priors, which may be subject to aliasing effects for long-TR data sets (typically acquired with TR >1 s), such spatial priors can be applied to fMRI data, regardless of the TR of the acquisitions. By comparing the proposed automatic selection to a manual selection performed visually by a human operator, we first show that CORSICA is able to identify the noise-related components for long-TR data with a high sensitivity and a specificity of 1. On short-TR data sets, we validate that the proposed method of noise reduction allows a substantial improvement of the signal-to-noise ratio evaluated at the cardiac and respiratory frequencies, even in the gray matter, while preserving the main fluctuations related to neural activity.

The absolute configurations of two precursors, that is, 1-(3',4'-dichlorophenyl)-propanol and 1-(3',4'-dichlorophenyl)-propanamine, of a potent 2-mercapto-imidazole CCR-2 receptor antagonist, JNJ-27553292, were determined using vibrational circular dichroism. As a consequence, the absolute configuration of the antagonist itself was also determined. The two precursor compounds were subjected to a thorough conformational analysis and rotational strengths were calculated at the B3LYP/cc-pVTZ level of theory. Based on these data, vibrational circular dichroism spectra were simulated, which in turn were compared with experimental spectra. Agreement between the spectra allowed the assignment of the absolute configuration, which is in agreement with the proposed configuration based on stereospecific reactions on similar compounds.

Examination of functional interactions through effective connectivity requires the determination of three distinct levels of information: (1) the regions involved in the process and forming the spatial support of the network, (2) the presence or absence of interactions between each pair of regions, and (3) the directionality of the existing interactions. While many methods exist to select regions (Step 1), very little is available to complete Step 2. The two main methods developed so far, structural equation modeling (SEM) and dynamical causal modeling (DCM), usually require precise prior information to be used, while such information is sometimes lacking. Assuming that Step 1 was successfully completed, we here propose a data-driven method to deal with Step 2 and extract functional interactions from fMRI datasets through partial correlations. Partial correlation is more closely related to effective connectivity than marginal correlation and provides a convenient graphical representation for functional interactions. As an instance of brain interactivity investigation, we consider how simple hand movements are processed by the bihemispheric cortical motor network. In the proposed framework, Bayesian analysis makes it possible to estimate and test the partial statistical dependencies between regions without any prior model on the underlying functional interactions. We demonstrate the interest of this approach on real data.

Objective: To determine the effects of increasingly demanding environments related to simultaneous visual tasks and physical obstructions on the locomotor ability of people with traumatic brain injury (TBI)., Design: Group comparison study., Setting: Gait analysis laboratory within a postacute rehabilitation facility., Participants: Volunteer sample of 9 people (8 men, 1 woman; age, 39.3+/-13.0y) with moderate to severe TBI and a comparison group of 9 subjects without neurologic problems matched for age and sex (8 men, 1 woman; age, 39.7+/-12.3y)., Interventions: Not applicable., Main Outcome Measures: Reading times for the Stroop bar and Stroop word tasks, walking speeds, stride lengths, and obstacle clearance margin., Results: The TBI group was slower than the control group in performing the Stroop bar task during sitting (P=.002), and while avoiding the narrow obstacle (P=.05), and in performing the Stroop word task while avoiding the wide obstacle (P=.019). Despite their relatively normal gait speeds on level ground, subjects with TBI walked more slowly than control subjects for the narrow (P=.024) and the wide (P=.019) obstacle conditions and for the most complex dual task (P=.042). Greater lead-limb clearance margins were observed for the TBI group than for control subjects for all conditions whereas no differences were found for the trail limb except at the far end of the wide obstacle., Conclusions: Despite their good recovery of locomotor function, with respect to normal level walking speeds and ability to avoid obstacles, subjects with moderate and severe TBI showed residual deficits in relation to greater difficulties in dealing with environments that challenge their locomotor and attentional abilities. The use of such naturally based dual tasks may help identify some of the environmental obstructions to social participation after TBI.

In the present study, we have investigated the effect of (i) ET-1 (endothelin-1) and its precursor, big ET-1, on MMP (matrix metalloproteinase)-2 and MMP-9 synthesis and activity in osteosarcoma tissue, and (ii) ET-1 receptor antagonists on cell invasion. Using Western blotting, zymography, RT-PCR (reverse transcription-PCR), immunohistochemistry, immunofluorescence and Northern blotting, we have shown that ET-1 and ET-1 receptors (ET(A) and ET(B)) were expressed in these cells. Additionally, we have demonstrated that ET-1 markedly induced the synthesis and activity of MMP-2, which was significantly increased when compared with MMP-9. Furthermore, inhibition of NF-kappaB (nuclear factor kappaB) activation blocked MMP-2 production and activity, indicating the involvement of NF-kappaB, a ubiquitous transcription factor playing a central role in the differentiation, proliferation and malignant transformation. Since ET-1 acts as an autocrine mediator through gelatinase induction and because inhibition of ET(A) receptor is beneficial for reducing both basal and ET-1-induced osteosarcoma cell invasion, targeting this receptor could be an attractive therapeutic alternative for the successful treatment of osteosarcoma.

Rapid-eye-movement (REM) sleep behaviour disorder (RBD) is characterised by loss of muscular atonia and prominent motor behaviours during REM sleep. RBD can cause sleep disruption and severe injuries for the patient or bed partner. The disorder is strongly associated with neurodegenerative diseases, such as multiple-system atrophy, Parkinson's disease, dementia with Lewy bodies, and progressive supranuclear palsy. In many cases, the symptoms of RBD precede other symptoms of these neurodegenerative disorders by several years. Furthermore, several recent studies have shown that RBD is associated with abnormalities of electroencephalographic activity, cerebral blood flow, and cognitive, perceptual, and autonomic functions. RBD might be a stage in the development of neurodegenerative disorders and increased awareness of this could lead to substantial advances in knowledge of mechanisms, diagnosis, and treatment of neurodegenerative disorders.

Cognition is thought to result from interactions within large-scale networks of brain regions. Here, we propose a method to identify these large-scale networks using functional magnetic resonance imaging (fMRI). Regions belonging to such networks are defined as sets of strongly interacting regions, each of which showing a homogeneous temporal activity. Our method of large-scale network identification (LSNI) proceeds by first detecting functionally homogeneous regions. The networks of functional interconnections are then found by comparing the correlations among these regions against a model of the correlations in the noise. To test the LSNI method, we first evaluated its specificity and sensitivity on synthetic data sets. Then, the method was applied to four real data sets with a block-designed motor task. The LSNI method correctly recovered the regions whose temporal activity was locked to the stimulus. In addition, it detected two other main networks highly reproducible across subjects, whose activity was dominated by slow fluctuations (0-0.1 Hz). One was located in medial and dorsal regions, and mostly overlapped the "default" network of the brain at rest [Greicius, M.D., Krasnow, B., Reiss, A.L., Menon, V., 2003. Functional connectivity in the resting brain: a network analysis of the default mode hypothesis. Proceedings of the National Academy of Sciences of the U.S.A. 100, 253-258]; the other was composed of lateral frontal and posterior parietal regions. The LSNI method we propose allows to detect in an exploratory and systematic way all the regions and large-scale networks activated in the working brain.

In this study, we used functional MRI (fMRI) at high field (3T) to track the time course of activation in the entire basal ganglia circuitry, as well as other motor-related structures, during the explicit learning of a sequence of finger movements over a month of training. Fourteen right-handed healthy volunteers had to practice 15 min daily a sequence of eight moves using the left hand. MRI sessions were performed on days 1, 14 and 28. In both putamen, activation decreased with practice in rostrodorsal (associative) regions. In contrast, there was a significant signal increase in more caudoventral (sensorimotor) regions of the putamen. Subsequent correlation analyses between signal variations and behavioral variables showed that the error rate (movement accuracy) was positively correlated with signal changes in areas activated during early learning, whereas reaction time (movement speed) was negatively correlated with signal changes in areas activated during advanced learning stages, including the sensorimotor putamen and globus pallidus. These results suggest the possibility that motor representations shift from the associative to the sensorimotor territories of the striato-pallidal complex during the explicit learning of motor sequences, suggesting that motor skills are stored in the sensorimotor territory of the basal ganglia that supports a speedy performance.

We used positron emission tomography (PET) to examine within-day learning of timed motor sequences. The results of this experiment are novel in showing an interaction between cerebellum and primary motor cortex (M1) during learning that appears to be mediated by the dentate nucleus (DN) and in demonstrating that activity in these regions is directly related to performance. Subjects were scanned during learning (LRN) across three blocks of practice and during isochronous (ISO) and perceptual (PER) baseline conditions. CBF was compared across blocks of learning and between the LRN and baseline conditions. Results demonstrated an interaction between the cerebellum and M1 such that earlier, poorer performance was associated with greater activity in the cerebellar hemispheres and later, better performance was associated with greater activity in M1. Inter-regional correlation analyses confirmed that as CBF in the cerebellum decreases, blood flow in M1 increases. Importantly, these analyses also revealed that activity in cerebellar cortex was positively correlated with activity in right DN and that DN activity was negatively correlated with blood flow in M1. Activity in the cerebellar hemispheres early in learning is likely related to error correction mechanisms which optimize movement kinematics resulting in improved performance. Concurrent DN activity may be related to encoding of this information and DN output to M1 may play a role in consolidation processes that lay down motor memories. Increased activity in M1 later in learning may reflect strengthening of synaptic connections associated with changes in motor maps that are characteristic of learning in both animals and humans.

On the basis of brain imaging studies, Doyon and Ungerleider recently proposed a model describing the cerebral plasticity that occurs in both cortico-striatal and cortico-cerebellar systems of the adult brain during learning of new motor skilled behaviors. This theoretical framework makes several testable predictions with regards to the contribution of these neural systems based on the phase (fast, slow, consolidation, automatization, and retention) and nature of the motor learning processes (motor sequence versus motor adaptation) acquired through repeated practice. There has been recent behavioral, lesion and additional neuroimaging studies that have addressed the assumptions made in this theory that will help in the revision of this model.

Motor skills, once learned, need to be consolidated over time in order to become resistant to disruption or interference. In some instances, the consolidation phase can also include spontaneous gains in performance even in the absence of further rehearsal on a motor task. Clinical and behavioral evidence suggest that N-methyl-D-aspartate (NMDA)-receptor activity is required for motor learning acquisition and behavioral synaptic plasticity. However, the involvement of NMDA receptors in motor consolidation, leading to stabilization of the recently formed motor memory, has not yet been assessed in humans. To address this issue, we used post-training administration of amantadine, a low-affinity NMDA-receptor channel blocker. In a double-blind design, 200 mg of amantadine or a matching placebo was given orally to two different groups of 11 healthy young volunteers each. The subjects were tested twice 24 h apart, using a motor adaptation paradigm consisting of an eight-target-pointing task. Comparison of the mean performance levels on this task revealed that subjects in both groups improved their performance levels significantly on Day 2 compared to Day 1, regardless of the treatment administered. Our data indicate that amantadine failed to block motor learning consolidation in subjects that had already learned the motor adaptation task. Thus, although required in some stages (e.g. acquisition) of motor memory processes, the present results suggest that NMDA-receptor activation may not be essential for consolidation of motor adaptation in humans.

We describe the synthesis and SAR of a new class of CCR2 antagonists based on 2-mercaptoimidazole scaffold. The initial lead 1a was optimized to the 3,4-disubstituted analogues 1p-(S) and 1q-(S), which have IC(50) values in the MCP-1 induced Ca-flux below 0.01 microM.

Trichogramma are facultative gregarious egg parasitoids that attack a wide range of lepidopterous eggs. Because hosts in which parasitoids develop vary in terms of available food, the progeny produced by parasitoid females vary in size and fitness. While one might expect that the developmental rate and emergence rhythm should be similar for all individuals reared under the same environmental conditions, variations in the duration of development of individuals reared under uniform conditions have been found in several insect species. In the Hymenopteran egg parasitoid Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae) adults emerge at the beginning of the photoperiod on two consecutive days. Longer development may influence the fitness of adults and have an impact on mating opportunities. Size, longevity and daily and lifetime fecundity were measured for female T. evanescens that developed in nine and ten days. We observed a significant relationship between size and both longevity and lifetime fecundity. While early emerging females did not live longer and did not produce progeny with a different sex-ratio than females that emerged later, they were larger and produced more progeny than late females. We conclude that early emerging females have a higher fitness than late emerging females T. evanescens.

A computerized version of the Tower of London task was used to investigate cognitive skill learning. Thirty-six healthy volunteers were assigned to either a random condition (nonrecurring problems), or to a sequence condition in which, unbeknownst to the subjects, a repeating sequence of three problems was presented. Indices of execution, planning, and total time, as well as number of moves performed, were used to measure behavioural change. Subjects' performance improved in both conditions across blocks of practice. A distinct learning effect related to the repeating sequence was also observed. This suggests that a specific skill that reflects procedural learning of the strategies, rules, and procedures pertaining to repeating problems can develop over and above a more general skill at solving cognitive planning problems with practice.