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Background: One of the more challenging daily‐life actions for Parkinson's disease patients is starting to stand from a sitting position. Parkinson's disease patients are known to have difficulty with self‐initiated movements and benefit from external cues. However, the brain processes underlying external cueing as an aid remain unknown. The advent of mobile electroencephalography (EEG) now enables the investigation of these processes in dynamic sit‐to‐stand movements. Objective: To identify cortical correlates of the mechanisms underlying auditory cued sit‐to‐stand movement in Parkinson's disease. Methods: Twenty‐two Parkinson's disease patients and 24 healthy age‐matched participants performed self‐initiated and externally cued sit‐to‐stand movements while cortical activity was recorded through 32‐channel mobile EEG. Results: Overall impaired integration of sensory and motor information can be seen in the Parkinson's disease patients exhibiting less modulation in the θ band during movement compared to healthy age‐matched controls. How Parkinson's disease patients use external cueing of sit‐to‐stand movements can be seen in larger high β power over sensorimotor brain areas compared to healthy controls, signaling sensory integration supporting the maintenance of motor output. This appears to require changes in cognitive processing to update the motor plan, reflected in frontal θ power increases in Parkinson's disease patients when cued. Conclusion: These findings provide the first neural evidence for why and how cueing improves motor function in sit‐to‐stand movement in Parkinson's disease. The Parkinson's disease patients' neural correlates indicate that cueing induces greater activation of motor cortical areas supporting the maintenance of a more stable motor output, but involves the use of cognitive resources to update the motor plan. © 2024 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Leaf spot is considered as a common disease of oil palm, caused primarily by Curvularia spp. fungi. This disease mainly affects the early stages of oil palm and if not adequately controlled can cause plant death. Among the methods available to control the disease, breeding resistant varieties is the most economically effective and promising strategy. A genome‐wide association study for leaf spot resistance was conducted on 210 individual tenera palms from seven different (origin) crosses. These palms were subsequently infected with Curvularia spp. pathogenic inoculum in a nursery trial located in an endemic area. The area under the disease progress curve was used as a phenotypic measure. In addition, a genotyping‐by‐sequencing (GBS) approach was used to obtain the genotyping data of each individual. We found two loci, at chromosome 2 and chromosome 13, that were significantly associated with leaf spot disease resistance. Six genetic variants at the two loci (five variants at chromosome 2 and one variant at chromosome 13) surpassed the threshold for genome‐wide significance (p < 106). These loci are linked with three widely known disease‐related genes, namely, resistance gene analogue 3 (RGA3), resistance gene analogue 4 (RGA4) and receptor‐like protein 9a (RLP9a). The loci identified here can be used for marker‐assisted selection when developing leaf spot disease‐resistant oil palm varieties. [ABSTRACT FROM AUTHOR]

Recent brain imaging research demonstrates that the use of internal visual imagery (IVI) or kinesthetic imagery (KIN) activates common and distinct brain areas. In this paper, we argue that combining the imagery modalities (IVI and KIN) will lead to a greater cognitive representation (with more brain areas activated), and this will cause a greater slalom-based motor performance compared with using IVI alone. To examine this assertion, we randomly allocated 56 participants to one of the three groups: IVI, IVI and KIN, or a math control group. Participants performed a slalom-based driving task in a driving simulator, with average lap time used as a measure of performance. Results revealed that the IVI and KIN group achieved significantly quicker lap times than the IVI and the control groups. The discussion includes a theoretical advancement on why the combination of imagery modalities might facilitate performance, with links made to the cognitive neuroscience literature and applied practice. [ABSTRACT FROM AUTHOR]

The ability to safely negotiate the world on foot takes humans years to develop, reflecting the extensive cognitive demands associated with real‐time planning and control of walking. Despite the importance of walking, methodological limitations mean that surprisingly little is known about the neural and cognitive processes that support ambulatory motor control. Here, we report mobile EEG data recorded from 32 healthy young adults during real‐world ambulatory obstacle avoidance. Participants walked along a path while stepping over expected and unexpected obstacles projected on the floor, allowing us to capture the dynamic oscillatory response to changes in environmental demands. Compared to obstacle‐free walking, time–frequency analysis of the EEG data revealed clear neural markers of proactive and reactive forms of movement control (occurring before and after crossing an obstacle), visible as increases in frontal theta and centro‐parietal beta power respectively. Critically, the temporal profile of changes in frontal theta allowed us to arbitrate between early selection and late adaptation mechanisms of proactive control. Our data show that motor plans are updated as soon as an upcoming obstacle appears, rather than when the obstacle is reached. In addition, regardless of whether motor plans required updating, a clear beta rebound was present after obstacles were crossed, reflecting the resetting of the motor system. Overall, mobile EEG recorded during real‐world walking provides novel insight into the cognitive and neural basis of dynamic motor control in humans, suggesting new routes to the monitoring and rehabilitation of motor disorders such as dyspraxia and Parkinson's disease. [ABSTRACT FROM AUTHOR]

A genetically modified (GM) commercial corn variety, MON810, resistant to European corn borer, has been shown to be non-toxic to mammals in a number of rodent feeding studies carried out in accordance with OECD Guidelines. Insect resistance results from expression of the Cry1Ab gene encoding an insecticidal Bt protein that causes lysis and cell death in susceptible insect larvae by binding to midgut epithelial cells, which is a key determinant of Cry toxin species specificity. Whilst whole animal studies are still recognised as the 'gold standard' for safety assessment, they only provide indirect evidence for changes at the cellular/organ/tissue level. In contrast, omics-based technologies enable mechanistic understanding of toxicological or nutritional events at the cellular/receptor level. To address this important knowledge-gap and to gain insights into the underlying molecular responses in rat to MON810, differential gene expression in the epithelial cells of the small intestine of rats fed formulated diets containing MON810, its near isogenic line, two conventional corn varieties, and a commercial (Purina™) corn-based control diet were investigated using comparative proteomic profiling. Pairwise and five-way comparisons showed that the majority of proteins that were differentially expressed in the small intestine epithelial cells in response to consumption of the different diets in both 7-day and 28-day studies were related to lipid and carbohydrate metabolism and protein biosynthesis. Irrespective of the diet, a limited number of stress-related proteins were shown to be differentially expressed. However these stress-related proteins differed between diets. No adverse clinical or behavioural effects, or biomarkers of adverse health, were observed in rats fed GM corn compared to the other corn diets. These findings suggest that MON810 has negligible effects on the small intestine of rats at the cellular level compared with the well-documented toxicity observed in susceptible insects. [ABSTRACT FROM AUTHOR]

Objective Patients with hemineglect fail to respond to egocentric stimuli or allocentric parts of stimuli contralateral to the brain lesion. The clinical diagnosis of hemineglect mainly involves evaluation of the egocentric form, while less sensitive standardized tests exist for other forms. Our global aim is to develop an innovative integrative robot measure, the MonAmour test, combining the assessment of egocentric, allocentric and motor hemineglect. Here, we present the egocentric and allocentric evaluations. Methods Thirty-five first stroke patients (25 hemineglect) and 56 age-matched healthy controls were assessed on the index test (MonAmour) and on three reference standard tests (Bells test, Apples test and Neglect subtest of the Test for Attentional Performance). Based on controls' performance, normative data were created. Validity was evaluated between the MonAmour and the reference standard tests through correlations and test sensitivity/specificity. Reliability of the MonAmour was measured with test–retest and minimal detectable change. Results Results demonstrated moderate to strong correlations between the MonAmour and the reference standard tests (r =.40–.88, p <.001 – p =.016). The sensitivity was high (50%–96%), with accurate diagnosis of patients with hemineglect, and reliability was excellent (Intraclass Correlation Coefficient =.79–.95, p <.001). Conclusions The MonAmour robot test is a valid, sensitive and reliable tool that can diagnose egocentric and allocentric hemineglect. Future studies will deepen the assessment and understanding of the different forms of hemineglect by testing the motor component of the test in order to use this accurate and integrative measure in daily clinical routine. Registration ClinicalTrials.gov(NCT02543424). [ABSTRACT FROM AUTHOR]

Plants have co-evolved with a diverse array of pathogens and insect herbivores and so have evolved an extensive repertoire of constitutive and induced defence mechanisms activated through complex signalling pathways. OXI1 kinase is required for activation of mitogen-activated protein kinases (MAPKs) and is an essential part of the signal transduction pathway linking oxidative burst signals to diverse downstream responses. Furthermore, changes in the levels of OXI1 appear to be crucial for appropriate signalling. Callose deposition also plays a key role in defence. Here we demonstrate, for the first time, that OXI1 plays an important role in defence against aphids. The Arabidopsis mutant, oxi1-2, showed significant resistance both in terms of population build-up (p < 0.001) and the rate of build-up (p < 0.001). Arabidopsis mutants for β-1,3-glucanase, gns2 and gns3, showed partial aphid resistance, significantly delaying developmental rate, taking two-fold longer to reach adulthood. Whilst β-1,3-glucanase genes GNS1, GNS2, GNS3 and GNS5 were not induced in oxi1-2 in response to aphid feeding, GNS2 was expressed to high levels in the corresponding WT (Col-0) in response to aphid feeding. Callose synthase GSL5 was up-regulated in oxi1-2 in response to aphids. The results suggest that resistance in oxi1-2 mutants is through induction of callose deposition via MAPKs resulting in ROS induction as an early response. Furthermore, the results suggest that the β-1,3-glucanase genes, especially GNS2, play an important role in host plant susceptibility to aphids. Better understanding of signalling cascades underpinning tolerance to biotic stress will help inform future breeding programmes for enhancing crop resilience. [ABSTRACT FROM AUTHOR]

BACKGROUND The neurotoxin peptide ω- ACTX-Hv1a, fused to the carrier molecule GNA, presents potential for insect control as a biopesticide, being orally toxic to insect pests from different orders. However, thorough evaluation is required to assure its safety towards non-target invertebrates. Effects of this novel biopesticide on the parasitoid Eulophus pennicornis via its host Lacanobia oleracea are presented. RESULTS Hv1a/ GNA did not cause mortality when injected or fed to fifth-stage L. oleracea, but caused up to 39% reduction in mean larval weight ( P < 0.05) and increased developmental time when injected. When fed, GNA, but not Hv1a/ GNA, caused ∼35% reduction in larval weight, indicating that host quality was not affected by the fusion protein. Although GNA and Hv1a/ GNA were internalised by the hosts following ingestion, and thus were available to higher trophic levels, no significant changes in the rate of E. pennicornis parasitism occurred. Number of parasitoid pupae per host, adult emergence and sex ratio were unaffected by GNA- or Hv1a/ GNA-treated hosts ( P > 0.05). The fusion protein was degraded by parasitoid larvae, rendering it non-toxic. CONCLUSION Hv1a/ GNA has negligible effects on the parasitoid, even under worst-case scenarios. This low toxicity to these insects is of interest in terms of biopesticide specificity and safety to non-target organisms. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Patients with apraxia perform poorly when demonstrating how an object is used, particularly when pantomiming the action. However, these patients are able to accurately identify, and to pick up and move objects, demonstrating intact ventral and dorsal stream visuomotor processing. Appropriate object manipulation for skilled use is thought to rely on integration of known and visible object properties associated with "ventro-dorsal" stream neural processes. In apraxia, it has been suggested that stored object knowledge from the ventral stream may be less readily available to incorporate into the action plan, leading to an over-reliance on the objects' visual affordances in object-directed motor behavior. The current study examined grasping performance in left hemisphere stroke patients with (N = 3) and without (N = 9) apraxia, and in age-matched healthy control participants (N = 14), where participants repeatedly grasped novel cylindrical objects of varying weight distribution. Across two conditions, object weight distribution was indicated by either a memory-associated cue (object color) or visual-spatial cue (visible dot over the weighted end). Participants were required to incorporate object-weight associations to effectively grasp and balance each object. Control groups appropriately adjusted their grasp according to each object's weight distribution across each condition, whereas throughout the task two of the three apraxic patients performed poorly on both the memory-associated and visual-spatial cue conditions. A third apraxic patient seemed to compensate for these difficulties but still performed differently to control groups. Patients with apraxia performed normally on the neutral control condition when grasping the evenly weighted version. The pattern of behavior in apraxic patients suggests impaired integration of visible and known object properties attributed to the ventro-dorsal stream: in learning to grasp the weighted object accurately, apraxic patients applied neither pure knowledge-based information (the memory-associated condition) nor higher-level information given in the visual-spatial cue condition. Disruption to ventro-dorsal stream predicts that apraxic patients will have difficulty learning to manipulate new objects on the basis of information other than low-level visual cues such as shape and size. [ABSTRACT FROM AUTHOR]

In three experiments, we investigated Hebb repetition learning (HRL) differences between children and adults, as a function of the type of item (lexical vs. sub-lexical) and the level of item-overlap between sequences. In a first experiment, it was shown that when non-repeating and repeating (Hebb) sequences of words were all permutations of the same words, HRL was slower than when the sequences shared no words. This item-overlap effect was observed in both children and adults. In a second experiment, we used syllable sequences and we observed reduced HRL due to item-overlap only in children. The findings are explained within a chunking account of the HRL effect on the basis of which we hypothesize that children, compared with adults, chunk syllable sequences in smaller units. By hypothesis, small chunks are more prone to interference from anagram representations included in the filler sequences, potentially explaining the item-overlap effect in children. This hypothesis was tested in a third experiment with adults where we experimentally manipulated the chunk size by embedding pauses in the syllable sequences. Interestingly, we showed that imposing a small chunk size caused adults to show the same behavioral effects as those observed in children. Departing from the analogy between verbal HRL and lexical development, the results are discussed in light of the less-is-more hypothesis of age-related differences in language acquisition. [ABSTRACT FROM AUTHOR]

An introduction is presented to a section within the issue regarding the mechanisms involved in the mental practice of action and mentally representing action using the motor system.

The perception of reachability (i.e., whether an object is within reach) relies on body representations and action simulation. Similarly, egocentric distance estimation (i.e., the perception of the distance an object is from the self) is thought to be partly derived from embodied action simulation. Although motor simulation is important for both, it is unclear whether the cognitive processes underlying these behaviors rely on the same motor processes. To investigate this, we measured the impact of a motor interference dual-task paradigm on reachability judgment and egocentric distance estimation, while allocentric length estimation (i.e., how distant two stimuli are from each other independent from the self) was used as a control task. Participants were required to make concurrent actions with either hand actions of foam ball grip squeezing or arm actions of weight lifting, or no concurrent actions. Results showed that concurrent squeeze actions significantly slowed response speed in the reachability judgment and egocentric distance estimation tasks, but that there was no impact of the concurrent actions on allocentric length estimation. Together, these results suggest that reachability and distance perception, both egocentric perspective tasks, and in contrast to the allocentric perspective task, involve action simulation cognitive processes. The results are discussed in terms of the implication of action simulation when evaluating the position of a target relative to the observer's body, supporting an embodied view of spatial cognition. [ABSTRACT FROM AUTHOR]

Action priming following action observation is thought to be caused by the observed action kinematics being represented in the same brain areas as those used for action execution. But, action priming can also be explained by shared goal representations, with compatibility between observation of the agent's gaze and the intended action of the observer. To assess the contribution of action kinematics and eye-gaze cues in the prediction of an agent's action goal and action priming, participants observed actions where the availability of both cues was manipulated. Action observation was followed by action execution, and the congruency between the target of the agent's and observer's actions, and the congruency between the observed and executed action spatial location were manipulated. Eye movements were recorded during the observation phase, and the action priming was assessed using motion analysis. The results showed that the observation of gaze information influenced the observer's prediction speed to attend to the target, and that observation of action kinematic information influenced the accuracy of these predictions. Motion analysis results showed that observed action cues alone primed both spatial incongruent and object congruent actions, consistent with the idea that the prime effect was driven by similarity between goals and kinematics. The observation of action and eye-gaze cues together induced a prime effect complementarily sensitive to object and spatial congruency. While observation of the agent's action kinematics triggered an object-centered and kinematic-centered action representation, independently, the complementary observation of eye-gaze triggered a more fine-grained representation illustrating a specification of action kinematics toward the selected goal. Even though both cues differentially contributed to action priming, their complementary integration led to a more refined pattern of action priming. [ABSTRACT FROM AUTHOR]

In the scientific literature, there is much evidence of a relationship between age and dexterity, where increased age is related to slower, less nimble and less smooth, less coordinated and less controlled performances. While some suggest that the relationship is a direct consequence of reduced muscle strength associated to increased age, there is a lack of research that has systematically investigated the relationships between age, strength and hand dexterity. Therefore, the aim of this study was to examine the associations between age, grip strength and dexterity. 107 adults (range 18-93 years) completed a series of hand dexterity tasks (i.e. steadiness, line tracking, aiming, and tapping) and a test of maximal grip strength. We performed three phases of analyses. Firstly, we evaluated the simple relationships between pairs of variables; replicating the existing literature; and found significant relationships of increased age and reduced strength; increased age and reduced dexterity, and; reduced strength and reduced dexterity. Secondly, we used standard Multiple Regression (MR) models to determine which of the age and strength factors accounted for the greater variance in dexterity. The results showed that both age and strength made significant contributions to the data variance, but that age explained more of the variance in steadiness and line tracking dexterity, whereas strength explained more of the variance in aiming and tapping dexterity. In a third phase of analysis, we used MR analyses to show an interaction between age and strength on steadiness hand dexterity. Simple Slopes post-hoc analyses showed that the interaction was explained by the middle to older aged adults showing a relationship between reduced strength and reduced hand steadiness, whereas younger aged adults showed no relationship between strength and steadiness hand dexterity. The results are discussed in terms of how age and grip strength predict different types of hand dexterity in adults. [ABSTRACT FROM AUTHOR]

The present functional magnetic resonance imaging ( fMRI) study investigates the neural correlates of reachability judgements. In a block design experiment, 14 healthy participants judged whether a visual target presented at different distances in a virtual environment display was reachable or not with the right hand. In two control tasks, they judged the colour or the relative position of the visual target according to flankers. Contrasting the activations registered in the reachability judgement task and in the control tasks, we found activations in the frontal structures, and in the bilateral inferior and superior parietal lobe, including the precuneus, and the bilateral cerebellum. This fronto-parietal network including the cerebellum overlaps with the brain network usually activated during actual motor production and motor imagery. In a following event-related design experiment, we contrasted brain activations when targets were rated as 'reachable' with those when they were rated as 'unreachable'. We found activations in the left premotor cortex, the bilateral frontal structures, and the left middle temporal gyrus. At a lower threshold, we also found activations in the left motor cortex, and in the bilateral cerebellum. Given that reaction time increased with target distance in reachable space, we performed a subsequent parametric analysis that revealed a related increase of activity in the fronto-parietal network including the cerebellum. Unreachable targets did not show similar activation, and particularly in regions associated to motor production and motor imagery. Taken together, these results suggest that dynamical motor representations used to determine what is reachable are also part of the perceptual process leading to the distinct representation of peripersonal and extrapersonal spaces. [ABSTRACT FROM AUTHOR]

Recombinant fusion proteins containing arthropod toxins have been developed as a new class of biopesticides. The recombinant fusion protein Hv1a/GNA, containing the spider venom toxin ω-ACTX-Hv1a linked to snowdrop lectin (GNA)was shown to reduce survival of the peach-potato aphid Myzus persicae when delivered in artificial diet, with survival <10% after 8 days exposure to fusion protein at 1 mg/ml. Although the fusion protein was rapidly degraded by proteases in the insect, Hv1a/GNA oral toxicity to M. persicae was significantly greater than GNA alone. A construct encoding the fusion protein, including the GNA leader sequence, under control of the constitutive CaMV 35S promoter was transformed into Arabidopsis; the resulting plants contained intact fusion protein in leaf tissues at an estimated level of 25.6 ± 4.1 ng/mg FW. Transgenic Arabidopsis expressing Hv1a/GNA induced up to 40% mortality of M. persicae after 7 days exposure in detached leaf bioassays, demonstrating that transgenic plants can deliver fusion proteins to aphids. Grain aphids (Sitobion avenae) were more susceptible than M. persicae to the Hv1a/GNA fusion protein in artificial diet bioassays (LC50 = 0.73 mg/ml after 2 days against LC50 =1.81 mg/ml for M. persicae), as they were not able to hydrolyze the fusion protein as readily as M. persicae. Expression of this fusion protein in suitable host plants for the grain aphid is likely to confer higher levels of resistance than that shown with the M. persicae/Arabidopsis model system. [ABSTRACT FROM AUTHOR]

Two colonies of Asian corn borer, Ostrinia furnacalis (Guenée), artificially selected from a Bt-susceptible colony (ACB-BtS) for resistance to Cry1Ab (ACB-AbR) and Cry1Ac (ACB-AcR) toxins, were used to analyze inheritance patterns of resistance to Cry1 toxins. ACB-AbR and ACB-AcR evolved significant levels of resistance, with resistance ratios (RR) of 39-fold and 78.8-fold to Cry1Ab and Cry1Ac, respectively. The susceptibility of ACB-AbR larvae to Cry1Ac and Cry1F toxins, which had not previously been exposed, were significantly reduced, being >113-fold and 48-fold, respectively. Similarly, susceptibility of ACB-AcR larvae to Cry1Ab and Cry1F were also significantly reduced (RR > nine-fold, RR > 18-fold, respectively), indicating cross-resistance among Cry1Ab, Cry1Ac, and Cry1F toxins. However, ACB-AbR and ACB-AcR larvae were equally susceptible to Cry1Ie as were ACB-BtS larvae, indicating no cross-resistance between Cry1Ie and Cry1Ab or Cry1Ac toxins; this may provide considerable benefits in preventing or delaying the evolution of resistance in ACB to Cry1Ab and Cry1Ac toxins. Backcrossing studies indicated that resistance to Cry1Ab toxin was polygenic in ACB-AbR, but monogenic in ACB-AcR, whilst resistance to Cry1Ac toxin was primarily monogenic in both ACB-AbR and ACB-AcR, but polygenic as resistance increased. [ABSTRACT FROM AUTHOR]

Development of resistance in target pests is a major threat to long-term use of transgenic crops expressing Bacillus thuringiensis (Bt) Cry toxins. To manage and/or delay the evolution of resistance in target insects through the implementation of effective strategies, it is essential to understand the basis of resistance. One of the most important mechanisms of insect resistance to Bt crops is the alteration of the interactions between Cry toxins and their receptors in the midgut. A Cry1Ac-selected strain of Asian corn borer (ACB), Ostrinia furnacalis, a key pest of maize in China, evolved three mutant alleles of a cadherin-like protein (OfCAD) (MPR-r1, MPR-r2 and MPR-r3), which mapped within the toxin-binding region (TBR). Each of the three mutant alleles possessed two or three amino acid substitutions in this region, especially Thr1457→Ser. In highly resistant larvae (ACB-Ac200), MPR-r2 had a 26-amino acid residue deletion in the TBR, which resulted in reduced binding of Cry1Ac compared to the MPR from the susceptible strain, suggesting that the number of amino acid deletions influences the level of resistance. Furthermore, downregulation of OfCAD gene (ofcad) transcription was observed in the Cry1Ac resistant strain, ACB-Ac24, suggesting that Cry1Ac resistance in ACB is associated with the downregulation of the transcript levels of the cadherin-like protein gene. The OfCAD identified from ACB exhibited a high degree of similarity to other members of the cadherin super-family in lepidopteran species. [ABSTRACT FROM AUTHOR]

A Cry1Ab-resistant population of Asian corn borer (ACB-AbR) exhibiting approximately 100 times greater resistance to activated Cry1Ab than a susceptible population ( Ostrinia furnacalis; ACB- BtS), was previously shown to exhibit high levels of cross-resistance to Cry1Ah (131-fold), but no cross-resistance to Cry1Ie. It was suggested that the proposed mechanism of resistance was due to the alteration of specific receptors for Cry toxins in the midgut brush border membrane. In the present study a proteomic-based approach was used to identify proteins from brush border membrane vesicles (isolated from both resistant and susceptible Ostrinia furnacalis larvae) interacting with biotinylated Cry1Ab, Cry1Ah, and Cry1Ie. 2D-Electrophoresis in combination with ligand blots were employed and putative protein identities obtained using MALDI-ToF/ToF mass spectrometry. The V-type proton ATPase catalytic subunit A and heat shock 70 kDa proteins were identified as interacting with the Cry toxins tested in the ACB-AbR and ACB- BtS larvae. The biotinylated Cry toxins showed markedly stronger interactions with proteins in the resistant compared to the susceptible larvae, suggesting an up-regulation of the V-type proton ATPase catalytic subunit A and heat shock 70 kDa proteins in the resistant (ACB-AbR) larvae. Interestingly, Cry1Ie interactions with the V-type proton ATPase catalytic subunit A in the ACB- BtS larvae appeared to be absent. [ABSTRACT FROM AUTHOR]

Studies using transcranial magnetic stimulation have demonstrated that action observation can modulate the activity of the corticospinal system. This has been attributed to the activity of an 'action observation network', whereby premotor cortex activity influences corticospinal excitability. Neuroimaging studies have demonstrated that the context in which participants observe actions (i.e. whether they simply attend to an action, or observe it with the intention to imitate) modulates action observation network activity. The study presented here examined whether the context in which actions were observed revealed similar modulatory effects on corticospinal excitability. Eight human participants observed a baseline stimulus (a fixation cross), observed actions in order to attend to them, or observed the same actions with the intention to imitate them. Whereas motor evoked potentials elicited from the first dorsal interosseus muscle of the hand were facilitated by attending to actions, observing the same actions in an imitative capacity led to no facilitation effect. Furthermore, no motor facilitation effects occurred in a control muscle. Electromyographic data collected when participants physically imitated the observed actions revealed that the activity of the first dorsal interosseus muscle increased significantly during action execution compared with rest. These data suggest that an inhibitory mechanism acts on the corticospinal system to prevent the immediate overt imitation of observed actions. These data provide novel insight into the properties of the human action observation network, demonstrating for the first time that observing actions with the intention to imitate them can modulate the effects of action observation on corticospinal excitability. [ABSTRACT FROM AUTHOR]

Previous studies demonstrate that observing the movements of others can interfere with concurrent movement execution. This interference effect is attributed to incongruence between the observed and executed movements. The study presented here examined different aspects of observed and executed movement congruency. Participants attempted to trace straight lines in the air using one of two movement tasks while observing an experimenter perform movements varied by their task and spatial congruency. The data revealed that kinematic aspects of the observed movements were incorporated into the observer's own movements. Observing the same kinematics led to interference or facilitation effects depending on whether the direction of the observed movement was congruent or incongruent with the movement the participant performed. These data suggest that low-level properties of observed movements can modulate participant performance. [ABSTRACT FROM PUBLISHER]

This study aimed to quantify the intra-and inter-instrument reliability of the Actiwatch 4 accelerometer (AW4) in a mechanical setting. Twenty seven AW4 were attached to an isokinetic dynamometer and subjected to angular acceleration for 30 min at 50 deg/sec representing moderate intensity (MPA condition) and 200 deg/sec representing vigorous intensity (VPA condition), with a repeat trial conducted. Reliability was assessed using coefficient of variation (CV), absolute percent error (APE), and intraclass correlation coefficients (ICC). Mean AW4 activity counts displayed acceptable reliability according to CV in both conditions (ConMPA: CVintra = 4.6%, APEintra = 6.6%, CVinter = 6.4%, APEinter = 5.2%; ConVPA: CVintra = 3.9%, APEintra = 5.6%, CVinter = 5.9%, APEinter = 4.7%). When counts were re-categorised into minutes of MPA and VPA, lower CV values were observed (ConMPA: CVintra = 3.2%, APEintra = 4.5%, CVinter = 4.3%, APEinter = 3.2%; ConVPA: CVintra = 0.0%, APEintra = 0.0%, CVinter = 0.0%, APEinter = 0.0%). When activity counts were re-categorised as minutes of MVPA, excellent reliability was observed (CVintra, APEintra, CVinter, and APEinter = 0.0%) in both conditions. Mean AW4 activity counts exhibit reliability statistics comparable to other accelerometers. Reliability is improved when activity counts are re-categorised as time spent in MPA and VPA, with greatest reliability obtained when counts are recategorised as time spent in MVPA. As MVPA is the subcomponent of physical activity most associated with health benefits it would appear that the AW4 is reliable for measuring time spent in this health enhancing intensity category, at least from testing in a mechanical laboratory setting. [ABSTRACT FROM AUTHOR]

Based on literature identifying movement imagery, observation, and execution to elicit similar areas of neural activity, research has demonstrated that movement imagery and observation successfully prime movement execution. To investigate whether movement and observation could prime ease of imaging from an external visual-imagery perspective, an internal visual-imagery perspective, and kinesthetic modality, 36 participants (M age = 20.58; SD = 3.11; 18 women and 18 men) completed an adapted version of the Movement Imagery Questionnaire-Revised under four modes of delivery (movement prime, external observation prime, internal observation prime, and image-only). The results revealed that ease of imaging was significantly greater during the movement and observation prime conditions compared to the image-only condition (p < .05). Specifically when priming external visual imagery and internal visual imagery, observation facilitated ease of imaging only when the perspective was congruent with the imagery perspective. The results support the use of movement and observation to facilitate ease of imaging, but highlight the importance of considering the visual perspective when using observation. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that the observation of action can modulate motor performance. This literature has focused on manipulating the observed goal of the action, rather than examining whether action observation effects could be elicited by changing observed kinematics alone. In the study presented here, observed reach trajectory kinematics unrelated to the goal of the action were manipulated in order to examine whether observed movement kinematics alone could influence the action of the observer. Participants observed an experimenter grasp a target object using either a normal or an exaggeratedly high reaching action (as though reaching over an invisible obstacle). When participants observed the experimenter perform actions with a high reach trajectory, their own movements took on aspects of the observed action, showing greater wrist height throughout their reaching trajectory than under conditions in which they observed normal reaching actions. The data are discussed in relation to previous findings which suggest that kinematic aspects of observed movements can prime action through kinematic or intention based matching processes. [ABSTRACT FROM AUTHOR]

Examines the effects of an elderly stereotype prime on reaching and grasping actions. Factual background on the psychological aspects of prime exposure on words associated with an elderly stereotype; Focus on the area affected by stereotype prime within the overall action sequence; Increase in the gaps between ballistic actions compared with the relative duration of actions.

We examined the relations between attention and action in a patient with Balint's syndrome following bilateral damage involving the parietal lobes. The first two experiments used prolonged stimulus exposures and showed that unlike normals, the patient GK made independent actions to bilateral stimuli, even when explicitly instructed to make coordinated reaches. In contrast, bimanual actions to a single stimulus were coordinated in time. Experiments 3 and 4 employed reduced stimulus exposures to produce visual extinction. We found comparable extinction effects in detection and action, along with improved bimanual movements when the stimuli were grouped by collinearity and surface contrast, plus better coordination with bilateral stimuli proximity. The results are discussed in relation to the common role of visual selection processes in perception and action. [ABSTRACT FROM AUTHOR]

We report two sets of data on object and action selection in a patient, ES, with an impaired ability to make task-based actions to objects. In simple action tasks, ES often made familiar actions to objects rather than the action appropriate to the task rule. We show that, despite having impaired selection of action, ES was able to select the target for action (based on salient perceptual differences). Relatively good object selection occurred even when the distractor had a stronger learned response than the target. In addition we show that distractors close to the path of action to a target can compete for, but are rejected from, selection along with any concurrently activated response. Suppression of an activated response improved performance, when the response would have been inappropriate to the task. [ABSTRACT FROM AUTHOR]

The author highlights scientific developments in psychology as reflected in publications in the "British Journal of Psychology" (BJP). Topics the author covered include the parameter of impact considered by authors when deciding where to submit their best work, some of the concerns regarding impact factor (IF) and details of empirical studies with an applied perspective that were featured in the journal.

Assesses the manual interferences responses of direct action from a neuropsychological evidence. Determination of interference responses by stimulus familiarity and by spatial relations of the hand to the object; Effects of effectors and spatial uncertainty on interference responses.

A major cause of yield loss in wheat worldwide is the fungal pathogen Zymoseptoria tritici, a hemibiotrophic fungus which causes Septoria leaf blotch, the most destructive wheat disease in Europe. Resistance in commercial wheat varieties is poor, however, a link between reduced nitrogen availability and increased Septoria tolerance has been observed. We have shown that Septoria load is not affected by nitrogen, whilst the fungus is in its first, symptomless stage of growth. This suggests that a link between nitrogen and Septoria is only present during the necrotrophic phase of Septoria infection. Quantitative real-time PCR data demonstrated that WRKYs, a superfamily of plant-specific transcription factors, are differentially expressed in response to both reduced nitrogen and Septoria. WRKY39 was downregulated over 30-fold in response to necrotrophic stage Septoria, whilst changes in the expression of WRKY68a during the late biotrophic phase were dependent on the concentration of nitrogen under which wheat is grown. WRKY68a may therefore mediate a link between nitrogen and Septoria. The potential remains to identify key regulators in the link between nitrogen and Septoria, and as such, elucidate molecular markers for wheat breeding, or targets for molecular-based breeding approaches. [ABSTRACT FROM AUTHOR]

The author's express their happiness on being offered to become members of the new editorial board of the British Journal of Psychology which was started in 1904. They inform that they start their term in January 2013 and hope to contribute to the continued success of the journal. They state that their aim is to combine innovative and established elements to further promote topicality, quality, and inter nationality of the research published in the BJP.

Evidence is accumulating that commonly used pesticides are linked to decline of pollinator populations; adverse effects of three neonicotinoids on bees have led to bans on their use across the European Union. Developing insecticides that pose negligible risks to beneficial organisms such as honeybees is desirable and timely. One strategy is to use recombinant fusion proteins containing neuroactive peptides/proteins linked to a 'carrier' protein that confers oral toxicity. Hv1a/GNA (Galanthus nivalis agglutinin), containing an insect-specific spider venom calcium channel blocker (ω-hexatoxin-Hv1a) linked to snowdrop lectin (GNA) as a 'carrier', is an effective oral biopesticide towards various insect pests. Effects of Hv1a/GNA towards a non-target species, Apis mellifera, were assessed through a thorough early-tier risk assessment. Following feeding, honeybees internalized Hv1a/GNA, which reached the brain within 1 h after exposure. However, survival was only slightly affected by ingestion (LD50 > 100 µg bee-1) or injection of fusion protein. Bees fed acute (100 µg bee-1) or chronic (0.35 mg ml-1) doses of Hv1a/GNA and trained in an olfactory learning task had similar rates of learning and memory to no-pesticide controls. Larvae were unaffected, being able to degrade Hv1a/GNA. These tests suggest that Hv1a/GNA is unlikely to cause detrimental effects on honeybees, indicating that atracotoxins targeting calcium channels are potential alternatives to conventional pesticides. [ABSTRACT FROM AUTHOR]

Focuses on the study of the role of dorsal visual stream in automatic obstacle avoidance in visually guided reaching. Tendency of people reaching between two objects to alter reach trajectory in response to changes in obstacle position; Failure of people with damage to the posterior parietal lobe to adjust to the reaching response according to the location of target objects; Influence of attention on action.