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Taking different types of addictive drugs such as methamphetamine, heroin, and mixed drugs causes brain functional Changes. Based on the prefrontal functional near-infrared spectroscopy, this study was designed with an experimental paradigm that included the induction of resting and drug addiction cravings. Hemoglobin concentrations of 30 drug users (10 on methamphetamine, 10 on heroin, and 10 on mixed type) were collected. For these three types of individuals, the convolutional neural networks (CNN) was designed to classify eight Brodmann areas and the entire prefrontal area, and the average accuracy of the three classifications on each functional area was obtained. As a result, the classification accuracy was lower on the left side than on the right in the dorsolateral prefrontal cortex (DLPFC) of the drug users, while it was higher on the left than on the right in the ventrolateral prefrontal cortex (VLPFC), frontopolar prefrontal cortex (FPC), and orbitofrontal cortex (OFC). Then the differences in eight functional areas between the three types of individuals were statistically analyzed, and results showed significant differences in the right VLPFC and right OFC.

Background. Drastic functional reorganization was observed in the ipsilateral primary motor cortex (M1) of a Paralympic long jumper with a unilateral below-knee amputation in our previous study. However, it remains unclear whether long-term para-sports are associated with ipsilateral M1 reorganization since only 1 athlete with amputation was investigated. Objective. This study aimed to investigate the relationship between the long-term para-sports and ipsilateral M1 reorganization after lower limb amputation. Methods. Lower limb rhythmic muscle contraction tasks with functional magnetic resonance imaging and T1-weighted structural imaging were performed in 30 lower limb amputees with different para-sports experiences in the chronic phase. Results. Brain activity in the ipsilateral primary motor and somatosensory areas (SM1) as well as the contralateral dorsolateral prefrontal cortex, SM1, and inferior temporal gyrus showed a positive correlation with the years of routine para-sports participation (sports years) during contraction of the amputated knee. Indeed, twelve of the 30 participants who exhibited significant ipsilateral M1 activation during amputated knee contraction had a relatively longer history of para-sports participation. No significant correlation was found in the structural analysis. Conclusions. Long-term para-sports could lead to extensive reorganization at the brain network level, not only bilateral M1 reorganization but also reorganization of the frontal lobe and visual pathways. These results suggest that the interaction of injury-induced and use-dependent cortical plasticity might bring about drastic reorganization in lower limb amputees.

The global spread of COVID-19 has disrupted the normality of people’s daily lives, leading the population to social distancing and isolation. The closure of green areas also affected the well-being of the individual during the COVID-19 pandemic. Viewing flowers is expected to have similar positive effects to viewing natural scenery. Therefore, this study investigates how white, red, and yellow flower colors affect individuals’ psychological and physiological well-being. The experiment was conducted in an office-like setting with 50 participants. Participants looked at each flower color for 3 min. Electroencephalograms (EEGs), heart rate variability, and skin conductivity were measured to evaluate physiological responses along with both the semantic differential questionnaire (SD) and the Profile of Mood States (POMS) to assess psychological responses. EEGs showed that the mean values of alpha relative power in the prefrontal lobe were significantly higher when viewing yellow and red flowers vs. white flowers. Furthermore, heart rate variability revealed that viewing yellow and red flowers increased parasympathetic nerve activity significantly. After viewing the yellow and red flowers, the average results for each subscale of the POMS questionnaire improved. The vigor (V) subscale and overall mood status values were significantly improved. The results of the SD method revealed that viewing yellow and red flowers resulted in a significantly higher sense of relaxation, cheerfulness, and comfort than viewing white flowers.

Diabetics are prone to postoperative cognitive dysfunction (POCD). The occurrence may be related to the damage of the prefrontal lobe. In this study, the prefrontal lobe was segmented based on an improved clustering algorithm in patients with diabetes, in order to evaluate the relationship between prefrontal lobe volume and COPD. In this study, a total of 48 diabetics who underwent selective noncardiac surgery were selected. Preoperative magnetic resonance imaging (MRI) images of the patients were segmented based on the improved clustering algorithm, and their prefrontal volume was measured. The correlation between the volume of the prefrontal lobe and Z -score or blood glucose was analyzed. Qualitative analysis shows that the gray matter, white matter, and cerebrospinal fluid based on the improved clustering algorithm were easy to distinguish. Quantitative evaluation results show that the proposed segmentation algorithm can obtain the optimal Jaccard coefficient and the least average segmentation time. There was a negative correlation between the volume of the prefrontal lobe and the Z -score. The cut-off value of prefrontal lobe volume for predicting POCD was

Changes in brain metabolism are a hallmark of alcohol use disorder (AUD). Determining how AUD changes the brain proteome is critical for understanding the effects of alcohol consumption on biochemical processes in the brain. We used data-independent acquisition mass spectrometry proteomics to study differences in the abundance of proteins associated with AUD in prefrontal lobe and motor cortex from autopsy brain. AUD had a substantial effect on the overall brain proteome exceeding the inherent differences between brain regions. Proteins associated with glycolysis, trafficking, the cytoskeleton, and excitotoxicity were altered in abundance in AUD. We observed extensive changes in the abundance of key metabolic enzymes, consistent with a switch from glucose to acetate utilization in the AUD brain. We propose that metabolic adaptations allowing efficient acetate utilization contribute to ethanol dependence in AUD.

The supplementary motor area (SMA) syndrome is a frequently encountered clinical phenomenon associated with surgery of the dorsomedial prefrontal lobe. The region has a known motor sequencing function and the dominant pre-SMA specifically is associated with more complex language functions; the SMA is furthermore incorporated in the negative motor network. The SMA has a rich interconnectivity with other cortical regions and subcortical structures using the frontal aslant tract (FAT) and the frontostriatal tract (FST). The development of the SMA syndrome is positively correlated with the extent of resection of the SMA region, especially its medial side. This may be due to interruption of the nearby callosal association fibres as the contralateral SMA has a particular important function in brain plasticity after SMA surgery. The syndrome is characterized by a profound decrease in interhemispheric connectivity of the motor network hubs. Clinical improvement is related to increasing connectivity between the contralateral SMA region and the ipsilateral motor hubs. Overall, most patients know a full recovery of the SMA syndrome, however a minority of patients might continue to suffer from mild motor and speech dysfunction. Rarely, no recovery of neurological function after SMA region resection is reported.

Background Bipolar disorder (BD) might be associated in disturbances in brain networks. However, little is known about the abnormalities in structural brain connectivity which might be related to vulnerability to BD and predictive of the emergence of manic symptoms. No previous study has investigated the effect of subthreshold syndromes on structural dysconnectivity in offspring of parents with BD (BDoff). Methods We investigated diffusion weighted images of 70 BDoff and 48 healthy controls (HC). Nineteen of the 70 BDoff had presented with subthreshold syndromes indicating a clinical high-risk (BDoff-CHR) and other 51 BDoff had no such history (BDoff-non-CHR). Global and regional network properties, rich club organization and inter-regional connectivity in BDoff and healthy controls were investigated using graph analytical methods and network-based-statistics (NBS). Results Global properties of WM networks appeared to be intact in BDoff-CHR and BDoff-non-CHR. However, decreased regional connectivity in right occipito-parietal areas and cerebellum was a common feature of both BDoff groups. Importantly, decreased interregional connectivity between nodes in right and left prefrontal regions, nodes in right prefrontal lobe and right temporal lobe and nodes in left occipital area and left cerebellum were evident in BDoff-CHR but not BDoff-non-CHR. Limitations The cross-sectional nature of the study was the main consideration. Conclusion Decreased regional connectivity in right posterior brain regions might be related to vulnerability to BD. On the other hand, interregional dysconnectivity in anterior frontal and limbic regions and left posterior brain regions might be evident in individuals genetically at risk for developing BD who had experienced subthreshold mood symptoms.

A 56-year-old woman presented with electroclinical focal seizures in the setting of hyperglycemia (808 mg/dL) and elevated HbA1c of 14.7%. She had varying seizure semiology, consisting of early forced head turn to the left, speech arrest, left facial twitching, and impaired awareness. Her seizures arose from the right frontotemporal area on EEG (figure 1). MRI showed hypointensities in the right prefrontal lobe that resolved after 6 months (figure 2).

Our aim was to identify the longitudinal changes in gray matter volume (GMV) and secondary alterations of structural covariance after pontine stroke (PS). Structural MRI and behavioral scores were obtained at 1 week, 1 month, 3 months, 6 months in 11 patients with PS. Twenty healthy subjects underwent the same examination only once. We used voxel-based morphometry and seed-based structural covariance to investigate the altered GMV and structural covariance patterns. Furthermore, the associations between the GMV changes and behavioral scores were assessed. With the progression of the disease, GMV decreased significantly in the bilateral cerebellar posterior lobe (ipsilateral Crus II (CBE Crus II_IL) and contralateral Crus I (CBE Crus I_CL)), which were initially detected at the first month and then continued to decrease during the following 6 months. Based on the CBE Crus II_IL and CBE Crus I_CL as seed regions, structural covariance analysis revealed that there were more positively and negatively correlated brain regions in PS group, mainly distributed in the bilateral prefrontal lobe, parietal lobe, temporal lobe, paralimbic system and cerebellum. In addition, PS group showed more additional correlations between these covariant brain regions, and the changes of GMV in these regions were correlated with behavioral scores related to motor and cognitive functions. These findings indicate that PS could lead to significant GMV atrophy in the bilateral cerebellar posterior lobe at the early stage, accompanied by anomalous structural covariance patterns with more covariant brain regions and additional structural connectivity, which may provide useful information for understanding the neurobiological mechanisms of behavioral recovery after PS.

Introduction The neural mechanism underlying decision‐making, which is an important component of executive function, is complex and not fully understood. Few studies have directly investigated the two types of decision‐making functions – under ambiguity and under risk – in patients with brain tumors in different brain regions. Methods Participants were classified into the ventral prefrontal cortex tumor group (VPFC, n = 27), the dorsolateral prefrontal cortex tumor group (DLPFC, n = 29), and matched healthy controls (HCs, n = 32). All participants were given a battery of neuropsychological tests, and they then performed the Iowa Gambling Task (IGT) and the Game of Dice Task (GDT) to assess their decision‐making under ambiguity and under risk, respectively. Results The two patient groups performed significantly worse on attention, memory, information processing, and executive function. Additionally, patients in the DLPFC group performed significantly worse on the memory and information processing tests compared with the VPFC and HC groups. Conclusion This study found that the decision‐making functions of participants in the VPFC and DLPFC tumor groups were impaired to varying degrees. Among them, there was decision‐making impairment under ambiguity and under risk in the VPFC group, and there was decision‐making impairment under risk in the DLPFC group., The neural mechanism underlying decision‐making is complicated and not fully understood. Patients with brain tumors may be a better research focus regarding decision‐making functions. Research showed that patients with prefrontal tumor showed deficits in other several cognitive and decision‐making tasks.

International audience; INTRODUCTION: Environmental dependency phenomena refer to the enslavement of patients' performances under the characteristics of the tasks and were first described in case of prefrontal lobe damage. Two forms of environmental dependency, executive and social, may be dissociated, which involve respectively dorsolateral and orbital prefrontal cortex (PFC) dysfunction. Schizophrenia is widely considered to be caused by PFC dysfunction, but no study to date has addressed environmental dependency in this pathology.METHODS: We compared patients (N = 17) and healthy controls (N = 28) on a task dedicated to the study of environmental dependency.RESULTS: Our results demonstrate the presence of environmental dependency in schizophrenia. Each form of environmental dependency can be highlighted independently, as previously demonstrated by studies with prefrontal patients.CONCLUSIONS: These findings suggest specific prefrontal dysfunction for each subgroup of patients and demonstrate a dissociation between socio-cognitive and neurocognitive performance in schizophrenia. Additionally, we found relationships between symptomatology and environmental dependency. This pilot study supports the relevance of studying environmental dependency to highlight specific patterns of prefrontal disorders in schizophrenia, which may contribute to a better understanding of PFC dysfunction in schizophrenia.

White matter fiber tracts demonstrate heterogeneous vulnerabilities to aging effects. Here, we estimated age-related differences in tract properties using UK Biobank diffusion magnetic resonance imaging data of 7167 47- to 76-year-old neurologically healthy people (3368 men and 3799 women). Tract properties in terms of generalized fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity were sampled on 76 fiber tracts; for each tract, age-related differences were estimated by fitting these indices against age in a linear model. This cross-sectional study demonstrated 4 age-difference patterns. The dominant pattern was lower generalized fractional anisotropy and higher axial diffusivity, radial diffusivity, and mean diffusivity with age, constituting 45 of 76 tracts, mostly involving the association, projection, and commissure fibers connecting the prefrontal lobe. The other 3 patterns constituted only 14 tracts, with atypical age differences in diffusion indices, and mainly involved parietal, occipital, and temporal cortices. By analyzing the large volume of diffusion magnetic resonance imaging data available from the UK Biobank, the study has provided a detailed description of heterogeneous age-related differences in tract properties over the whole brain which generally supports the myelodegeneration hypothesis.

We are conscious and verbally report some of the information reaching our senses, although a big amount of information is processed unconsciously. There is no agreement about the neural correlates of consciousness, with low-level theories proposing that neural processing on primary sensory brain regions is the most important neural correlate of consciousness, while high-level theories propose that activity within the fronto-parietal network is the key component of conscious processing (Block, 2009). Contrary to the proposal of high-level theories, patients with prefrontal lobe damage do not present clinical symptoms associated to consciousness deficits. In the present study, we explored the conscious perception of near-threshold stimuli in a group of patients with right prefrontal damage and a group of matched healthy controls. Results demonstrated that perceptual contrast to perceive the near-threshold targets was related to damage to the right dorsolateral prefrontal cortex, and with reduced integrity of the ventral branch of the right superior longitudinal fascicule (SLF III). These results suggest a causal role of the prefrontal lobe in conscious processing.

Whereas it was previously thought that there was a single overarching frontal lobe syndrome, it is now clear that several distinct cognitive and behavioral processes are mediated by the frontal lobes. This article reviews these processes and the underlying neuroanatomy and provides an approach to the assessment of prefrontal lobe functions at the bedside.Cognitive and behavioral frontal lobe functions are mediated by the prefrontal regions rather than the frontal lobes as a whole. At least five separate prefrontal functions have been defined: energization, task setting, monitoring, behavioral/emotional regulation, and metacognition. Energization is mediated by the superior medial prefrontal cortices bilaterally, task setting by the left lateral frontal cortex, monitoring by the right lateral prefrontal cortex, behavioral/emotional regulation by the orbitofrontal cortex, and metacognition by the frontal poles. Only task setting and monitoring are considered executive functions.Distinct cognitive and behavioral processes are mediated by different parts of the frontal lobe. Lesions in these areas result in characteristic clinical deficits that are discussed in this article. Key messages are that prefrontal regions mediate the higher cortical functions (as opposed to the frontal lobes in general) and that prefrontal functions are not equivalent to executive functions.

In this study we compared the neuropsychological profile of phenylketonuria (PKU) and human immunodeficiency virus (HIV) to examine the specificity of the executive function (EF) impairment reported in these two patologies. A total of 55 age-matched children and adolescents were assessed, including 11 patients with PKU, 16 patients with HIV and 28 healthy controls, underwent a neuropsychological assessment. Although neither the PKU nor the HIV group scored below the normative ranges, both groups showed lower scores in neuropsychological tests engaging EFs than controls. In addition, compared to patients with PKU the HIV group performed significantly worse in the Trail-Making Test A, Corsi Span and Verbal Fluency. These findings suggest that EF impairments in PKU (a) are limited to EFs (i.e., working memory and attentional shifting), (b) are not simply due to generalized processing speed deficits and (c) overlap partially with EF impairments found in a chronic medical developmental disorder.

International audience; The concepts of "frontal" and "dysexecutive" syndromes are still a matter of debate in the literature. These terms are often used interchangeably but can be distinguished when considering specific frontal behavioural deficits which occur during social interaction. Despite being of interest for the clinical assessment and care management of patients with anterior brain damage, few studies have tried to disentangle the specificity of each syndrome. We report the case of eight patients with frontal lobe damage who were assigned to one of two groups based on whether or not they showed a dysexecutive syndrome. The nondysexecutive group differed from the dysexecutive group in showing environmental dependency phenomena, behavioural disorders triggered by social interaction. By adopting an interactionist perspective, this pilot study contributes to defining more precisely the distinction between "frontal" and "dysexecutive" syndromes. The discussion focuses on the potential interest of the interactionist approach in designing appropriate methodologies of assessment and rehabilitation of patients with frontal lobe syndrome.

Source at https://doi.org/10.1016/j.neuroimage.2018.01.043. Creatine is a key regulator of brain energy homeostasis, and well-balanced creatine metabolism is central in healthy brain functioning. Still, the variability of brain creatine metabolism is largely unattended in magnetic resonance spectroscopy (MRS) research. In the human brain, marginal sex differences in creatine levels have been found in the prefrontal cortex. It is however not known to what degree these sex differences are stable or change with varying gonadal hormone levels. The current study therefore investigated creatine in the prefrontal cortex across the menstrual cycle. In addition, we explored cerebral asymmetries. Creatine, Choline (Cho), N-acetylaspartate (NAA), Myo inositol (mI), and glutamate þ glutamine (Glx) were assessed three times in 15 women and 14 men using MRS. Women were tested in cycle phases of varying hormone levels (menstrual, follicular, and luteal phase). Prefrontal creatine was found to change across the menstrual cycle, in a hemisphere-specific manner. Women in the follicular phase showed increased left prefrontal creatine accompanied with reduced right prefrontal creatine, while this asymmetry was not present in the luteal phase. In men, the creatine levels remained stable across three testing sessions. In general, both men and women were found to have higher creatine levels in the left as compared to the right prefrontal cortex. Exploratory analyses of other metabolites showed similar asymmetries in NAA, Cho, and mI, while Cho also showed a menstrual cycle effect. This is the first time that sex hormone-related changes in creatine metabolism have been demonstrated in the human brain. These findings may have important methodological implications for MRS research, as it supports previous concerns against uncritical usage of creatine as a reference measure for other metabolites, assumed to be invariant across individuals and conditions.

Background. The prospective memory (PM) construct is aimed at capturing cognitive operations involved in the successful accomplishment of delayed intentions. It is generally agreed that PM impairment occurs in patients with prefrontal lobes damage.Objective. To evaluate if there is a causal role of a deficit of executive abilities (failures of planning, set-shifting, selective attention, or working memory) over the PM impairment.Methods. We report a detailed investigation of PM and executive abilities in two patients with posttraumatic damage to prefrontal lobes who complained from a reduced compliance with appointments and daily routines.Results. Laboratory tests confirmed a difficulty in fulfilling delayed intentions in response to the occurrence of critical events and elapsed time. In one patient, PM impairment was associated with poor performance on tests investigating planning, working memory, and mental shifting. The other patient performed in the normal range on all executive tests.Conclusions. Despite the frequent claim of a dependence of PM deficits from executive dysfunction, the reported cases demonstrate that this is not necessarily the case. The results are discussed in the light of current hypotheses relating PM impairment to other deficits that commonly occur as a result of damage to the prefrontal lobes.

The intelligence quotient (IQ) is typically associated with the architecture of gray and white matter in specific brain regions, and this association appears to be genetically based. However, specific sources of genetic variation for the association have not been studied extensively. Using diffusion tensor imaging in 15 mental retardation patients and 80 healthy volunteers, we studied the association between white matter architecture and IQ and also investigated the effects of COMT val158met on this association. The results showed that fractional anisotropy (FA) values in the prefrontal lobe and the hippocampus formation were associated with IQ and that val158met may affect this association. Subjects who were val homozygous showed steeper slopes for regression of the FA value on IQ than met carriers. Our findings suggest that COMT val158met may contribute to intelligence by affecting the association between IQ and the white matter architecture in the prefrontal lobe and the hippocampal formation.

Chronic alcohol abuse leads to morphological changes of the brain. We investigated if these volumetric changes are reversible after a period of abstinence. For this reason 41 male and 15 female alcohol patients underwent MRI-scanning after in-patient detoxification (baseline) entering alcoholism treatment programs, and between 6 and 9 months later (follow-up), in a phase of convalescence. Additionally, 29 male and 16 female control subjects were examined. The MRI-scans were delineated and the resulting regions of interest, volumes of lateral ventricles and prefrontal lobes were expressed relatively to total brain volume. Compared to control subjects alcohol patients showed bilaterally decreased prefrontal lobes (11% reduction) and increased lateral ventricles (up to 42% enlargement). The extent of the ventricular increase was depending on patient’s additional psychiatric diagnosis, showing smaller lateral ventricles in patients with additional personality disorder. While at follow-up the size of prefrontal lobes remained unchanged, volumes of the lateral ventricles decreased (5–6% reduction) in alcohol patients with abstinence and improved drinking behavior, especially in patients that underwent only one detoxification. The extent of the ventricular enlargement correlated with the elevation of alcohol related laboratory measures (mean corpuscular volume, gamma-glutamyl transpeptidase). In conclusion this study confirms the hypothesis that alcoholism causes brain damages that are partially reversible. It should be analyzed in further studies with larger sample sizes, if complete brain regeneration is possible maintaining abstinence over a longer period.

The Rey-Osterrieth Complex Figure Test (ROCF), which was developed by Rey in 1941 and standardized by Osterrieth in 1944, is a widely used neuropsychological test for the evaluation of visuospatial constructional ability and visual memory. Recently, the ROCF has been a useful tool for measuring executive function that is mediated by the prefrontal lobe. The ROCF consists of three test conditions: Copy, Immediate Recall and Delayed Recall. At the first step, subjects are given the ROCF stimulus card, and then asked to draw the same figure. Subsequently, they are instructed to draw what they remembered. Then, after a delay of 30 min, they are required to draw the same figure once again. The anticipated results vary according to the scoring system used, but commonly include scores related to location, accuracy and organization. Each condition of the ROCF takes 10 min to complete and the overall time of completion is about 30 min.

Non-invasive measures of brain gamma-aminobutyric acid (GABA) concentrations may be especially useful in the identification of cocaine-related changes in brain chemistry that can be used to guide the development of future treatments for cocaine-dependent persons. This study assessed whether brain GABA levels in cocaine-dependent subjects with and without an alcohol disorder differ from GABA levels in healthy comparison subjects. Two-dimensional, proton magnetic resonance spectroscopy was used to determine GABA levels in the left prefrontal lobe of cocaine-dependent subjects (N=35) recruited from a National Institute on Drug Abuse (NIDA)-sponsored treatment trial of cocaine dependence and a comparison group (N=20). At treatment baseline, mean GABA concentrations were 0.93+/-0.27 mM/kg in cocaine-dependent subjects and 1.32+/-0.44 mM/kg in the comparison sample (t [d.f.=53]=3.65, P0.001). Cocaine-dependent subjects with a history of a co-morbid alcohol disorder (N=23) had significantly lower baseline GABA levels (0.87 mM/kg) (t [d.f.=41]=4.31, P0.001) than the comparison group. However, cocaine-dependent subjects without an alcohol disorder (N=12) also had lower GABA levels (1.04 mM/kg) than the comparison subjects (t [d.f.=30]=2.09, P=0.045), suggesting that cocaine dependence alone can decrease GABA levels.

Both simple attention tasks (e.g. letter cancellation) and most tasks of higher cognitive processing (e.g. word generation) are known to activate the dorsolateral prefrontal cortex (PFC). While attention and higher cognitive processing differ phenomenologically, with attention tasks requiring great subjective effort despite their simplicity, possible physiological differences in the activation of the PFC between the two types of cognitive processing have remained uninvestigated. Hemodynamic changes in the PFC during activation due to tasks of attention and those of higher cognitive processing were examined using near-infrared spectroscopy in 10 Japanese and 10 American healthy adults. In tasks of higher cognitive processing, which included both verbal and non-verbal tasks, the concentration of oxygenated hemoglobin ([HbO2]) increased, and that of deoxygenated hemoglobin ([HbR]) decreased, with an increase in the tissue hemoglobin saturation (THS). In tasks of attention, which consisted of the letter cancellation and continuous performance test, both [HbO2] and [HbR] increased, with no significant changes in the THS observed. The distinctive patterns of hemodynamic changes were not affected by the factors of task difficulty or language. The change in [HbR] may be a physiological marker of the prefrontal lobe activation that discriminates between attention and higher cognitive processing. The increase in [HbR] suggests increased oxygen consumption of the PFC during tasks of attention, which might be related to the disproportionately great subjective effort associated with sustained attention. The physiological alteration in hemodynamic patterns according to changes in cognition needs to be examined in subjects with prefrontal lobe dysfunction, such as schizophrenia and mood disorder.

Relatively little is known about normal prefrontal lobe development. We used three-dimensional magnetic resonance imaging (MRI)-based brain volumetry to characterize developmental changes in prefrontal lobe volumes in infants and children. Prefrontal volumes were determined in 30 subjects aged 5 months to 18 years (221 months) and 3 adults aged 28-39 years (324-468 months). Images were acquired on a 1.5-T MRI system using T1-weighted gradient-echo sequences. Volumes of the frontal and prefrontal lobes were determined using a workstation, and the prefrontal-to-frontal volume ratio was calculated. Prefrontal lobe volume increased slowly until 8 years (96 months) of age, contrasting sharply with rapid growth between 8 and 14 years (96 and 168 months). The prefrontal-to-frontal volume ratio increased with age as a sigmoid growth curve. A prefrontal growth spurt occurs in late childhood. Knowledge of prefrontal lobe development is essential for understanding cognitive development and dysfunction.

International audience; Objective. Human decision-making is a growing area of research most commonly associated with the Iowa Gambling Task (IGT), which was first developed to assess patients with prefrontal cortex (PFC) damage. The IGT is now considered an appropriate task to predict behavioral disorders in various clinical populations. However, several studies have questioned the validity and reliability of the task, arguing that its particular payoff scheme may influence the decision-making process in terms of sensitivity to gain-loss frequency (GLF) rather than long-term outcome (the basic assumption of IGT). Despite the potential significance of this assertion for the diagnosis of decision-making deficits, few studies have addressed the influence of GLF on IGT performances in clinical populations, and there is no study to date that involves patients with prefrontal lobe damage. Method. We tested 17 patients with PFC damage and 17 matched healthy controls with the IGT to analyze influence in choice behavior of both long-term outcomes and GLF. Results. There was a difference between groups in the GLF score, but none between groups in the long-term outcome variable (the traditional measure). Our findings demonstrate that only control subjects seemed able to consider both long-term outcome and GLF. Conclusions. The discussion focuses on the contribution of empirical data, which may have implications for the clinical assessment of decision-making ability with the IGT.

In 11 healthy volunteers, we used event-related potentials (ERP) to investigate the frontal activity associated with imagining a beat. In imagery sessions, subjects were asked to imagine a rhythm during a silent recording period following a series of guide sounds played at 1 Hz. In control sessions, subjects were asked to imagine a vowel sound (“a”) continuously during the silent recording period. In eight subjects, relative negative potentials were recorded during imagery sessions (compared with potentials in control sessions), with timing that was similar to that of the guide sounds. Activity in the left frontal region was more significant than that in other areas during beat imagination. These data indicate that a semantic strategy for simple rhythm imagery might involve temporary phasic activation in the left frontal area, although rhythm production and perception might be generated in the right side, as reported in previous studies.

The present study examined influences of reading aloud and performing simple calculation on the cognitive functioning of healthy elderly adults, based on the findings that these tasks activated the prefrontal lobe. The elderly adults' memory and inhibitory functions were assesed by Short-Term memory, CST, Stroop, and SRC tasks, before and after intervention for 18 months. The study found that the learning group had significant improvement from the pre- to the post-test for the short-term memory, STM, CST, and Stroop tasks. On the other hand, there was significant decline over the 18 months in the control group which was given only the assessment tasks. These results are discussed in terms of the effectiveness of cognitive training.

PURPOSE OF THE REPORT The aim of this study is to observe the abnormalities of regional cerebral blood flow (rCBF) in migraine patients and to evaluate its relation to the severity of the headache in patients with migraine. PATIENTS AND METHODS The rCBF imaging was done on 19 patients with migraine and 15 normal controls using single-photon emission computed tomography (SPECT). The abnormal character of cerebral perfusion function was analyzed with Statistical Parametric Mapping (SPM) software, and the headache grade of patients was evaluated with the headache severity measuring scale. RESULTS The results of SPM analysis demonstrated a decreased rCBF on both sides of the frontal and temporal lobes, left parietal lobe, and right occipital lobe (P < 0.001), and increased rCBF focus on the left prefrontal lobe and right temporal lobe (P < 0.001). The headache scores in migraineurs were correlated to the rCBF on the bilateral temporal lobes and right frontal lobe (P < 0.001). CONCLUSIONS The migraineurs had lower rCBF at the frontal and temporal lobes, and the lower rCBF was correlated to the degree of headache.

OBJECTIVE It is unclear whether atlas-based parcellation is suitable in aging cohorts because age-related brain changes confound the performance of automatic methods. We assessed atlas-based parcellation of the prefrontal lobe in an aging population using visual assessment and volumetric and spatial concordance. METHODS We used an atlas-based approach to parcellate brain MR images of 90 non-demented healthy adults, aged 72.7 ± 0.7 years, and assessed performance. RESULTS Volumetric assessment showed that both single-atlas- and multi-atlas-based methods performed acceptably (intraclass correlation coefficient [ICC], 0.74-0.76). Spatial overlap measurements showed that multi-atlas (dice coefficient [DC], 0.84) offered an improvement over the single-atlas (DC, 0.75-0.78) approach. Visual assessment also showed that multi-atlas outperformed single atlas and identified an additional postprocessing step of cerebrospinal fluid removal, enhancing concordance (intraclass correlation coefficient, 0.86; DC, 0.89). CONCLUSIONS Atlas-based parcellation performed reasonably well in the aging population. Rigorous performance assessment aided method refinement and emphasizes the importance of age matching and postprocessing. Further work is required in more varied subjects.

The prefrontal cortex plays an especially important role in human social-cognitive behavior. It has been difficult to quantify deficits in this domain in patients with frontal lobe lesions using standardized psychological instruments. We administered the Everyday Problem Solving Inventory (EPSI), which is composed of a range of scenarios depicting everyday social problems and their possible solutions, to a group of patients with frontal lobe lesions who were required to rate each of 4 possible solutions to each problem for their effectiveness. Our sample consisted of 27 normal controls (NCs), 33 patients with focal frontal lobe lesions (FLL), and 3 patients with frontal lobe dementia (FLD). The performance of the FLL patients on the EPSI instrument was also compared with their performance on traditional neuropsychological tests. The results indicated that the FLD patients' EPSI rank ordering of social problem solutions was uncorrelated with the performance of NCs and about half of the FLL patients EPSI rank orderings of solutions also varied substantially from those of the NCs. These same FLL patients also had the lowest scores, compared to FLL patients whose judgements on the EPSI were similar to that of the NCs, on a set of neuropsychological tasks sensitive to frontal lobe dysfunction. There was no obvious relationship between locus of lesion within the frontal lobes and performance on the EPSI. These results suggest that some patients with prefrontal lobe lesions may have impaired social judgement that can be directly revealed through the use of a conventional psychological inventory such as the EPSI.

Purpose:To understand the role of O2 utilization in the sex differences of fatigue during intermittent activity, we compared the cerebral (prefrontal lobe) and muscle (vastus lateralis) oxygenation of men and women during repeated-sprint exercise (RSE).Methods:Ten men and 10 women matched for initial-sprint mechanical work performed ten, 10 s cycle sprints (with 30 s of rest) under normoxic (NM: 21% FIO2) and acute hypoxic (HY: 13% FIO2) conditions in a randomized single-blind and crossover design. Mechanical work was calculated and arterial O2 saturation (SpO2) was estimated via pulse oximetry during every sprint. Cerebral and muscle oxy- (O2Hb) and deoxy-hemoglobin (HHb) were monitored continuously by near-infrared spectroscopy.Results:Compared with NM, work decrement was accentuated (P = 0.01) in HY for both men (–16.4 ± 10.3%) and women (–16.8 ± 9.0%). This was associated with lower SpO2 and lower cerebral Δ[O2Hb] in both sexes (–13.6 ± 7.5%, P = .008, and –134.5 ± 73.8%, P = .003, respectively). These HY-induced changes were nearly identical in these men and women matched for initial-sprint work. Muscle Δ[HHb] increased 9-fold (P = .009) and 5-fold (P = .02) in men and women, respectively, and plateaued. This muscle deoxygenation was not exacerbated in HY.Conclusions:Results indicate that men and women matched for initial-sprint work experience similar levels of fatigue and systemic, cerebral, and peripheral adjustments during RSE performed in NM and HY. These data suggest that cerebral deoxygenation imposes a limitation to repeated-sprint performance.

We describe a 2-DE proteomic reference map containing 227 basic proteins in the dorsolateral prefrontal cortex region of the human brain. Proteins were separated in the first dimension on pH 6-11 IPG strips using paper-bridge loading and on 12% SDS-PAGE in the second dimension. Proteins were subsequently identified by MS and spectra were analyzed using an in-house proteomics data analysis platform, Proline. The 2-DE reference map is available via the UCD 2-DE Proteome Database (http://proteomics-portal.ucd.ie:8082) and can also be accessed via the WORLD-2DPAGE Portal (http://www.expasy.ch/world-2dpage/). The associated protein identification data have been submitted to the PRIDE database (accession numbers 10018-10033). Separation of proteins in the basic region resolves more membrane associated proteins relevant to the synaptic pathology central to many neurological disorders. The 2-DE reference map will aid with further characterisation of neurological disorders such as bipolar and schizophrenia.

The aim of this study was to investigate the changes in regional cerebral blood flow (rCBF) with age in patients with attention deficit hyperactivity disorder (ADHD). Twenty-nine drug-naive ADHD subjects (24 boys, 5 girls; age 7–13; mean±SD=age 9.2±2.1) and 12 subjects with epilepsy (all diagnosed as having complex partial seizure, 6 boys, 6 girls; age 7–14; mean±SD=8.5±2.1) were included in the study. All cases of ADHD were diagnosed according to DSM-IV criteria. Cerebral blood flow was evaluated with Tc-99m-hexamethylpropyleneamine oxime (Tc99m HMPAO) brain single photon emission tomography (SPECT) during standard resting condition in all of the cases. Asymmetry indices for each region of interest were calculated. Absolute rCBF values were normalized as the absolute rCBF values divided by the whole brain absolute value. The prefrontal lobe asymmetry indices were significantly negatively correlated with age in ADHD cases ( r =−0.408, P =0.025), which indicated the increased prefrontal rCBF lateralization from the right to the left side with age. When ADHD cases older than 7 years of age were compared with those with epilepsy, the ADHD cases had lower right prefrontal and frontal rCBF and higher left parietal rCBF. The epilepsy group showed no significant correlations between age and asymmetry indices and showed a different developmental trajectory for prefrontal asymmetry and right prefrontal rCBF values. The results indicated that the left hemisphere dominance in the prefrontal cortex significantly increases with age in ADHD cases.

It has been previously proposed that conscious process involves the collapse of quantum, dynamical brain states through conscious observation. It has been further proposed that the brain process has an active role in selecting the status of uncertain stimuli. On the basis of these proposals it was predicted that event-related potentials (ERPs) would differ under unobserved versus pre-observed conditions. This has been found to be the case. Here we describe our most recent data, which shows that the difference between the pre-observed (inactive) and unobserved (active) conditions in ERPs is replicable, and seems to involve a selective process of matching stimulus and virtual brain state under the two conditions. Maximization of entropy by congruence of stimulus and brain potential through a quantum entropy operator is the proposed physical mechanism for this finding. The prefrontal lobe inhibition of perseverative brain states under the active condition is proposed to be the neurological mechanism of the findings.

The purpose of our study was to examine the neuroanatomical correlates of late-onset minor and major depression and to compare them with similar measures obtained from nondepressed controls. Our study groups were comprised of 18 patients with late-onset minor depression, 35 patients diagnosed with late-onset major depression, and 30 nondepressed controls. All subjects were scanned by using a 1.5-tesla MRI scanner. Absolute whole brain volume and normalized measures of prefrontal and temporal lobe volumes were obtained and used for comparison among groups. Our findings indicate that patients with minor depression present with specific neuroanatomical abnormalities that are comparable with the major depression group but significantly different from the controls. Normalized prefrontal lobe volumes show a significant linear trend with severity of depression, with volumes decreasing with illness severity. Whole brain volumes did not differ significantly among groups. These findings have broad implications for the biology of late-life depression and suggest that there may be common neurobiological substrates that underlie all clinically significant forms of late-onset mood disturbances.

The authors investigate: (1) whether there is a lateral effect of hydrogen (1H) magnetic resonance (MR) spectroscopy observable metabolite ratios between the right and the left prefrontal lobe in chronic schizophrenia; (2) whether there is a change of proton metabolite ratios in chronic schizophrenia after neuroleptic treatment; (3) whether there is a relation between changes in 1H MR spectra and the clinical assessment of Brief Psychiatric Rating Scale (BPRS); and (4) to investigate a hypofrontality hypothesis in schizophrenia in terms of neurochemical aspects.Localized in vivo 1H MR spectroscopy was used to measure the metabolite levels in the prefrontal lobes of control persons (n = 20) and of chronic patients before and after neuroleptic treatment (n = 34). The MR spectra of 8 cm3 voxels were compared with clinical assessment of BPRS in each subject.No significant metabolic lateral effect was established in both schizophrenia and control groups (P0.05). After neuroleptic treatment, chronic schizophrenic patients generally demonstrated a decrease of the complex of gamma-aminobutyric acid (GABA) and glutamate (Glu) containing (GABA + Glu)/creatine (Cr) ratio.The current follow-up 1H MR spectroscopy study shows a significant correlation between alterations of (GABA + Glu)/Cr ratio and BPRS, and supports a hypofrontality hypothesis in chronic schizophrenia. The reduction of (GABA + Glu)/Cr ratio after neuroleptic treatment may implicate the recovery of normal neuronal function in neurotransmitters. In vivo 1H MR spectroscopy may be a useful modality in follow-up evaluation of neuroleptic treatment in chronic schizophrenia.

The classical cytoarchitectonic maps of human prefrontal areas produced by various cartographers in the early part of this century, though similar in gross topography, differ from one another in their descriptions of the size, shape, and precise location of specific regions within the frontal promontory. The current advances in human neurobiology stimulated us to reinvestigate the cytoarchitecture of the human prefrontal cortex, beginning with areas 9 and 46, to establish a set of objective cytometric criteria for identification of these areas. Nisslstained and Gallyas-stained celloidin-embedded sections were prepared from the left hemispheres of 17 human subjects 23-73 years old, without history of neurological disease. In eight cases, light microscopic observations were supplemented by morphometric data collected on a research microscope equipped with differential interference contrast optics and interfaced to a TV monitor with video mixing equipment and a microcomputer. We used the three-dimensional counting method of Williams and Rakic (1988) to measure (1) total cortical and relative laminar thickness, (2) neuronal packing density per 0.001 mm3 in individual cortical layers, and (3) sizes of neuronal somata in selected cortical layers. Light microscopic analysis confirmed that the cortical layers are more differentiated in area 46 than in area 9, particularly at the borders of layer IV. Layers III and V exhibit clearer sublamination in area 9, while layer IV is also somewhat wider in area 46 than in area 9 (9.3% vs 6.4% of cortical thickness); the overall thickness of the cortex is the same in both areas. Cytometric analysis revealed that layer IV neurons of area 46 are more densely packed than those in area 9 (55.38 +/- 7.26 vs 45.80 +/- 4.45 neurons/0.001 mm3), as are neurons in the supragranular layers II and III combined (53.51 +/ 6.33 vs 45.69 +/ 3.81 neurons/0.001 mm3). Finally, neurons in area 46 are more homogeneous in size than those in area 9. Differences in myeloarchitecture are also evident: each area contains numerous, well-stained radial striae and two pronounced bands of horizontal fibers, but in general, area 46 is less myelinated than area 9. Objective cytometric methods can clearly distinguish two adjacent areas within the human prefrontal lobe. These findings may prove useful in the areal parcellation of the human cerebral cortex as well as provide a baseline for analysis of pathological changes in neurological and psychiatric disorders such as a schizophrenia, Huntington's or Alzheimer's diseases.

I have struggled with schizophrenia throughout my life. I present the case report of my life to demonstrate that the fundamental psychopathology that caused various symptoms of schizophrenia in me was that my prefrontal lobe had become inert and inactive. Once I reactivated my prefrontal lobe by various prefrontal lobe mediated cognitive exercises, my symptoms of schizophrenia resolved. On the basis of this case report, I hypothesize that the basic psychopathological disturbance in the patients of schizophrenia is that their prefrontal lobe becomes inert and inactive and reactivating that inert and inactive prefrontal lobe by various cognitive exercises may control their symptoms.

A PF-SN projection in the human cerebral neocortex was studied and the following results obtained. The PF-SN projection tract originates mainly from areas 9 and 10 and probably also from areas 46 and 47, and passes through the ipsilateral frontopontine tract. The main projecting area is the intermedial region of the pars compacta in the SN in a medio-lateral direction. The PF-SN projection fibers exist in quantities, possibly equal to those of the striatum-SN projection fibers. Fibers projecting from areas of the cerebral neocortex other than the PF to the pars compacta in the SN are likely to be absent.

1. 1. Electric stimulation of the uncus, cingulate, orbital and superior surface areas of the prefrontal cortex has been carried out in conscious man with special reference to its effect on respiration, state of consciousness and seizures. 2. 2. Studies were made on 24 patients while undergoing selective cortical undercutting in various areas of the frontal lobes for mental disease. 3. 3. Meager changes were noted following stimulation with high voltage and long duration of the cingulate, orbital and superior surface areas of the prefrontal lobes. In one case, stimulation of the cingulate surface produced a marked quieting effect on an agitated patient. 4. 4. Profound changes in respiration, state of consciousness and delayed appearance of seizures followed stimulation of the uncus with relatively low voltage and short duration. 5. 5. The uncal effects appear to be cumulative and when once initiated may continue for variable periods of time.

A series of 18 consecutive patients were selected for frontal lobe surgery over a 10 year period to obtain relief from chronic, intractable anxiety. Of the 13 who were not psychotic, 12 have returned to a well adjusted, independent existence at home without further hospitalization or continuation of therapy. Certain observations based on these case studies have been made, with full realization that generalizations cannot be drawn from 18 cases and that whatever value this study may have is dependent upon intense personal investigation of all relevant factors in a small group of individuals.

Introduction The right prefrontal lobe has not traditionally been considered eloquent brain. Resection of tumours within this region does not typically lead to permanent functional impairment. In this report, we highlight the case of a patient who developed autobiographical memory loss following an uncomplicated resection of a right prefrontal tumour. Case material A previously fit and well 15-year old presented with a persistent right-sided headache. An MRI demonstrated an expanded right mid-frontal gyrus with changes consistent with a low-grade tumour. The patient underwent a right-sided craniotomy and resection of the lesion which was confirmed as a WHO grade II diffuse astrocytoma. Postoperatively, the patient reported profound retrograde amnesia for a range of memory components, in particular autobiographical memory and semantic memory. Postoperative imaging showed a good resection margin with no evidence of underlying brain injury. Over an 18-month period, the patient showed no improvement in autobiographical memory; however, significant relearning of semantic knowledge took place and her academic performance was found to be in line with expectations for her age. Conclusion In this report, we discuss a case and review the literature on the role of the right prefrontal cortex in memory and caution on the perception of right prefrontal non-eloquence.