Anterior Cortical Areas Research Articles

Fine-grained features characterize hippocampal and amygdaloid change pattern in Parkinson's disease and discriminate cognitive-deficit subtype.

To extract vertex-wise features of the hippocampus and amygdala in Parkinson's disease (PD) with mild cognitive impairment (MCI) and normal cognition (NC) and further evaluate their discriminatory efficacy. High-resolution 3D-T1 data were collected from 68 PD-MCI, 211 PD-NC, and 100 matched healthy controls (HC). Surface geometric features were captured using surface conformal representation, and surfaces were registered to a common template using fluid registration. The statistical tests were performed to detect differences between groups. The disease-discriminatory ability of features was also tested in the ensemble classifiers. The amygdala, not the hippocampus, showed significant overall differences among the groups. Compared with PD-NC, the right amygdala in MCI patients showed expansion (anterior cortical, anterior amygdaloid, and accessory basal areas) and atrophy (basolateral ventromedial area) subregions. There was notable atrophy in the right CA1 and hippocampal subiculum of PD-MCI. The accuracy of classifiers with multivariate morphometry statistics as features exceeded 85%. PD-MCI is associated with multiscale morphological changes in the amygdala, as well as subtle atrophy in the hippocampus. These novel metrics demonstrated the potential to serve as biomarkers for PD-MCI diagnosis. Overall, these findings from this study help understand the role of subcortical structures in the neuropathological mechanisms of PD cognitive impairment.

Motor organization of unilateral polymicrogyria associated with ipsilateral brainstem atrophy – a case report

BackgroundPolymicrogyria refers to the disruption of normal cerebral cortical development late in neuronal migration or in early cortical organization. Although patients with polymicrogyria feature relatively favorable motor outcomes, polymicrogyric lesions accompanied by extensive unilateral hemispheric atrophy and ipsilateral brainstem atrophy may induce poorer motor outcomes. This study is the first to employ transcranial magnetic stimulation (TMS) and diffusion tensor imaging (DTI) to characterize changes to motor organization and white matter tracts induced by polymicrogyria.Case presentationWe document a case of a 16-year-old female with left hemiplegic unilateral polymicrogyria associated with ipsilateral brainstem atrophy. Magnetic resonance imaging (MRI) of the brain revealed unilateral polymicrogyria to have affected anterior cortical areas, including the perisylvian region on the right side. The right halves of the brain and brainstem were significantly smaller than the left halves. Although our patient was found to exhibit cortical dysplasia of the right frontoparietal and sylvian fissure areas and a decreased number of fibers in the corticospinal tract (CST) of the affected side on DTI, the connectivity of the CST was preserved up to the motor cortex. We also measured the cross-sectional area of the CST at the level of the pons. In TMS, contralateral motor evoked potentials (MEPs) were evoked from both hands, but the ipsilateral MEPs were evoked only from the left hand. The left hand featured a long duration, polyphasic pattern of contralateral MEPs.Discussion and conclusionTMS revealed that the concurrent bilateral projections to the paretic hand from the affected and unaffected hemispheres and contralateral MEPs in the paretic hand were polyphasic, indicating delayed electrophysiological maturation or a pathologic condition of the corticospinal motor pathways. In DTI, the cross-sectional area of the CST at the level of the pons on the affected side was smaller than that on the unaffected side. These DTI findings reveal an inadequate CST volume. Despite extensive brain malformation and ipsilateral brainstem atrophy, our patient had less severe motor dysfunction and presented with involuntary mirror movements. Mirror movements in the paretic hand are considered to indicate ipsilateral corticospinal projections from the unaffected hemisphere and may suggest favorable motor outcomes in early brain injury.

Церебральный энергообмен у работников ядерно опасных предприятий и производств с низким уровнем психофизиологической адаптации

Psychophysiological assessment of employees of 10 Russian nuclear power plants revealed a low degree of psychophysiological adaptation (PPA) in 30% of subjects. Studying the fuctional activity (FA) of the brain by EEG revealed the decline in FA in individuals with the low degree of PPA. The impaired cerebral energy exchange could be one of the factors contributing to the decline in the brain functional state. The study was aimed to assess the features of the cerebral energy exchange in the employees of the hazardous nuclear facilities and productions with the low degree of PPA. A total of 159 EEG recordings acquired from individuals with the low degree of PPA (50.8 ± 4.6), and 152 EEG recordings acquired from individuals with the high degree of PPA (48.8 ± 1.5) were studied. Energy exchange was assessed in individuals with the low FA of both brain as a whole and the following conditionally distinguished structural and functional units (SFUs) of the CNS: mainly cerebral cortex (SFU-1), cortical-subcortical interactions (SFU-2), central control of the cardiovascular system (SFU-3). EEG was recorded by standard method using the electroencephalography unit. The magnitude of the hemispheric differences (HD) in the power of biopotentials (BP) between the homologous EEG leads was used to assess the cerebral energy exchange. There is evidence of the cerebral energy exchange increase in the anterior cortical areas of individuals with the low degree of PPA. The increased cerebral energy exchange has been also revealed in SFU-1 and SFU-2 responsible for the mental and psychophysiological functions of the CNS. However, cerebral energy exchange remains unchanged in the SFU-3 reflecting the central control of the CVS.

Brain Glucose Metabolism in Cerebral Amyloid Angiopathy: An FDG-PET Study.

The in vivo diagnosis of cerebral amyloid angiopathy (CAA) is currently based on the Boston criteria, which largely rely on hemorrhagic features on brain magnetic resonance imaging. Adding to these criteria 18F-fluoro-deoxy-D-glucose (FDG) positron emission tomography, a widely available imaging modality, might improve their accuracy. Here we tested the hypothesis that FDG uptake is reduced in posterior cortical areas, particularly the primary occipital cortex, which pathologically bear the brunt of vascular Aβ deposition. From a large memory clinic database, we retrospectively included all patients in whom both brain magnetic resonance imaging and FDG positron emission tomography had been obtained as part of routine clinical care and who fulfilled the Boston criteria for probable CAA. None had a history of symptomatic intracerebral hemorrhage. FDG data processing involved (1) spatial normalization to the Montreal Neurology Institute/International Consortium for Brain Mapping 152 space and (2) generation of standardized FDG uptake (relative standardized uptake value; relative to the pons). The relative standardized uptake value data obtained in 13 regions of interest sampling key cortical areas and the cerebellum were compared between the CAA and age-matched control groups using 2 separate healthy subject databases and image-processing pipelines. The presence of significant hypometabolism (2-tailed P<0.05) was assessed for the bilaterally averaged regions-of-interest relative standardized uptake values. Fourteen patients fulfilling the Boston criteria for probable CAA (≥2 exclusively lobar microbleeds) were identified. Significant hypometabolism (P range, 0.047 to <0.0001) consistently affected the posterior cortical areas, including the superior and inferior parietal, primary visual, lateral occipital, lateral temporal, precuneus, and posterior cingulate regions of interest. The anterior cortical areas were marginally or not significantly hypometabolic, and the cerebellum was spared. Supporting our hypothesis, significant glucose hypometabolism predominantly affected posterior cortical regions, including the visual cortex. These findings from a small sample may have diagnostic implications but require replication in larger prospective studies. In addition, whether they generalize to CAA-related symptomatic intracerebral hemorrhage warrants specific studies.

BIOELECTRIC ACTIVITY OF THE BRAIN IN PUPILS WITH DIFFERENT ACADEMIC SUCCESS. REPORT 2. THE RELATIONSHIP BETWEEN THE ACADEMIC SUCCESS AND PATTERNS OF BIOELECTRIC ACTIVITY OF THE CORTEX

Background. The paper presents the study of the factors of academic success and failure in students, which is a relevant and socially significant problem. Academic failure often results in behavior deviations, drug abuse and other types of dangerous behavior. Therefore, it is of utmost importance to establish the reasons of academic failure, as well as the ways to improve academic performance. Aim. The paper aims to establish the features of responses of academically successful and unsuccessful 12-year-old children to cognitive load based on EEG data. Materials and methods. Twelve-year-old schoolchildren (n = 51) from Ekaterinburg participated in the study. Participants were divided into two groups depending on their academic performance. EEG recording was performed using the CONAN-m equipment (Informatics and Computers, Russia). Monopolar EEG recordings were obtained from 10 symmetrical leads in different conditions: during resting wakefulness (for eyes open and closed) and when solving experimental tasks of three types (simple arithmetic task, verbal and logical task, spatial thinking task). The differences between the samples of academically successful and unsuccessful children were assessed using the Wilcoxon nonparametric test. Results. Differences were revealed in a number of EEG indicators both at rest and when solving experimental tasks between academically successful and unsuccessful schoolchildren. The responses of academically successful children to cognitive load were characterized by predominant ctivation of the anterior cortical areas with a focus of activity in the left frontal area. Academically unsuccessful children were characterized by a more generalized type of EEG response with a focus of activity in the caudal areas of the cortex, especially when solving a figure rotation task. It was also found that successful children made mistakes when solving a figure rotation task and unsuccessful ones-when solving verbal and logical tasks. Conclusion. Children with low academic success were found to have characteristic features of the functioning of the cerebral cortex, which hampered the perception of educational material presented in the form of a logically structured message. However, these children were able to brilliantly operate with visual-spatial information. This must be taken into account when working with such children to improve their academic performance.

Suppression of the Swallowing Reflex during Rhythmic Jaw Movements Induced by Repetitive Electrical Stimulation of the Dorsomedial Part of the Central Amygdaloid Nucleus in Rats.

A previous study indicated that the swallowing reflex is inhibited during rhythmic jaw movements induced by electrical stimulation of the anterior cortical masticatory area. Rhythmic jaw movements were induced by electrical stimulation of the central amygdaloid nucleus (CeA). The swallowing central pattern generator is the nucleus of the solitary tract (NTS) and the lateral reticular formation in the medulla. Morphological studies have reported that the CeA projects to the NTS and the lateral reticular formation. It is therefore likely that the CeA is related to the control of the swallowing reflex. The purpose of this study was to determine if rhythmic jaw movements driven by CeA had inhibitory roles in the swallowing reflex induced by electrical stimulation of the superior laryngeal nerve (SLN). Rats were anesthetised with urethane. The SLN was solely stimulated for 10 s, and the swallowing reflex was recorded (SLN stimulation before SLN + CeA stimulation). Next, the SLN and the CeA were electrically stimulated at the same time for 10 s, and the swallowing reflex was recorded during rhythmic jaw movements (SLN + CeA stimulation). Finally, the SLN was solely stimulated (SLN stimulation following SLN + CeA stimulation). The number of swallows was reduced during rhythmic jaw movements. The onset latency of the first swallow was significantly longer in the SLN + CeA stimulation than in the SLN stimulation before SLN + CeA stimulation and SLN stimulation following SLN + CeA stimulation. These results support the idea that the coordination of swallowing reflex with rhythmic jaw movements could be regulated by the CeA.

Co-localization of two-color rAAV2-retro confirms the dispersion characteristics of efferent projections of mitral cells in mouse accessory olfactory bulb.

The accessory olfactory bulb (AOB), located at the posterior dorsal aspect of the main olfactory bulb (MOB), is the first brain relay of the accessory olfactory system (AOS), which can parallelly detect and process volatile and nonvolatile social chemosignals and mediate different sexual and social behaviors with the main olfactory system (MOS). However, due to its anatomical location and absence of specific markers, there is a lack of research on the internal and external neural circuits of the AOB. This issue was addressed by single-color labeling and fluorescent double labeling using retrograde rAAVs injected into the bed nucleus of the stria terminalis (BST), anterior cortical amygdalar area (ACo), medial amygdaloid nucleus (MeA), and posteromedial cortical amygdaloid area (PMCo) in mice. We demonstrated the effectiveness of this AOB projection neuron labeling method and showed that the mitral cells of the AOB exhibited efferent projection dispersion characteristics similar to those of the MOB. Moreover, there were significant differences in the number of neurons projected to different brain regions, which indicated that each mitral cell in the AOB could project to a different number of neurons in different cortices. These results provide a circuitry basis to help understand the mechanism by which pheromone information is encoded and decoded in the AOS.

Neurophysiological and behavioral correlates of alertness impairment and compensatory processes in ADHD evidenced by the Attention Network Test.

In Attention Deficit Hyperactivity disorder (ADHD), fMRI studies show asymmetric alterations: widespread hypoactivation in anterior cortical areas and hyperactivation in some posterior regions, and the latter is considered to be related to compensatory processes. In Posner’s attentional networks, an important role is attributed to functional interhemispheric asymmetries. The psychophysiological Attention Network Test (ANT), which measures the efficiency of the alerting, orienting, and executive networks, seems particularly informative for ADHD. Potentials related to ANT stimuli (ANT-RPs) have revealed reduced cognitive potential P3 in ADHD. However, there are no studies associated with asymmetry of ANT-RPs. In the present study, conducted with 20 typically developing boys and 19 boys with ADHD, aged 11–13 years, the efficiency of the three Posner’s networks regarding performance and amplitude asymmetries in ANT-RPs was evaluated according to the arithmetic difference of these parameters between different cue and target presentation conditions. The results were correlated to Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) scores. Regarding accuracy and intraindividual variation in reaction time, ADHD subjects showed lower efficiency of executive and alerting network, and this effect was correlated with DSM. Regarding alerting network, ANT-RPs in ADHD did not have the right-side amplitude prevalence in the temporal regions, which was observed in controls. In all ANT conditions, significantly higher asymmetries were observed in ADHD than in controls in the occipital regions 40–200 ms after target onset. Their amplitude in ADHD subjects was inversely proportional to DSM scores of inattentiveness and directly proportional to accuracy and efficiency of the executive network. The results suggest impaired alerting and executive networks in ADHD and compensatory occipital mechanisms.

P09-F Anterior EEG slowing in Dementia with Lewy Bodies: A multicenter European cohort study

Background EEG slowing with pre-alpha dominant frequency in posterior derivations is a supportive biomarker for Dementia with Lewy Bodies diagnosis, with high predictive value for the differential diagnosis with Alzheimer’s Disease. The appearance of a pre-alpha rhythm is considered to be linked to a dysfunctional thalamo-cortical connection. We hypothesize that the intra-subject evaluation would give information on possible different involvement of anterior and posterior cortical areas in Dementia with Lewy Bodies. Objectives Our aim was to analyse the anterior-posterior scalp distribution of dominant frequencies with an intra-subject evaluation in a dementia with Lewy bodies patient group. Methods We quantitatively analyzed EEGs of 122 patients from 5 Centers of the European dementia with Lewy bodies Consortium. EEG spectra values, divided into delta, theta, pre-alpha, alpha frequency bands were described by dominant frequency, dominant frequency variability, frequency prevalence. Results Dominant frequency in anterior derivations was lower than in posterior derivations (p = 2 · 10–4). Dominant frequency variability, frequency prevalence in delta and theta was higher in anterior derivations (3 · 10–7; 1 · 10–16; 1 · 10–5). As a consequence, frequency prevalence in pre-alpha and alpha was lower in anterior than posterior derivations (4 · 10–3; 1 · 10–7), due to the prevalence of delta/theta in anterior derivations. In 11% of patients, pre-alpha was dominant in anterior leads while alpha rhythm was still dominant in posterior derivations. Conclusions EEG slowing was more severe in anterior derivations. A future longitudinal study should address the possibility that the anterior EEG abnormalities appear earlier in the disease course.

Weekly teriparatide treatment increases vertebral body strength by improving cortical shell architecture in ovariectomized cynomolgus monkeys.

Weekly teriparatide treatment is reported to reduce the incidence of osteoporotic vertebral fractures. However, the effect of weekly teriparatide on cortical bone has not been clarified. This study aimed to examine the effects of weekly teriparatide treatment on bone mass, intracortical structure, and remodeling of the lumbar vertebral cortical shell and its relation to mechanical properties in ovariectomized cynomolgus monkeys. Female monkeys, aged 9 to 15 years, were divided into four groups: (1) SHAM group, (2) ovariectomized group (OVX group), (3) OVX with 1.2 μg/kg once-weekly teriparatide group (LOW group), (4) OVX with 6.0 μg/kg once-weekly teriparatide group (HIGH group). After 18 months, all animals were double-labeled with calcein, and lumbar vertebrae were analyzed with histomorphometry and compressive mechanical tests. Following ovariectomy, we found reductions in the anterior cortical shell area of the vertebrae and reductions in nearly all of the tested vertebral mechanical properties. Weekly teriparatide significantly preserved the anterior cortical shell area and the energy absorption capacity of the lumbar vertebrae in a dose-dependent manner. Multiple regression analyses indicated that improved mechanical properties were more associated with the increased anterior cortical shell area rather than the cancellous bone volume. The intracortical structure of the Haversian canals was also preserved following teriparatide treatment after ovariectomy. These findings suggest the importance of the cortical shell as a therapeutic target in the treatment of osteoporosis. Weekly teriparatide treatment increases the compressive mechanical strength of the lumbar vertebrae by thickening the anterior cortical shell.

Morphological changes in subregions of hippocampus and amygdala in major depressive disorder patients.

Despite many neuroimaging studies in the past years, the neuroanatomical substrates of major depressive disorder (MDD) subcortical structures are still not well understood. Since hippocampus and amygdala are the two vital subcortical structures that most susceptible to MDD, finding the evidence of morphological changes in their subregions may bring some new insights for MDD research. Combining structural magnetic resonance imaging (MRI) with novel morphometry analysis methods, we recruited 25 MDD patients and 28 healthy controls (HC), and investigated their volume and morphological differences in hippocampus and amygdala. Relative to volumetric method, our methods detected more significant global morphological atrophies (p<0.05). More precisely, subiculum and cornu ammonis (CA) 1 subregions of bilateral hippocampus, lateral (LA) and basolateral ventromedial (BLVM) of left amygdala and LA, BLVM, central (CE), amygdalostriatal transition area (ASTR), anterior cortical (ACO) and anterior amygdaloid area (AAA) of right amygdala were demonstrated prone to atrophy. Correlation analyses between each subject's surface eigenvalues and Hamilton Depression Scale (HAMD) were then performed. Correlation results showed that atrophy areas in hippocampus and amygdala have slight tendencies of expanding into other subregions with the development of MDD. Finally, we performed group morphometric analysis and drew the atrophy and expansion areas between MDD-Medicated group (only 19 medicated subjects in MDD group were included) and HC group, found some preliminary evidence about subregional morphological resilience of hippocampus and amygdala. These findings revealed new pathophysiologic patterns in the subregions of hippocampus and amygdala, which can help with subsequent smaller-scale MDD research.

ЭФФЕКТ АГОНИСТА РЕЦЕПТОРА TAAR5 СЛЕДОВЫХ АМИНОВ КАК МОДЕЛЬ ШИЗОФРЕНИИ ПО ДАННЫМ ЭЛЕКТРОКОРТИКОГРАФИИ КРЫС

The effect of a-NETA, a TAAR5 trace amines receptor agonist, on ECOG was evaluated in chronic experiments in rats. Based of the role of gamma oscillations in the transmission of information between brain regions that is presumed to be affected by schizophrenia, the changes in the spatial synchronization in the gamma range, as well as the speciral power of the main ECoG rhythms, were separately estimated. In order to examine the topography of the entire cortex, 6 low-resistance electrodes were implanted in two rows of 3 in the cortex of both hemispheres of Adult Wistar male rats. Twenty experiments were performed: in 10 experiments, a-NETA was systemically administered, the saline was administered in other 10. Injection of a-NETA caused an increase in the power in the delta range of 0—5 Hz, coupled with a power reduction in the range of 5—10 Hz. The maximum differences were observed in the first 10 minutes. No differences were observed after the saline injections. The described growth of slow waves was accompanied by the decrease in the spatial synchronization of fast gamma-oscillations between all 6 registration points in comparison with the background before the injection, and with control. All effects were more pronounced for the anterior cortical areas. We suggest that a-NETA through effect on TAAR5 influences the dopamine transmission, which in turn disrupts the glutamatergic transmission, resulting in the gamma-synchronization dysfunction.

Individual differences in children’s global motion sensitivity correlate with TBSS-based measures of the superior longitudinal fasciculus

Reduced global motion sensitivity, relative to global static form sensitivity, has been found in children with many neurodevelopmental disorders, leading to the “dorsal stream vulnerability” hypothesis (Braddick et al., 2003). Individual differences in typically developing children’s global motion thresholds have been shown to be associated with variations in specific parietal cortical areas (Braddick et al., 2016). Here, in 125 children aged 5–12years, we relate individual differences in global motion and form coherence thresholds to fractional anisotropy (FA) in the superior longitudinal fasciculus (SLF), a major fibre tract communicating between parietal lobe and anterior cortical areas. We find a positive correlation between FA of the right SLF and individual children’s sensitivity to global motion coherence, while FA of the left SLF shows a negative correlation. Further analysis of parietal cortical area data shows that this is also asymmetrical, showing a stronger association with global motion sensitivity in the left hemisphere. None of these associations hold for an analogous measure of global form sensitivity. We conclude that a complex pattern of structural asymmetry, including the parietal lobe and the superior longitudinal fasciculus, is specifically linked to the development of sensitivity to global visual motion. This pattern suggests that individual differences in motion sensitivity are primarily linked to parietal brain areas interacting with frontal systems in making decisions on integrated motion signals, rather than in the extra-striate visual areas that perform the initial integration. The basis of motion processing deficits in neurodevelopmental disorders may depend on these same structures.

Zygomatic Arch Cortical Area and Diet in Haplorhines.

The influence that various types of ingested foods have on the form (size and shape) of specific features of the masticatory system is an area in which many questions remain unanswered. The bony zygomatic arch, the focus of this study, is directly linked to the masticatory system because it serves as the anchor for the masseter muscle, a primary muscle of chewing and source of masticatory force. However, the influence of diet and the forces associated with different diet types on the arch's internal bone architecture is not well understood. Despite the breadth of work centered around the craniofacial complex and biomechanics of mastication, there is a need for further investigations into the functional relationships between specific bony features that experience high strains, (e.g., the zygomatic arch), and the masticatory forces generated by different diets (e.g., mechanically resistant versus non- mechanically resistant) across non-human primates. A hypothesis and series of predictions assessing diet in relation to variability in cortical area distributions and values of section moduli (measures of bone strength) throughout the zygomatic arch were tested in a sample of haplorhine primates. Cortical area and measures of section moduli appear to track with the known masticatory strain distribution along the zygomatic arch. Pairwise comparisons between closely related taxa of different diets reveal significant differences in anterior cortical area and section moduli values. These results imply that differences in masticatory loading due to diet manifest in the zygomatic arch's internal bone structure. Anat Rec, 299:1789-1800, 2016. © 2016 Wiley Periodicals, Inc.

70. Rehabilitation of verbal and visuospatial memory by oscillatory tDCS and sleep consolidation

Temporal lobe epilepsy (TLE) is often associated with memory deficits. Given the putative role for sleep spindles in learning and encoding, the distribution of spindle generators skewed toward the affected lobe in TLE subjects may be a neurophysiological marker of defective memory. Slow-oscillatory transcranial direct current stimulation (sotDCS) has been shown to improve memory possibly by increasing slow-wave sleep and modulating sleep spindles. To test if excitatory anodal sotDCS over the affected temporal lobe affects sleep spindles, thus improving memory performance. In this randomized controlled cross-over study 12 people with TLE underwent either sotDCS (0.75 Hz; 0–250 μV, 30 min) or a sham procedure before a daytime nap. Declarative verbal and visuospatial learning were tested. Fast and slow spindle signals were recorded by 256-channel EEG during sleep. In both study arms, we used electrical source imaging (ESI) to localize cortical generators. Neuropsychological data were analyzed with general linear model statistics or the Kruskal–Wallis test (p or Z < 0.05), and neurophysiological data were tested with the Mann–Whitney t test and a binomial distribution test (p or Z < 0.05). An improvement in declarative (p = 0.05) and visuospatial memory performance (p = 0.048) was noted after sotDCS. SotDCS increased the current density of slow spindle generators (Z = 0.001), with a shift to the anterior cortical areas. Anodal sotDCS delivered over the affected temporal lobe can improve declarative and, to a lesser extent, visuospatial memory performance by modulating cortical source generators of slow sleep spindles. SotDCS appears to be a promising tool for memory rehabilitation in people with TLE.

Iliopsoas tendon insertion footprint with surgical implications in lesser trochanterplasty for treating ischiofemoral impingement: an anatomic study.

The objective of this study was to describe the footprint location of the iliopsoas tendon on the lesser trochanter to clarify the surgical implications of the lesser trochanterplasty for treating ischiofemoral impingement. Ten non-matched, fresh-frozen, cadaveric hemipelvis specimens (average age, 62.4 years; range, 48–84 years; 7 male and 3 female) were included. Registered measures included bony parameters of the lesser trochanter (lesser trochanteric area, distances from the tip to the base in a coordinate system, height and area) and tendinous iliopsoas footprint descriptions (areas and detailed location). The mean height of the lesser trochanter was 13.1 (SD ± 1.8) mm, with female having a smaller lesser trochanter on average (11.3, SD ± 2.0). A double tendinous footprint was found in 7 (70%) specimens. The average area of the single- and double-footprint was 211.2 mm2 and 187.9 mm2, respectively. An anterior cortical area with no tendinous insertion on the anterior aspect of lesser trochanter was present in all specimens and measured 4.9 mm (SD ± 0.6) on average. The mean ratio between the bald anterior wall and the lesser trochanter height was 38% (SD ± 0.05). The iliopsoas tendon footprint is double (psoas and iliacus) in most cases and is located on the anteromedial tip of the lesser trochanter. A bald anterior wall on the bottom of the lesser trochanter indicates that a partial or total lesser trochanterplasty for increasing the ischiofemoral space without detaching partially or entirely the iliopsoas tendon is improbable.

P65. Memory rehabilitation in temporal lobe epilepsy: Slow-oscillatory transcranial direct current stimulation modulates memory by altering sleep spindle generators

Background Temporal lobe epilepsy (TLE) is often associated with memory deficits. Given the putative role for sleep spindles in learning and encoding, the distribution of spindle generators skewed toward the affected lobe in TLE subjects may be a neurophysiological marker of defective memory. Slow-oscillatory transcranial direct current stimulation (sotDCS) has been shown to improve memory possibly by increasing slow-wave sleep and modulating sleep spindles. Objective/Hypothesis To test if excitatory anodal sotDCS over the affected temporal lobe affects sleep spindles, thus improving memory performance. Methods In this randomized controlled cross-over study 12 people with TLE underwent either sotDCS (0.75 Hz; 0–250 μV, 30 min) or a sham procedure before a daytime nap. Declarative verbal and visuospatial learning were tested. Fast and slow spindle signals were recorded by 256-channel EEG during sleep. In both study arms, we used electrical source imaging (ESI) to localize cortical generators. Neuropsychological data were analyzed with general linear model statistics or the Kruskal–Wallis test (p or Z). Results An improvement in declarative (p = 0.05) and visuospatial memory performance (p = 0.048) was noted after sotDCS. SotDCS increased the current density of slow spindle generators (Z = 0.001), with a shift to the anterior cortical areas. Conclusions Anodal sotDCS delivered over the affected temporal lobe can improve declarative and, to a lesser extent, visuospatial memory performance by modulating cortical source generators of slow sleep spindles. SotDCS appears to be a promising tool for memory rehabilitation in people with TLE ( Fig. 1 , Table 1 , Table 2 ).

Slow-oscillatory Transcranial Direct Current Stimulation Modulates Memory in Temporal Lobe Epilepsy by Altering Sleep Spindle Generators: A Possible Rehabilitation Tool.

Temporal lobe epilepsy (TLE) is often associated with memory deficits. Given the putative role for sleep spindles memory consolidation, spindle generators skewed toward the affected lobe in TLE subjects may be a neurophysiological marker of defective memory. Slow-oscillatory transcranial direct current stimulation (sotDCS) during slow waves sleep (SWS) has previously been shown to enhance sleep-dependent memory consolidation by increasing slow-wave sleep and modulating sleep spindles. To test if anodal sotDCS over the affected TL prior to a nap affects sleep spindles and whether this improves memory consolidation. Randomized controlled cross-over study. 12 people with TLE underwent sotDCS (0.75 Hz; 0-250 μV, 30 min) or sham before daytime nap. Declarative verbal and visuospatial learning were tested. Fast and slow spindle signals were recorded by 256-channel EEG during sleep. In both study arms, electrical source imaging (ESI) localized cortical generators. Neuropsychological data were analyzed with general linear model statistics or the Kruskal-Wallis test (P or Z < 0.05), and neurophysiological data tested with the Mann-Whitney t test and binomial distribution test (P or Z < 0.05). An improvement in declarative (P = 0.05) and visuospatial memory performance (P = 0.048) emerged after sotDCS. SotDCS increased slow spindle generators current density (Z = 0.001), with a shift to the anterior cortical areas. Anodal sotDCS over the affected temporal lobe improves declarative and visuospatial memory performance by modulating slow sleep spindles cortical source generators. SotDCS appears a promising tool for memory rehabilitation in people with TLE.

Maturation of Cortico-Subcortical Structural Networks--Segregation and Overlap of Medial Temporal and Fronto-Striatal Systems in Development

The brain consists of partly segregated neural circuits within which structural convergence and functional integration occurs during development. The relationship of structural cortical and subcortical maturation is largely unknown. We aimed to study volumetric development of the hippocampus and basal ganglia (caudate, putamen, pallidum, accumbens) in relation to volume changes throughout the cortex. Longitudinal MRI data were obtained across a mean interval of 2.6 years in 85 participants with an age range of 8-19 years at study start. Left and right subcortical changes were related to cortical change vertex-wise in the ipsilateral hemisphere with general linear models with age, sex, interval between scans, and mean cortical volume change as covariates. Hippocampal-cortical change relationships centered on parts of the Papez circuit, including entorhinal, parahippocampal, and isthmus cingulate areas, and lateral temporal, insular, and orbitofrontal cortices in the left hemisphere. Basal ganglia-cortical change relationships were observed in mostly nonoverlapping and more anterior cortical areas, all including the anterior cingulate. Other patterns were unique to specific basal ganglia structures, including pre-, post-, and paracentral patterns relating to putamen change. In conclusion, patterns of cortico-subcortical development as assessed by morphometric analyses in part map out segregated neural circuits at the macrostructural level.

I finally see what you see: Parkinson's disease visual hallucinations captured with functional neuroimaging

Functional neuroimaging studies have described alterations in neural activation in PD patients with chronic hallucinations. These studies have not, however, captured neural activation patterns during an actual hallucinatory event. The objective of this work was to investigate neuroanatomical substrates active during visual hallucinations in a patient with Parkinson's disease (PD). We conducted an event-related functional magnetic resonance imaging (fMRI) case-study examination of a 66-year-old male PD patient with stereotypic, chronic, and frequent visual hallucinations. The patient reported 16 hallucinations during the fMRI scan. Increased activation during hallucinations was found in the cingulate, insula, frontal lobe, thalamus, and brain stem. Decreased activation was found in the lingual and fusiform gyri, inferior occipital gyrus, and middle frontal and superior temporal lobes. To our knowledge, this report is the first published case documenting the cortical activation patterns using fMRI techniques in a PD patient during active hallucinations. Our results suggest that during a visual hallucination, a marked desynchronization occurs between posterior and anterior cortical areas involved in visual processing.