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Individuals suffering from pathological gambling (PG) show impaired decision making, but it is still not clear how this impairment is related to other traits and neuroanatomical characteristics. In this study, we investigated how the influence of PG on decision making (1) is connected to different impulsivity facets and (2) how it is related to gray matter volume (GMV) in various brain regions. Twenty-eight diagnosed PG patients and 23 healthy controls completed the cups task to measure decision making. In this task, participants had to decide between safe and risky options, which varied in expected value (EV) between risk advantageous, equal EV, and risk disadvantageous choices. A delay discounting task and the Barrant Impulsiveness Scale were applied to assess multiple impulsivity facets. In addition, structural magnetic resonance images were acquired. In comparison to the control group PG patients demonstrated more deficits in decision making, indicated by less EV sensitivity, but there was no significant difference in number of overall risky choices. Also, PG patients showed increased impulsivity in nearly every dimension. Results revealed (1) a positive correlation between decision making impairments and non-planning impulsivity but no significant relation to other impulsivity facets. Although we found no GMV differences between PG patients and controls, (2) a regions of interest analysis showed a correlation between medial orbitofrontal GMV and EV sensitivity in PG patients. Our findings showed that (1) the association between decision making and impulsivity can also be found in PG patients, but only for certain impulsivity facets. This suggests that it is essential to consider measuring different dimensions, when investigating impulsivity in a PG sample. Secondly, our findings revealed that (2) dysfunctional decision making-particularly the component of risk evaluation-is related to decreased GMV in the medial orbitofrontal cortex, a brain region concerned with processing of rewards. Interestingly, we did not find more risky choices for PG patients, and thus, we assume that decision making deficits in PG are primarily related to risk evaluation, not risk seeking, which is in line with our GMV findings.

Article, Recent findings suggest that Alzheimer's disease (AD) is a disconnection syndrome characterized by abnormalities in large-scale networks. However, the alterations that occur in network topology during the prodromal stages of AD, particularly in patients with stable mild cognitive impairment (MCI) and those that show a slow or faster progression to dementia, are still poorly understood. In this study, we used graph theory to assess the organization of structural MRI networks in stable MCI (sMCI) subjects, late MCI converters (lMCIc), early MCI converters (eMCIc), and AD patients from 2 large multicenter cohorts: ADNI and AddNeuroMed. Our findings showed an abnormal global network organization in all patient groups, as reflected by an increased path length, reduced transitivity, and increased modularity compared with controls. In addition, lMCIc, eMCIc, and AD patients showed a decreased path length and mean clustering compared with the sMCI group. At the local level, there were nodal clustering decreases mostly in AD patients, while the nodal closeness centrality detected abnormalities across all patient groups, showing overlapping changes in the hippocampi and amygdala and nonoverlapping changes in parietal, entorhinal, and orbitofrontal regions. These findings suggest that the prodromal and clinical stages of AD are associated with an abnormal network topology., published version, peerReviewed

Unbalanced epigenetic regulation is thought to contribute to the progression of several neurodegenerative diseases, including Huntington’s disease (HD), a genetic disorder considered as a paradigm of epigenetic dysregulation. In this review, we attempt to address open questions regarding the role of epigenetic changes in HD, in the light of recent advances in neuroepigenetics. We particularly discuss studies using genome-wide scale approaches that provide insights into the relationship between epigenetic regulations, gene expression and neuronal activity in normal and diseased neurons, including HD neurons. We propose that cell-type specific techniques and 3D-based methods will advance knowledge of epigenome in the context of brain region vulnerability in neurodegenerative diseases. A better understanding of the mechanisms underlying epigenetic changes and of their consequences in neurodegenerative diseases is required to design therapeutic strategies more effective than current strategies based on HDAC inhibitors. Researches in HD may play a driving role in this process.

Motivation is a hallmark of healthy aging, but the motivation to engage in effortful behavior diminishes with increasing age. Most neurobiological accounts of altered motivation in older adults assume that these deficits are caused by a gradual decline in brain tissue, while some psychological theories posit a switch from gain orientation to loss avoidance in motivational goals. Here, we contribute to reconcile the psychological and neural perspectives by providing evidence that the frontopolar cortex (FPC), a brain region involved in cost–benefit weighting, increasingly underpins effort avoidance rather than engagement with age. Using anodal transcranial direct current stimulation together with effort–reward trade-offs, we find that the FPC’s function in effort-based decisions remains focused on cost–benefit calculations but appears to switch from reward-seeking to cost avoidance with increasing age. This is further evidenced by the exploratory, independent analysis of structural brain changes, showing that the relationship between the density of the frontopolar neural tissue and the willingness to exert effort differs in young vs older adults. Our results inform aging-related models of decision-making by providing preliminary evidence that, in addition to cortical thinning, changes in goal orientation need to be considered in order to understand alterations in decision-making over the life span.

Introduction Although the pre-supplementary motor area (pre-SMA) is one of the most frequently reported areas of activation in functional imaging studies, the role of this brain region in cognition is still a matter of intense debate. Here we present a patient with a focal lesion of caudal pre-SMA who displays a selective deficit in updating a response plan to switch actions, but shows no impairment when required to withhold a response – stopping.

In the January 1984 issue of the Journal of Neuroscience 1 Angel de Blas presents a compelling analysis of the cytoarchitecture of the mammalian cerebellar cortex. While the major workers in this field have contributed the substantial groundwork on which this paper rests, de Blas brings to a well-studied brain region a fresh technical approach that emphasizes some potentially important relationships between neuron and glia. Two of the more fascinating questions addressed by this work are: (1) are the Bergmann glia of the cerebellar cortex involved in helping to establish the well known espalier shape of the Purkinje cell dendrite (flattened in the plane transverse to the long axis of the folium) and (2) do the Bergmann glia in any way serve to orient or guide the granule cell axons (i.e. the parallel fibers of the molecular layer) in a direction perpendicular to the plane of the Purkinje cell dendrite.

Morphine and beta-endorphin inhibit the shaking response of pentobarbital-anesthetized rats to ice water. Stereotaxically guided administration of antibodies to cerebroside sulfate into the periaqueductal gray region, the most sensitive brain region in which to demonstrate inhibition of this response, antagonizes the effect of morphine and beta-endorphin. These results suggest that cerebroside sulfate may be an integral component of an opiate receptor in rat brain.

Quantitative analysis of Golgi-stained neurons in the preoptic area of the brain of prepuberal Macaca fascicularis monkeys indicated structural differences between males and females. Neurons of males had more dendritic bifurcations and a higher frequency of spines. The bifurcation difference appeared in all cell types and was concentrated in the ventrolateral preoptic area. The spine difference was greatest in the central region of the preoptic area. No differences in gross measurements of this brain region were found. These results suggest that sexual dimorphism in the function of the monkey preoptic area may be based on differences in neuronal structure.

Beil-DOPA behandelten Parkinsonpatienten wird gefunden, dass Dopamin und Homovanillinsaure besonders im Striatum akkumuliert wurden. Damit wird die Moglichkeit, dass Dopamin an der Antiparkinson-Wirkung desl-DOPA entscheidend beteiligt ist, in direkter Weise gestutzt.

RACE AND GENDER are being recognized as important factors in the type of stroke a patient experiences, according to New England researchers. Writing on the subject recently, Louis R. Caplan, MD, chair of the Department of Neurology, Tufts University, Boston, said, "A growing body of data suggests that there are important differences in the distribution of occlusive vascular disease in blacks and whites and in men and women" ( Stroke 1986;17:648-655). Caplan amplified on this report at an American Heart Association program in Monterey, Calif. He classified people with strokes into three groups, based on the blood vessel, and therefore the brain region, affected. He added a fourth group that he and colleagues suggest provides data in support of their hypothesis. The first group, of which two thirds are men, has blockage or narrowing of the internal carotid and vertebral arteries, secondary to atherosclerosis. These patients also have a high incidence