DANIEL S O'LEARY

..There was no significant rCBF change in the nucleus accumbens or other reward-related brain regions, nor in basal ganglia or hippocampus, which have a high density of cannabinoid receptors...

..Smoking marijuana appears to accelerate a cerebellar clock altering self-paced behaviors...

..These data indicate that marijuana has dramatic direct effects on rCBF, but causes relatively little change in the normal pattern of task-related rCBF on this auditory focused attention task...

..This capacity, critical for social competence, is impaired in schizophrenia. We undertook a study of TOM in a group of patients with schizophrenia and healthy controls...

..These findings indicate altered memory-related brain function in marijuana users...

..Its role in determining cognitive deficits in schizophrenia has also not been systematically studied...

..The authors measured regional cerebral blood flow (rCBF) during performance of a task that required unmedicated patients to recognize the emotional valence of visual images and to determine whether they were pleasant or unpleasant...

..The results of this study demonstrate a cerebral pattern of activation related to Schneiderian symptoms and reinforce the hypothesis of an involvement of cortical areas that mediate space and body representation in such phenomena...

..This adaptive strategy facilitated sequence learning but may have interfered with conventional implicit learning of the overall stimulus pattern...

..In contrast, the reduced flow observed in the frontal and parietal regions may be unique to schizophrenia...

..This study investigated the relationships between duration of untreated initial psychosis and neurocognitive functioning and high-resolution imaging brain measurements...

..Thus, chronic MJ users tend to strongly recruit neural circuitry involved in decision-making and reward processing (vmPFC), and probabilistic learning (cerebellum) when performing the IGT...

..Thus, ventral striatal activity in anticipation of absolute and relative rewards develops with age. Absolute reward processing is also linked to individual differences in Impulsivity...

..These features are described in detail, as well as the reliability of these procedures...

..Specifically, large peaks were noted in cerebellar lobules IV/V, the frontal lobes, and cingulate gyri...

..It will also be the first study to provide information about whether the acute changes in rCBF and cognitive function caused by smoking marijuana become more severe following chronic use of this substance. ..

..Finally, cognitive tasks requiring self-paced timing and other putative cerebellar functions will be used to assess the functional consequences of cerebellar hypoperfusion in chronic users of marijuana. ..

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