Article history: Accepted 20 June 2007 RE CT ED PR The hippocampus is thought to be critical for encoding contextually bound memories and setting the context for ongoing behavior. However, the mechanisms by which the hippocampal–cortical system controls behavior are poorly understood. We propose a computational model in which the hippocampus exerts contextual control over motivated behavior by ...

The evolution of the dorsomedial nucleus is closely associated with that of the prefrontal cortex. In man and primates this nucleus attains its highest evolutionary level in connection with the strong expansion of the prefrontal cortical lobes. Many authors (Walker 1938, 1940, Waller 1940, Bonin 1948, Pribram, Chow and Semmes 1953, Krieg 1954, ScolloLovizzari and Akert 1963, Akert 1964, Brutkow...

BACKGROUND Previous studies have shown that the activity of the amygdala is elevated in people experiencing clinical and subclinical levels of anxiety and depression (negative affect). It has been proposed that a reduction in inhibitory input to the amygdala from the prefrontal cortex and resultant over-activity of the amygdala underlies this association. Prior studies have found relationships ...

Neuroimaging findings have proposed that some brain regions including the precuneus, posterior cingulate, and medial prefrontal cortex play an essential role of a structural core in the brain. Network organization endures rapid alterations in development with changes in axonal synaptic connectivity, white matter volume, and the thickness of corresponding cortical regions. Structural maturation ...

Lesions of the orbital prefrontal cortex (OPFC) and the nucleus accumbens core (AcbC) can disrupt performance in inter-temporal choice tasks, possibly by increasing the organism's sensitivity to delay and/or magnitude of reinforcement. This experiment examined whether exposure to an inter-temporal choice would induce neuronal activation in these areas, as indicated by enhanced expression of the...

ADHD is a brain based disorder with structural and functional abnormalities in widespread but specific areas of the brain. The most significant and consistent structural imaging findings include smaller total brain volumes, and reduced volumes in the right frontal lobe, right parietal cortex, caudate nucleus, cerebellar hemispheres, and posterior-inferior lobules of the cerebellar vermis. ADHD ...

Accumulating evidence suggests that dysregulation of histone modification is involved in the pathogenesis and/or pathophysiology of psychiatric disorders. However, the abnormalities in histone modification in the animal model of schizophrenia and the efficacy of antipsychotics for such abnormalities remain unclear. Here, we investigated the involvement of histone modification in phencyclidine-i...

Glossary Cognitive control – The organization of thoughts, behaviors, and emotions to achieve selected goals. Conflict – The cognitive state that arises from competition between different behavioral options when only one option may be selected. Dorsolateral prefrontal cortex – An area of the prefrontal cortex that comprises Brodmann’s areas 9 and 46 and that subserves working memory and topdown...

BACKGROUND Schizophrenia has a negative effect on the activity of the temporal and prefrontal cortices in the processing of emotional facial expressions. However no previous research focused on the evaluation of mixed emotions in schizophrenia, albeit they are frequently expressed in everyday situations and negative emotions are frequently expressed by mixed facial expressions. METHODS Altoge...