We review positron emission tomography (PET) studies whose results converge on the hemispheric encoding/retrieval asymmetry (HERA) model of the involvement of prefrontal cortical regions in the processes of human memory. The model holds that the left prefrontal cortex is differentially more involved in retrieval of information from semantic memory, and in simultaneously encoding novel aspects o...

What are the functions of the parietal and prefrontal cortices and how do these regions interact to achieve their objectives? How does context change plans for action? Are 'visual' and 'motor' well-defined attributes of neuronal activity in the association cortex? Recent studies of the saccadic system in monkeys have revealed two sets of paradoxical data: in parietal cortex, activity has visual...

Cognitive models in psychology and neuroscience widely assume that the human brain maintains an abstract representation of tasks. This assumption is fundamental to theories explaining how we learn quickly, think creatively, act flexibly. However, neural evidence for a verifiably generative task has been lacking. Here, report experimental paradigm requires forming such adaptively novel condition...

The purpose of this study was to investigate the effect of stereoscopic display alignment errors on visual fatigue and prefrontal cortical tissue hemodynamic responses. We collected hemodynamic data and perceptual ratings of visual fatigue while participants performed visual display tasks on 8 ft × 6 ft NEC LT silver screen with NEC LT 245 DLP projectors. There was statistical significant diffe...

Glutamate transmission is critical for controlling cortical activity, but the specific contribution of the different isoforms of vesicular glutamate transporters in subcortical pathways to the neocortex is largely unknown. To determine the distribution and neocortical projections of vesicular glutamate transporter2 (Vglut2)-containing neurons, we used in situ hybridization and injections of the...

Though the right prefrontal cortex is often activated in neuroimaging studies of episodic memory retrieval, the functional significance of this activation remains unresolved. In this functional MRI study of 12 healthy volunteers, we tested the hypothesis that one role of the right prefrontal cortex is to monitor the information retrieved from episodic memory in order to make an appropriate resp...

Recent evidence suggests that rewarding and aversive stimuli affect the same brain areas, including medial prefrontal cortex and nucleus accumbens. Although nucleus accumbens is known to respond to salient stimuli, regardless of their hedonic valence, with selective increased dopamine release, little is known about the role of prefrontal cortex in reward- and aversion-related motivation or abou...

The prefrontal cortex subserves executive control--that is, the ability to select actions or thoughts in relation to internal goals. Here, we propose a theory that draws upon concepts from information theory to describe the architecture of executive control in the lateral prefrontal cortex. Supported by evidence from brain imaging in human subjects, the model proposes that action selection is g...

A central issue in cognitive neuroscience concerns the functional architecture of the prefrontal cortex and the degree to which it is organized by sensory domain. To examine this issue, multiple areas of the macaque monkey prefrontal cortex were mapped for selective responses to visual stimuli that are prototypical of the brain's object vision pathway-pictorial representations of faces. Prefron...

Psychostimulant exposure has been shown to cause molecular and cellular changes in prefrontal cortex. It has been hypothesized that these drug-induced changes might affect the operation of prefrontal-limbic circuits, disrupting their normal role in controlling behavior and thereby leading to compulsive drug-seeking. To test this hypothesis, we tested cocaine-treated rats in a fear conditioning,...