Biomedical subjects

A U Turken

Publications and source records attributed to A U Turken.

3 recordsLinked to original sources

PubMed1999

A neuropsychological theory of positive affect and its influence on cognition.

Positive affect systematically influences performance on many cognitive tasks. A new neuropsychological theory is proposed that accounts for many of these effects by assuming that positive affect is associated with increased brain dopamine levels. The theory predicts or accounts for influences of positive affect on olfaction, the consolidation of long-term (i.e., episodic) memories, working memory, and creative problem solving. For example, the theory assumes that creative problem solving is improved, in part, because increased dopamine release in the anterior cingulate improves cognitive flexibility and facilitates the selection of cognitive perspective.

Affect↗

PubMed1999

Response selection in the human anterior cingulate cortex.

The anterior cingulate cortex (ACC) has been proposed as part of the brain's attentional control network, but the exact nature of its involvement in cognitive and motor operations is under debate. Assessing effects of human ACC damage directly addresses the problem of ACC function. We report that executive control processes of a patient with a focal right hemisphere anterior cingulate lesion were not compromised. However, her performance level depended on the response modality used. Under the same task requirements, she was impaired when giving manual responses, but not vocal responses. Thus, we provide neuropsychological evidence for functional specialization within the human ACC.

Attention↗

PubMed1998

A neuropsychological theory of multiple systems in category learning.

A neuropsychological theory is proposed that assumes category learning is a competition between separate verbal and implicit (i.e., procedural-learning-based) categorization systems. The theory assumes that the caudate nucleus is an important component of the implicit system and that the anterior cingulate and prefrontal cortices are critical to the verbal system. In addition to making predictions for normal human adults, the theory makes specific predictions for children, elderly people, and patients suffering from Parkinson's disease, Huntington's disease, major depression, amnesia, or lesions of the prefrontal cortex. Two separate formal descriptions of the theory are also provided. One describes trial-by-trial learning, and the other describes global dynamics. The theory is tested on published neuropsychological data and on category learning data with normal adults.

Adult↗