Biomedical subjects

Corinna M Cincotta

Publications and source records attributed to Corinna M Cincotta.

3 recordsLinked to original sources

PubMed2005

Dynamics of frontal, striatal, and hippocampal systems during rule learning.

We examined interactions between frontal, striatal, and hippocampal systems during a rule-learning task. Nineteen healthy young adults solved multiple rule-learning problems requiring hypothesis testing while functional magnetic resonance images were obtained. Activity in the head of the caudate peaked early after the beginning of each problem and then dropped rapidly. In contrast, activity in prefrontal cortex areas reached peak values later. These results are in accordance with theories suggesting that the striatum identifies the behavioral context necessary for the frontal lobe to select an appropriate strategy. Striatal and hippocampal systems showed antagonistic patterns of activity: Activation in the anterior hippocampus decreased, whereas caudate activity increased. Good learners showed higher activity in the body and tail of the caudate than poor learners, whereas learning success correlated negatively with activity in the hippocampus. Activation in the head of the caudate correlated negatively with hippocampal activation, indicating a potential mechanism for hippocampal activity reduction.

Adult↗

PubMed2005

The roles of the caudate nucleus in human classification learning.

The caudate nucleus is commonly active when learning relationships between stimuli and responses or categories. Previous research has not differentiated between the contributions to learning in the caudate and its contributions to executive functions such as feedback processing. We used event-related functional magnetic resonance imaging while participants learned to categorize visual stimuli as predicting "rain" or "sun." In each trial, participants viewed a stimulus, indicated their prediction via a button press, and then received feedback. Conditions were defined on the bases of stimulus-outcome contingency (deterministic, probabilistic, and random) and feedback (negative and positive). A region of interest analysis was used to examine activity in the head of the caudate, body/tail of the caudate, and putamen. Activity associated with successful learning was localized in the body and tail of the caudate and putamen; this activity increased as the stimulus-outcome contingencies were learned. In contrast, activity in the head of the caudate and ventral striatum was associated most strongly with processing feedback and decreased across trials. The left superior frontal gyrus was more active for deterministic than probabilistic stimuli; conversely, extrastriate visual areas were more active for probabilistic than deterministic stimuli. Overall, hippocampal activity was associated with receiving positive feedback but not with correct classification. Successful learning correlated positively with activity in the body and tail of the caudate nucleus and negatively with activity in the hippocampus.

Adult↗

PubMed2002

Striatal activity in concept learning.

Striatal learning systems have been implicated in learning relationships between visual stimuli and outcomes. In the present study, the activity of the striatum during visual concept learning in humans was examined by using functional magnetic resonance imaging (fMRI). Participants performed three concept-learning tasks and a baseline task. The participants were trained to criterion before fMRI scanning on two tasks, verbal and implicit. In the verbal task, classification could be performed on the basis of a simple verbal rule, but in the implicit task, there was no simple verbal rule. The novel-implicit learning task, in which an implicit structure was used, was not encountered by the participants before scanning. Across all three concept-learning tasks, there was significant activation in the striatum, in comparison with the baseline task. The striatum was recruited similarly in classification when the participants had different levels of expertise (novel-implicit vs. verbal and implicit) and were able to verbalize their learning to different degrees (verbal vs. implicit and novel-implicit). There was left lateral occipital activation when learning was implicit (implicit and novel-implicit), but not when learning was easily verbalized (verbal).

Adult↗