Biomedical subjects

Mike Wendt

Publications and source records attributed to Mike Wendt.

4 recordsLinked to original sources

PubMed2006

Visual field x response hand interactions and level priming in the processing of laterally presented hierarchical stimuli.

Hemisphere-specific processing of laterally presented global and local stimulus levels was investigated by (a) examining interactions between the visual field of stimulus presentation and the response hand and (b) comparing intra- with inter-hemispheric effects of level priming (i.e. faster and more accurate performance when the target level repeats). Although in Experiment 1, which involved two-choice responses with left and right hands, performance costs occurred when the same hemisphere received the stimulus and controlled the response hand, further analyses suggest that these effects reflect spatial compatibility rather than intra-hemispheric interference. Consistent with the spatial compatibility interpretation, in Experiment 2 a similar visual field x response interaction was obtained with regard to left and right responses given with the same hand. Trial-to-trial level priming occurred in both experiments and was unaffected by the intra-hemispheric sequence of target levels. Implications regarding hemispheric processing mode are discussed.

Adult↗

PubMed2006

Processing of local and global visual features in obsessive-compulsive disorder.

Research conducted with the Rey-figure task has suggested that patients with obsessive-compulsive disorder (OCD) process local aspects of a complex stimulus more efficiently than the overall gestalt. The aim of the present study was to investigate if this "local bias" is established already during early stimulus encoding or occurs only during later processing, once a percept has been formed (e.g., memory retrieval). To this end, responding to local and global targets of hierarchical letters (e.g., an "E" composed out of small "T"s) was assessed in 30 OCD patients and 28 healthy controls. OCD patients and controls performed comparably on all parameters. These results lend no support to the notion of an early perceptual bias towards local elements in OCD patients. It remains to be tested whether a bias towards local features is confined to situations where local and global features compete for selection.

Adult↗

PubMed2006

Sequential modulations of interference evoked by processing task-irrelevant stimulus features.

Compatibility level repetition benefits in interference paradigms have been taken to reflect enhanced processing selectivity in response to cognitive conflict elicited by a task-irrelevant stimulus feature. The authors demonstrate such sequential effects in the Simon task which (a) occur independent of previous behavioral conflict effects and (b) cannot be accounted for by selectivity enhancement. Furthermore, when presenting more than one type of irrelevant stimulus features, compatibility level repetition effects occurred in a type-specific manner. The results do not support the notion that cognitive conflict results in enhanced processing selectivity and favor a feature integration account.

Adult↗

PubMed2005

Task switching: on the origin of response congruency effects.

When people frequently alternate between simple cognitive tasks, performance on stimuli which are assigned the same response in both tasks is typically faster and more accurate than on stimuli which require different responses for both tasks, thus indicating stimulus processing according to the stimulus-response (S-R) rules of the currently irrelevant task. It is currently under debate whether such response congruency effects are mediated by the activation of an abstract representation of the irrelevant task in working memory or by "direct" associations between specific stimuli and responses. We contrasted these views by manipulating concurrent memory load (Experiment 1) and the frequency of specific S-R associations (Experiment 2). While between-task response congruency effects were not affected by the amount of concurrent memory load, they were much stronger for stimuli that were processed frequently in the context of a competitor task. These findings are consistent with the idea that a large portion of the congruency effects stems from direct S-R associations and they do not support a sole mediation by task-set activation in working memory.

Adult↗