Constraints on task-based control of behaviour following frontal lobe damage: A single-case study |
| |
Authors: | Alex Bahrami Balani David Soto Glyn W. Humphreys |
| |
Affiliation: | 1. Behavioural Brain Sciences Centre, School of Psychology , University of Birmingham , Birmingham, UK a.b.balani@bham.ac.uk;3. Department of Clinical Neuroscience , Imperial College London , London, UK;4. Behavioural Brain Sciences Centre, School of Psychology , University of Birmingham , Birmingham, UK |
| |
Abstract: | What factors determine stimulus-driven responses in patients with utilization behaviour? We examined this question by assessing the influence of an irrelevant cue on visual search in a patient showing evidence of utilization behaviour (F.K.), following bilateral damage to the medial frontal and temporal lobes. Despite being able to repeat the instructions, F.K. often responded to an item in the search display that matched the cue rather than the target. This effect was reduced under certain conditions: (a) when the cue–search interval increased, (b) when F.K. paid less attention to the cue, and (c) when the target discrimination task was made more difficult. On the other hand, the effect arose even when the cue was always invalid. We suggest that information from the cue competed with the top-down set to determine search. F.K.'s lesion makes it difficult for him to impose top-down knowledge rapidly, leading to responses automatically being based on attended, but irrelevant, cues under short cue–display intervals. |
| |
Keywords: | Task-based control Frontal lobe Utilization behaviour Visual search Selective attention |
|
|