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bioRxiv · 10.1101/356402

Attention to a threat-related feature does not interfere with concurrent attentive feature selection

Abstract

Visual features that are associated with a task and those that predict noxious events both prompt selectively heightened visuocortical responses. Conflicting views exist regarding how the competition between a task-related and a threat-related feature is resolved when they co-occur in time and space. Utilizing aversive differential Pavlovian conditioning, we investigated the visuocortical representation of two simultaneously presented, fully overlapping visual stimuli. Stimuli were isoluminant red and green random dot kinematograms (RDKs) which flickered at two tagging frequencies (8.57 Hz, 12 Hz) to elicit distinguishable steady-state visual evoked potentials (ssVEPs). Occasional coherent motion events prompted a motor response or predicted a noxious noise. These events occurred either in the green (task cue), the red (threat cue), or in both RDKs simultaneously. In an initial habituation phase, participants responded to coherent motion of the green RDK with a key press, but no loud noise was presented at any time. Here, selective amplification was seen for the task-relevant (green) RDK, but interference was observed when both RDKs simultaneously showed coherent motion. Upon pairing the threat cue with the noxious noise in the subsequent acquisition phase, the threat cue-evoked ssVEP (red RDK) was also amplified, but this amplification did not interact with amplification of the task cue, and did not alter the behavioral or visuocortical interference effect seen during simultaneous coherent motion. Results demonstrate that although competing feature conjunctions result in interference in visual cortex, the acquisition of a bias towards an individual threat-related feature does not result in additional cost effects.

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BibTeXRIS

Boylan, M. R., Kelly, M. N., Thigpen, N. N., Keil, A.. 2018-06-27. Attention to a threat-related feature does not interfere with concurrent attentive feature selection. https://doi.org/10.1101/356402

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