Processing time not modality dominates shift costs in the modality-shifting effect.

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Shifting attention between visual and auditory stimuli incurs reaction time costs, termed the modality-shifting effect.
• Previous research suggested greater costs when shifting from visual to auditory targets, potentially due to slower visual stimulus identification.
• It remained unclear if these costs were modality-dependent or related to stimulus identification speed.

Purpose of the Study:

• To investigate whether modality-shifting costs are determined by the modality itself or by the identification speed of the stimuli.
• To disentangle the effects of modality versus processing time on attention-shifting costs.

Main Methods:

• Compared switch costs using auditory stimuli identified slower than visual stimuli (inverting previous paradigms).
• Introduced a second condition with low-intensity auditory stimuli to further slow down processing of semantically identical stimuli.
• Analyzed reaction times to assess the impact of processing speed and modality on attention-shifting costs.

Main Results:

• Findings contradicted the notion of inherent difficulty in shifting from visual stimuli.
• Switch costs were reduced when targets were preceded by faster-processed stimuli.
• The degree of cost was dependent on the processing time of surrounding stimuli, not modality per se.

Conclusions:

• Attention-shifting costs are primarily driven by differences in stimulus identification speed, not by the modality of the stimuli.
• Faster processing of preceding stimuli leads to reduced shifting costs.
• The 'modality-shifting effect' is better understood as a 'processing-speed-shifting effect'.