Temporal aspect of three visual search tasks by using TMS

Area of Science:

• Cognitive Neuroscience
• Neuroscience
• Experimental Psychology

Background:

• Investigating human cognitive processes relies on methods like transcranial magnetic stimulation (TMS).
• The precise timing of neural activity in specific brain regions during visual search remains an area of active research.
• The right posterior parietal cortex's role in visual processing requires further elucidation.

Purpose of the Study:

• To investigate the temporal involvement of the right posterior parietal cortex in visual search using TMS.
• To determine the specific time window during which the right posterior parietal cortex influences visual search performance.
• To differentiate the role of this region in pop-out versus conjunction visual search tasks.

Main Methods:

• Transcranial magnetic stimulation (TMS) was applied to the right posterior parietal cortex at varying stimulus onset asynchronies (SOAs) of 100, 150, and 200 ms after visual stimulus presentation.
• Participants performed visual search tasks, indicating target presence or absence by pressing a mouse button.
• Reaction times were measured to assess task performance under TMS and no-TMS conditions.

Main Results:

• A significant increase in reaction time for target-present trials was observed during pop-out visual search when TMS was applied 150 ms after stimulus presentation.
• No significant differences in reaction time were found for other SOAs or for the conjunction visual search task.
• These findings suggest a specific temporal role for the right posterior parietal cortex in pop-out visual search.

Conclusions:

• The right posterior parietal cortex plays a crucial role in pop-out visual search.
• This involvement occurs approximately 150 ms after visual stimulus presentation.
• The findings highlight the temporal dynamics of neural contributions to visual search strategies.