Stimulating the parietal cortex by transcranial direct current stimulation (tDCS): no effects on attention and memory

Area of Science:

• Cognitive Neuroscience
• Neuroscience
• Psychology

Background:

• Selective attention is crucial for goal-directed behavior, enabling focus on relevant stimuli and ignoring distractors.
• Attentional focus during encoding influences memory for both targets and distractors, a phenomenon known as memory selectivity.
• Brain imaging implicates the superior parietal cortex (dorsal network) in top-down attention and the inferior parietal cortex (ventral network) in bottom-up attention.

Purpose of the Study:

• To investigate the roles of the dorsal and ventral attentional networks in modulating selective attention and subsequent long-term memory.
• To examine if transcranial direct current stimulation (tDCS) of the left superior and right inferior parietal cortex affects memory selectivity during a task-switching paradigm.

Main Methods:

• Participants underwent transcranial direct current stimulation (tDCS) targeting the left superior and right inferior parietal cortex during a study phase.
• Stimuli (pictures and words) were presented simultaneously, requiring participants to switch between picture and word decisions.
• A subsequent recognition test assessed memory for both target and distractor items.

Main Results:

• The study replicated previous findings that task switching reduces memory selectivity.
• No significant effects of tDCS on memory selectivity were observed.
• This suggests the applied tDCS protocol may not effectively modulate attention during task switching and subsequent memory.

Conclusions:

• The findings question the efficacy of the current tDCS protocol for modulating attentional processes during task switching.
• Further research is needed to explore alternative stimulation parameters or brain regions for influencing attention and memory.
• The study highlights the complexity of attentional network interactions and their impact on memory formation.