Failure to Affect Decision Criteria During Recognition Memory With Continuous Theta Burst Stimulation

Area of Science:

• Cognitive Neuroscience
• Neuroscience
• Psychology

Background:

• Recognition memory relies on a decision criterion, the minimum evidence needed for recall.
• The neural mechanisms for maintaining this decision criterion are not well understood.
• Prefrontal cortex regions are implicated in decision-making processes.

Purpose of the Study:

• To investigate the neural mechanisms underlying the maintenance of decision criteria in recognition memory.
• To determine if inhibiting specific prefrontal cortex regions using continuous theta burst stimulation (cTBS) alters decision criteria.
• To examine the effects of cTBS on recognition memory performance and discriminability.

Main Methods:

• Participants performed recognition memory tests under conservative and liberal decision criteria.
• Continuous theta burst stimulation (cTBS) was applied to inhibit the right inferior frontal gyrus (rIFG), right middle frontal gyrus (rMFG), and right dorsolateral prefrontal cortex (rDLPFC).
• fMRI was used to identify subject-specific cTBS target sites based on brain activity during memory retrieval.

Main Results:

• cTBS applied to the rIFG, rMFG, and rDLPFC did not significantly alter decision criteria placement.
• Unexpectedly, cTBS to the rDLPFC improved memory discriminability when participants used a liberal decision criterion.
• Recognition memory performance was not significantly affected by cTBS in general.

Conclusions:

• The study failed to demonstrate that cTBS of the targeted prefrontal cortex regions can alter decision criteria in recognition memory.
• The findings suggest a potential role for the rDLPFC in memory discriminability, particularly under liberal criterion settings.
• Further research is needed to explore the neural basis of discriminability in recognition memory.