Neural correlates of memory updating in the primate prefrontal cortex

Area of Science:

• Neuroscience
• Cognitive Science
• Primate Behavior

Background:

• The primate lateral prefrontal cortex (PFC) is crucial for working memory, involving temporary information storage and manipulation.
• Neuronal mechanisms underlying memory updating within the PFC remain incompletely understood.

Purpose of the Study:

• To investigate neuronal activity in the PFC during the updating of spatial working memory.
• To determine the causal role of PFC neurons in maintaining and updating short-term memories.

Main Methods:

• Macaque monkeys were trained on an oculomotor n-back task involving sequential visual stimuli and saccade generation.
• Neuronal activity was recorded in the PFC, and decoding analyses were performed to predict behavioral choices.
• Electrical stimulation was applied to PFC recording sites to assess its impact on spatial memory.

Main Results:

• Distinct PFC neuronal populations exhibited transient and sustained activity related to memory relevance.
• Decoding analysis successfully predicted future target selection from PFC neuronal activity.
• Electrical stimulation of PFC neurons causally impaired specific spatial memories, highlighting their role in memory updating.

Conclusions:

• PFC neuronal populations encode and update spatial information critical for working memory.
• Prefrontal cortex activity is causally involved in the dynamic maintenance and updating of short-term spatial memories.