Prefrontal acetylcholine release controls cue detection on multiple timescales

Area of Science:

• Neuroscience
• Cognitive Neuroscience

Background:

• Cortical cholinergic systems, originating from the basal forebrain, extensively innervate the cerebral cortex.
• Acetylcholine (ACh) plays a crucial role in cognitive functions, including attention and learning.

Purpose of the Study:

• To investigate the role of cortical acetylcholine release in cue detection performance.
• To examine the temporal dynamics of cholinergic activity during a cue detection task.

Main Methods:

• Utilized choline-sensitive microelectrodes for subsecond resolution measurement of cortical ACh release in rats.
• Employed behavioral tasks involving cue detection and cholinergic deafferentation of specific cortical regions (mPFC and motor cortex).

Main Results:

• Detected transient, cue-evoked increases in cholinergic activity in the medial prefrontal cortex (mPFC) during successful cue detection.
• Observed no such transients in the motor cortex, suggesting region-specific cholinergic involvement.
• Demonstrated that mPFC cholinergic deafferentation impaired cue detection, while motor cortex deafferentation did not.
• Found that precue cholinergic activity levels predicted subsequent cue detection success or failure.
• Identified that cue-evoked cholinergic transients were modulated by slower, minute-timescale changes in cholinergic activity.

Conclusions:

• Cortical cholinergic neurotransmission is dynamically regulated on multiple timescales to facilitate the detection of behaviorally significant cues.
• Medial prefrontal cortex cholinergic activity is essential for successful cue detection and cognitive performance.