Basal Forebrain Transient Cholinergic Signal in Prefrontal Cortex and its Role in Associative Learning
Year: 2018
Type: dissertation
Abstract: Basal forebrain (BF) cholinergic neurons constitute a main neuromodulatory system in the brain and densely innervate to neocortex and hippocampus. Traditionally, acetylcholine (ACh) released from BF cholinergic neurons are thought to slowly influence neuronal network to regulate arousal, attention, and learning and memory. However, accumulating studies report phasic ACh release upon events with innate or learned salience. Thus, the present study investigated its role in acquisition of trace eyeblink conditioning where a preceding tone is paired with an eyelid shock. Here, it was shown that suppressing cholinergic activity in medial prefrontal cortex (mPFC) during eyelid shock facilitated the formation of the tone-shock association. The enhanced learning was accompanied by elevated mPFC network activities indicated by neuronal activity marker, c-Fos. These findings suggest that phasic ACh release does not serve as a reinforcement signal in mPFC. Rather, it may regulate cortical network state by differentially activating local excitatory and inhibitory neurons.
Source: TSpace (University of Toronto)
Author: Gaqi Tu
Language: English
Topic: Memory and Neural Mechanisms
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2908357956