Title:Neuromodulation of Memory Formation and Extinction
Volume: 17
Issue: 3
Author(s): Mehmet Bostanciklioğlu*
Affiliation:
- Elysium Health Center, Gaziantep,Turkey
Keywords:
Memory formation, memory retrieval, memory extinction, neuropharmacology, serotonin, norepinephrine.
Abstract: Memory retrieval is mediated by discharges of acetylcholine, glutamate, gammaaminobutyric
acid, norepinephrine, and serotonin/5-hydroxytryptamine circuits. These projections
and memory interact through engram circuits, neurobiological traces of memory. Increased excitability
in engram circuits of the medial prefrontal cortex and hippocampus results in remote and
recent memory retrievals, respectively. However, due to degenerated neurotransmitter projections,
the excitability state of engram circuits is decreased in the patient with dementia; and thus, acquired-
memory cannot be retrieved by natural cues. Here, we suggest that artificial neuropharmacological
stimulations of the acquired-memory with an excitation potential higher than a natural
cue can excite engram circuits in the medial prefrontal cortex, which results in the retrieval of lost
memories in dementia. The neuropharmacological foundations of engram cell-mediated memory
retrieval strategy in severe dementia, in line with this has also been explained. We particularly
highlighted the close interactions between periaqueductal gray, locus coeruleus, raphe nuclei, and
medial prefrontal cortex and basolateral amygdala as treatment targets for memory loss. Furthermore,
the engram circuits projecting raphe nuclei, locus coeruleus, and pontomesencephalic tegmentum
complex could be significant targets of memory editing and memory formation in the absence
of experience, and a well-defined study of the neural events underlying the interaction of
brain stem and memory will be relevant for such developments. We anticipate our perspective to
be a starting point for more sophisticated in vivo models for neuropharmacological modulations of
memory retrieval in Alzheimer’s dementia.
