Anatomy and neurophysiology of memory

Memory is the glue that binds our mental life. Memory can be ultra short memory, short term memory and long term memory. A given neural system participates in several forms of memory. Working memory is regarded as the “mental workspace.” Recent experiments show that memory processing during sleep serves an adaptive function. Best studied mechanisms underlying neural plasticity are long term potentiation (LTP) and long term plasticity (LTD). Hippocampal formation (HF) and linked regions of medial temporal lobe (MTL) in interaction with parts of the prefrontal cortex plays a critical role in the encoding of episodic memory. Interaction between the amygdala and the HF is important for emotional memories especially those with a fearful and aversive character. Acetylcholine is the neurotransmitter associated with declarative memory. Neuroimaging has confirmed the importance of basal ganglia and cerebellum for procedural memory. A reduction of activation to a primed stimulus is consistently found either in modality specific regions or in cortical regions like lateral semantic region for semantic priming. Conditioning, both classical and Pavlovian, has been considered as type of implicit memory. Dorsolateral prefrontal cortex (DLPFC) is important for item storage during work. Tests of thought depend on simultaneous storage and manipulation of information that are considered executive in nature. An episodic buffer is thought to play a role in the interface between working and episodic memory.