BHS 499-07Memory and Amnesia

Neuroscience of Memory

Neurons

Memory consists of a change in the structure of neurons that leads to increased likelihood of firing.

Review of neural structure:• CD 2.1 first slide, 2.2 action potential

Long-term Potentiation (LTP) – both short and long-term changes in the brain• CD 13.2 & 13.3 (consolidation)

A Blind Alley

McConnell (1962) – cut up planaria (flatworms) and fed them to other worms who showed the same learning.• McConnell thought memories were encoded

in the RNA, not just the neurons.

• By eating the RNA, the attributes were passed on to another being (or person).

His results were not replicated (not true).

Larger Structures

Semantic memory is structured based on shared meaning, not prior associations.• Similar concepts in terms of meaning are

stored closer to each other.

• Semantic “closeness” is metaphoric, based on response times.

Activation spreads to related items. A great deal of repeated use moves

items from episodic to semantic memory.

Influences on Memory

Alcohol – Bits & Pieces Stress -- Kolb & Whishaw Seg 32 (CD 2) Diabetes – Kolb & Whishaw Ch 13 Seg 6

(CD 3)