1. 1960s, 1970s, converging evidence from cognitive neuropsychology, psychology, neurobiology support the view of Multiple memory systems, efforts to experimentally dissociate memory systems emerged as a central research direction

2. Famous amnesic patient H.M. a. “frankly experimental” brain surgery –a complete bilateral resection of medial temporal lobes (incl. hippocampus and amygdala) for relief of intractable epilepsy. b. Symptoms c. Psychological testing

3. Probe Digit Task 45798348593285

4. Short vs long Term Memory tests Probe digit task, test of HM (Wicklegen, 1968) –45798348593285 Digit span task also showed normal primary memory in HM, 7 plus or minus2 Long term memory tests –HM showed extremely poor ability on tests requiring the retention of verbal information over longer periods of time Conclusion: primary memory exists independently of secondary memory

5. Mirror-tracing task (Brenda Miller, 1965)

6. Declarative vs. Procedural memory HM’s memory problem could not be attributed solely to difficulties with verbal materials i. he had difficult reproducing or recognizing pictures and spatial designs ii. could learn some kinds of information about the verbal materials –(1) e.g. could learn to read works printed mirror- reversed (requiring the ability to deal with abstract rules or procedures)

7. the important distinction is probably not between verbal and motor performance, rather between declarative and procedural memory

8. Declarative memory i. Concept –(1) facts and information acquired through learning –(2) memory that we are aware of accessing ii. include (1) episodic memory: autobiographical, personal history (2) semantic memory: generalized memory, e.g. knowing the meaning of the words

9. Nondeclarative memory (procedural memory) (1) shown by performance rather than by conscious recollection. (2) incl. –(a) skill learning –(b) priming, a change in the processing of a stimulus as a result of prior exposure –(c) conditioning

10. Neuropsychology K. Craik (1943) writes: ‘In any well-made machine one is ignorant of the working of most of the parts - the better they work, the less we are conscious of them... it is only fault which draws attention to the existence of a mechanism at all.’ – from Ellis and Young’s influential book Human Cognitive Neuropsychology (1988).

11. Double dissociation and one-way dissociation

12. Anatomical and neurochemical correlates of neuronal plasticity Two primary goals of learning and memory studies are –i. neural centers involved in specific behaviours –ii. kinds of changes that underly the observed plasticity b. The changes in neural functions (neuronal plasticity) might involve –i. chemistry (the number of transmitter chemicals released), –ii. morphology (the number or types of connections made between nerve cells) –iii. electrical activity (how rapidly, or in what sequence, nerve cells fire)

13. Donald O. Hebb conditions that might be required to produce changes at synapses i. He proposed that functional relationship between a presynatic neuron (A) and a postsynaptic neuron (B) could change if A frequently took part in exciting B. (1) when an axon of cell A is near enough to excite a cell B and repeatedly or persistently takes part in firing it, some growth process or metabolic change takes place in one or both cells suchthat A’s efficacy, as one of the cells firing B, is increased.

14. ii. Extension of the hypothesis: (1) any two cells that are repeated active at the same time will tend to become ‘associated’, so that activity in one facilitates activity in the other. Summary: “Neurons that fire together wire together”

15. Findings by Rosenzweig and associates a. Formal training i. Rats trained and tested for spatial problem task ii. Measured AchE activity in the cerebral cortex iii. Found the groups that had been trained and tested on more difficult problems > those given easier problems > groups given no training and testing. b. Informal learning, enriched experience, i. increased acetylcholinesterase (AchE) ii. increased weights of regions of neocortex.

16. Further systematic testing i. Enriched condition (EC), Standard condition (SC), Isolated condition (IC) ii. training and differential experience could produce measurable changes in the brain Fig 0-8, Fig 0-9 iii. Changes can be produced throughout life span and rather rapidly iv. Change were not uniformly distributed throughout cortex, largest change in occipital cortex

17. Other measures, Fig 0-10 (1) cortical thickness, (2) sizes of neuronal cell bodies, (3) count of dendritic spines Fig 0-11 (4) size of the synaptic contact areas, Fig 0-12, Fig 0-13 (5) increase in extent and branching of dendrites (6) number of synapses per neuron (7) increase in cortical volume and intracortical connections (8) better learning and problem solving