Schmolck

Aim

To find out if the semantic long term memory was linked to a certain part of the brain.

If ppts with damaged medial temporal lobes (MTL) and hippocampus would underperform in memory tests because of this.

Sample

14 patients:
(including the case study of HM)

Patient diagnostics

-6 patients with severe damage to the MTL

-3 of above patients with general temporal cortex damage (MTL+)

-8 controls with no brain damage at all

Procedure

9 tests based on photos on either animals or objects -


medial temporal lobe

the tests

-similar pictures: the ppts were given 6 pictures sharing a theme and asked to point out the one that the experimenter named in order to test for confusion

-category fluency: the ppts were asked to give as many examples as possible from each theme

-category sorting: ppts were given all 48 pictures and asked to sort them into man-made or living categories

-definitions: the ppts were given a picture and asked to define it by the theme it fitted into

additional tests on whether objects shown in images were real or not

the ppts were taped and 14 researchers went over the tapes to look for reliability and checked for grammar and syntax errors in the way they talked as this also indicates struggles with semantic memory

Results and Conclusion

In similar pictures, the control group got them all right and so did people with hippocampus damage only, MTL+ patients did worse and achieved 90% or below correct answers, HM got 95% - 100% on this section

MTL+ group did worse overall on all tests

HM did better than the MTL+ patients but slightly worse than the MTL patients

Overall, MTL = 100%, Controls = 99%, MTL+ = 78%

Positive correlation between the amount and damage and the number of mistakes made

Where the hippocampus-only group did better than the control group, Schmolck said this was because they were younger, despite them being matched on this

There is a clear link between damage to the temporal cortex and the loss of semantic memory