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14 Sep 1996: Purely by accident, as I sought some respite from my usual goofing off, I happened to catch part of today's Life And Times program on KCET, our local PBS TV station- and was astonished to watch an interview with the principal author of some fascinating new work on memory and PD, exactly the same work which I had seen in the current (6 September) issue of Science, and which I had already written up for the October 1996 Current Science Reviews. For the benefit of local listmembers who might also have watched the same show and want to know more, I append those reviews here. Transcripts of the show are available from KCET, but the interview actually contained little beyond the CSR review. To dig deeper, one should consult the Science articles that are cited: CURRENT SCIENCE REVIEWS by Joe Bruman October 1996 p.1 of x Knowlton B et al; Science, 6 Sep 1996:1399-1402: PD patients and amnesiacs were given a gambling-type test where they had to predict an outcome based on cues whose appearance was random in order and variable in accuracy. The amnesiacs learned to predict well, but forgot the training session; PD patients recalled the training well but could not learn to predict. They were at a fairly late stage (H-Y average 2.8) and under various regimes of dopamine-enhancement therapy. Robbins T; Science, 6 Sep 1996: 1263-1264: PD impairs memory (as you always suspected). Declarative memory (of events, facts, and shapes) resides in the temporal lobes and is unaffected. Non-declarative memory, (the ability to learn habits, skills, or judgement through repeated experience or practice) seems to reside in the caudate and putamen, and is impaired in PD patients. The effect of compensation for the loss or of dopamine enhancement is still uncertain. Science News, 7 Sep 1996:150 (news item): Conventional wisdom, that memory loss in aging is due to death of cells in the hippocampus (a formation inside a ventricle of the temporal lobe) is challenged by more careful counting technique in rat brains. Aged rats, with or without memory impairment, had the same number of hippocampal cells as young ones, suggesting that the cells don't die, but only stop functioning. If that is true, there is hope that various brain diseases may be easier to treat. (In another development, workers found on autopsy that the hippocampus of PD patients was on average 25% smaller than normal. Whether that was an effect of PD or a preexisting condition was not determined.) Cheers, Joe J. R. Bruman (818) 789-3694 3527 Cody Road Sherman Oaks CA 91403