This week's articles

Anders Sandberg (asa@nada.kth.se)
23 Dec 1998 00:41:05 +0100

The holiday season is on, and I have been busy with baking and making bifurcation diagrams, so this is a fairly short list of subjects:

British Medical Journal
http://www.bmj.com/current.shtml

This Christmas issue has plenty of fun (not just in fun in the scientific sense but fun in the humorous sense too :-) papers. See especially the study to test the validity of Benjamin Franklin's maxim "early to bed and early to rise makes a man healthy, wealthy, and wise." (http://www.bmj.com/cgi/content/abstract/317/7174/1675), the study of candy consumption and longevity
(http://www.bmj.com/cgi/content/full/317/7174/1683), Xenotransmission
of the socioeconomic gradient in health
(http://www.bmj.com/cgi/content/full/317/7174/1686 yes, the pets of
rich people live longer) and a nice section where they slaughter sacred cows.

And as usual, some more nootropics:

The effects of a low dose of caffeine on cognitive performance Paula J. Durlach Psychopharmacology, 140, pages 116-119 1998

Does a cup of tea affect cognitive performance? It turned out that caffeine in 60mg doses can speed reaction time in pattern recognition, delayed match to sample and visual search.

The effects of black tea and other beverages on aspects of cognition and psychomotor performance
I. Hindmarch, P. T. Quinlan, K. L. Moore and C. Parkin Psychopharmacology (Berl) 139:3 230--238 1998

A look at whether black tea has cognition enhancing effects. Volunteers were given black tea, coffee, caffeinated water, decaffeinated tea and plain water on three times during a day, and the effects were factored. Tea increased performance on the critical flicker fusion test (a measure of how quickly the CNS can distinguish discrete sensory data) within 10 minutes. Caffeine, as expected, prevented the decline in alertness during the day that otherwise occurs but did not in itself alter the CFF threshold. Tea and coffee had similar effects on most other measures. The results suggests that the caffeinated drinks have effects that are independent of caffeine, possibly due to other chemicals, stimulation of the vagus nerve and/or classical conditioning (you know you get more alert when drinking coffee, so you get alert even before the caffeine acts).

Influence of nicotine on simulator flight performance in non-smoker Martin S. Mumenthaler, Joy L. Taylor, Ruth O'Hara and Jerome A. Yesavage Psychopharmacology, 140 pp 38--41, 1998

There is some confusion over whether nicotine helps both smokers and nonsmokers, or just smokers. In this paper nonsmokers given nicotine chewing gum performed significantly better than nonsmokers given placebo on a flight simulator task. The improvement was especially noticeable on the approach to landing, which appears to require sustained attention. One reason the effect was noticeable may be that the participants had already been exposed to nicotine gum, so effects of nausea had gone away; another possibility is that the effect becomes noticeable only for more taxing tasks involving many systems rather than the usual simple tasks in psychophramacological experiments.

Transdermal nicotine effects on attention E. D. Levin, C. K. Conners, D. Silva, S. C. Hinton, W. H. Meck, J. March and J. E. Rose Psychopharmacology (Berl) 140:2 135-41 1998

Another non-smoker experiment. Transdermal nicotine patches (7 mg/day, lowest dose of Nicoderm) increased self-reported mood and attention
(as measured by a computer task).

The suggestion these papers give is that caffeine improves awakeness, while nicotine improves attention. Combining them might however cause tricky reactions, since the arousal level caused by the caffeine will likely lower or raise the dose of nicotine needed for a certain task.

Oxygen and cognitive performance: the temporal relationship between hyperoxia and enhanced memory
M. C. Moss, A. B. Scholey and K. Wesnes
Psychopharmacology (Berl), 140:1 123-126 1998

Yes, oxygen can also improve memory! It seems to act on long-term memory and attention in healthy young adults (but not short-term memory). It turns out that transient oxygen administration enhances memory formation when given up to five minutes before or coincident with the presentation of a series of words.

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Anders Sandberg                                      Towards Ascension!
asa@nada.kth.se                            http://www.nada.kth.se/~asa/
GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y