Nicotine patches improve mood and response speed in a lexical decision task.

The effects of smoking a cigarette or wearing a transdermal nicotine patch on mood and lexical decision-making were tested in eight smokers. Each participant was tested after 4 hours of smoking abstinence, under 4 conditions: placebo (very low nicotine) cigarette, nicotine cigarette, placebo patch, and nicotine patch. Relative to placebo, wearing the nicotine patch reduced Profile of Mood States (POMS) Total Mood Disturbance and Fatigue/Inertia scores, while increasing the speed of some types of lexical decisions. Smoking a nicotine cigarette did not affect reaction times, but unexpectedly decreased the accuracy of Word/ Nonword lexical decisions. Thus, transdermal nicotine may improve mood and facilitate longterm memory search and/or attentional processes in nicotine-deprived smokers.

Low body temperature in long-lived Ames dwarf mice at rest and during stress.

Among homeothermic animals, larger species generally have lower metabolic rates and live longer than do smaller species. Because Ames dwarf mice (dwarfs) live approximately 1 year longer than their larger normal sex- and age-matched siblings (normals), we hypothesized that they would have lower body core temperature (Tco). We, therefore, measured Tco of six dwarfs and six normals during 24-h periods of ad lib feeding, 24-h food deprivation, and emotional stress induced by cage switching. With ad lib feeding, Tco of dwarfs averaged 1.6 degrees C lower than normals; during food deprivation, Tco of both dwarfs and controls was significantly lower than when food was available ad lib; and following cage switch, Tco was elevated in both groups. However, during all three experiments, Tco was significantly lower in dwarfs than in normals. These data support the hypothesis that Ames dwarf mice, which live longer than normal size controls, maintain lower Tco than normals. Because dwarfs are deficient in thyroid stimulating hormone (TSH) and growth hormone (GH), their low Tco may be a result of reduced thermogenesis due to lack of those hormones. However, whether low Tco per se is related to the increased longevity of the dwarf mice remains an interesting possibility to be investigated.

Effects of cigarette smoking on lexical decision-making.

10 habitual smokers, aged 19-25 yr., were randomly assigned to smoke either a very low nicotine "Placebo" cigarette (.05-mg nicotine delivery as estimated by the FTC method) or a Nicotine cigarette (.7-mg estimated nicotine delivery). Each participant was asked to abstain from smoking for 4 to 7 hr. prior to testing. After completing a presmoking test of lexical decision-making, participants smoked either a Nicotine or Placebo cigarette and were then retested for reaction times and accuracy on the lexical decision test. When presented the most difficult lexical decisions, participants responded significantly faster after smoking a Nicotine cigarette than they did before smoking; smoking a Placebo cigarette did not affect reaction times. Response accuracy was unaffected by smoking either kind of cigarette. These results suggest that smoking a nicotine cigarette may improve attention or memory retrieval after several hours of smoking abstinence.