Acute effects of nicotine on visual search tasks in young adult smokers.
BACKGROUND
Nicotine is known to improve performance on tests involving sustained attention and recent research suggests that nicotine may also improve performance on tests involving the strategic allocation of attention and working memory.


OBJECTIVE
We used measures of accuracy and response latency combined with eye-tracking techniques to examine the effects of nicotine on visual search tasks.


METHODS
In experiment 1 smokers and non-smokers performed pop-out and serial search tasks. In experiment 2, we used a within-subject design and a more demanding search task for multiple targets. In both studies, 2-h abstinent smokers were asked to smoke one of their own cigarettes between baseline and tests.


RESULTS
In experiment 1, pop-out search times were faster after nicotine, without a loss in accuracy. Similar effects were observed for serial searches, but these were significant only at a trend level. In experiment 2, nicotine facilitated a strategic change in eye movements resulting in a higher proportion of fixations on target letters. If the cigarette was smoked on the first trial (when the task was novel), nicotine additionally reduced the total number of fixations and re-fixations on all letters in the display.


CONCLUSIONS
Nicotine improves visual search performance by speeding up search time and enabling a better focus of attention on task relevant items. This appears to reflect more efficient inhibition of eye movements towards task irrelevant stimuli, and better active maintenance of task goals. When the task is novel, and therefore more difficult, nicotine lessens the need to re-fixate previously seen letters, suggesting an improvement in working memory.
Rycroft
Nicola
N
Department of Psychology, University of Sussex, Falmer, Brighton BN1 9QH, UK.
Rusted
Jennifer M
JM
Hutton
Samuel B
SB
D000328:Adult; D000367:Age Factors; D005731:Ganglionic Stimulants / Q000494:pharmacology; D006801:Humans; D008297:Male; D009538:Nicotine / Q000494:pharmacology*; D010364:Pattern Recognition, Visual / Q000187:drug effects; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D012438:Saccades / Q000187:drug effects / Q000502:physiology; D012907:Smoking; D013647:Task Performance and Analysis; D014796:Visual Perception / Q000187:drug effects*
D005731:Ganglionic Stimulants; D009538:Nicotine