Abstract
Background: The smoked and smokeless forms of tobacco consist of about 4000 chemical constituents having carcinogenic potential and nicotine is the major among these. A considerable amount of evidence states that long-term administration of nicotine can change the fundamental properties of cholinergic neurotransmission, leading to changes in synaptic efficacy and resulting in modified behaviors. The effects of nicotine on cognition have been interesting, but knowledge regarding it seems to be inconsistent. As there are very few studies in India to the influence of nicotine on reaction time, especially in the case of smokeless tobacco users, this study was undertaken with an attempt to find out whether “smokeless tobacco” effects cognition by assessing the reaction time.

Aims and Objectives: To estimate and compare the auditory reaction time (ART) and visual reaction time (VRT) of tobacco users with non-tobacco users.

Materials and Methods: This study is conducted on 70 male participants with 35 healthy male tobacco chewers in the age group of 18–55 years and an equal number of healthy age-matched male controls (non-tobacco chewers). ART and VRT were recorded in both groups using a reaction time apparatus with an inbuilt chronoscope.

Results: Both ART and VRTs are faster in tobacco chewers compared to non-tobacco chewers, and the difference is statistically highly significant.

Conclusion: This study, hence, demonstrates that nicotine shortens reaction times, thereby temporarily improving cognition, which can be attributed to the stimulatory effect of nicotine that may be due to an accelerated response to the various stimuli caused by the effect of nicotine. This can be due to catecholamine release in the brain that affects the central nervous system of chronic tobacco users to have significant consequences in the near future.

Key words: Smokeless Tobacco; Nicotine; Cognition; Auditory Reaction Time; Visual Reaction Time