The Behavioral Economics of Smoking

Evidence that economic principles may be employed to predict the rates at which cigarettes are consumed is presented from several laboratory experiments. In these experiments, cigarette-deprived smokers were required to make a effortful response to earn cigarette puffs. Changing the number of responses required per puff is conceptualized as a price manipulation. Our experiments show that these price increases decrease cigarette consumption and that price elasticity of demand increases with increases in price. When from 74 different smokers, participating in 17 different experiments, in our laboratory were analyzed, five demographic variables were related to rates of earning and smoking cigarettes in the lab: 1) males smoked more than females; 2) less-educated individuals tended to smoke more than better-educated smokers; 3) higher rates of smoking were observed in individuals with high Fagerstr”m smoke more than heavy drinkers; and 5) unemployed subjects smoked more than employed individuals. Demographic effects on price elasticity did not accord as well with econometric data. Finally, we discuss the ability of behavioral- economic laboratory experiments to model cigarette smoking in the natural economy, and the validity of using these laboratory results as a means of assessing the likely effects of public-policy initiatives. The results from one such experiment are presented that suggest the economic concept of inferior goods may be informative in understanding nicotine-replacement products and the likely effects of differential pricing of cigarettes and these replacement products.

Alcohol-Dependent Individuals Discount Sex at Higher Rates than Controls

Background Research on delay discounting has expanded our understanding of substance dependence in many ways. Recently, orderly discounting of sexual rewards has been demonstrated in both substance-dependent individuals, and healthy controls. Less clear, however, is if rates of sexual discounting are higher than controls in alcohol-dependent-individuals. Methods 20 Alcohol-dependent individuals and 21 healthy control participants completed two delay-discounting tasks. One task involved monetary rewards, whereas the other involved the discounting of sexual rewards (i.e., number of sex acts). Results Alcohol dependent individuals discounted sexual rewards at significantly higher rates than did controls. There was a trend towards, but not a similarly significant relation for the discounting of monetary rewards. Conclusions Rates of sexual discounting are elevated in alcohol dependent individuals. If this relation is replicated in other at risk populations, the rapid devaluation of sexual rewards may be a behavioral marker of impulsive sexual choices

Stuck in Time: Negative Income Shock Constricts the Temporal Window of Valuation Spanning the Future and the Past

Insufficient resources are associated with negative consequences including decreased valuation of future reinforcers. To determine if these effects result from scarcity, we examined the consequences of acute, abrupt changes in resource availability on delay discounting-the subjective devaluation of rewards as delay to receipt increases. In the current study, 599 individuals recruited from Amazon Mechanical Turk read a narrative of a sudden change (positive, neutral, or negative) to one\u27s hypothetical future income and completed a delay discounting task examining future and past monetary gains and losses. The effects of the explicit zero procedure, a framing manipulation, was also examined. Negative income shock significantly increased discounting rates for gains and loses occurring both in the future and the past. Positive income windfalls significantly decreased discounting to a lesser extent. The framing procedure significantly reduced discounting under all conditions. Negative income shocks may result in short-term choices

Variable-frequency-train stimulation of skeletal muscle after spinal cord injury

Skeletal muscle, after spinal cord injury (SCI), becomes highly susceptible to fatigue. Variable-frequency trains (VFTs) enhance force in fatigued human skeletal muscle of able-bodied (AB) individuals. VFTs do this by taking advantage of the catch-like property of skeletal muscle. However, mechanisms responsible for fatigue in AB and SCI subjects may not be the same, and the efficacy of VFT stimulation after SCI is unknown. Accordingly, we tested the hypothesis that VFT stimulation would augment torque-time integral in SCI subjects. The quadriceps femoris muscle was stimulated with constant frequency trains (CFTs) (six 200 s square wave pulses separated by 70 ms) or VFTs (a train identical to the CFT, except that the first two pulses were separated by 5 ms) in SCI and AB subjects. After 180 contractions (50% duty cycle), isometric peak torque decreased 44, 56, and 67 percent, in the AB (n = 10), acute SCI (n = 10), and chronic SCI (n = 12) groups, respectively. In fatigued muscle, VFTs enhanced the torque-time integral by 18 percent in AB subjects and 6 percent in chronic SCI patients, and had no effect in acute SCI patients when compared to the corresponding CFT. The much faster rise times in SCI subjects (~80 ms vs. 120 ms in AB subjects) probably contributed to the inability of VFTs to enhance torque-time integrals in SCI patients. The results suggest that the use of VFT stimulation in patients with SCI may not be as efficacious as it is in AB persons