Speaker Sex Perception from Spontaneous and Volitional Nonverbal Vocalizations.

In two experiments, we explore how speaker sex recognition is affected by vocal flexibility, introduced by volitional and spontaneous vocalizations. In Experiment 1, participants judged speaker sex from two spontaneous vocalizations, laughter and crying, and volitionally produced vowels. Striking effects of speaker sex emerged: For male vocalizations, listeners' performance was significantly impaired for spontaneous vocalizations (laughter and crying) compared to a volitional baseline (repeated vowels), a pattern that was also reflected in longer reaction times for spontaneous vocalizations. Further, performance was less accurate for laughter than crying. For female vocalizations, a different pattern emerged. In Experiment 2, we largely replicated the findings of Experiment 1 using spontaneous laughter, volitional laughter and (volitional) vowels: here, performance for male vocalizations was impaired for spontaneous laughter compared to both volitional laughter and vowels, providing further evidence that differences in volitional control over vocal production may modulate our ability to accurately perceive speaker sex from vocal signals. For both experiments, acoustic analyses showed relationships between stimulus fundamental frequency (F0) and the participants' responses. The higher the F0 of a vocal signal, the more likely listeners were to perceive a vocalization as being produced by a female speaker, an effect that was more pronounced for vocalizations produced by males. We discuss the results in terms of the availability of salient acoustic cues across different vocalizations

Predictors of smoking lapse in a human laboratory paradigm

During a smoking quit attempt, a single smoking lapse is highly predictive of future relapse. While several risk factors for a smoking lapse have been identified during clinical trials, a laboratory model of lapse was until recently unavailable and, therefore, it is unclear whether these characteristics also convey risk for lapse in a laboratory environment.The primary study goal was to examine whether real-world risk factors of lapse are also predictive of smoking behavior in a laboratory model of smoking lapse.After overnight abstinence, 77 smokers completed the McKee smoking lapse task, in which they were presented with the choice of smoking or delaying in exchange for monetary reinforcement. Primary outcome measures were the latency to initiate smoking behavior and the number of cigarettes smoked during the lapse. Several baseline measures of smoking behavior, mood, and individual traits were examined as predictive factors.Craving to relieve the discomfort of withdrawal, withdrawal severity, and tension level were negatively predictive of latency to smoke. In contrast, average number of cigarettes smoked per day, withdrawal severity, level of nicotine dependence, craving for the positive effects of smoking, and craving to relieve the discomfort of withdrawal were positively predictive of number of cigarettes smoked.The results suggest that real-world risk factors for smoking lapse are also predictive of smoking behavior in a laboratory model of lapse. Future studies using the McKee lapse task should account for between subject differences in the unique factors that independently predict each outcome measure

Adolescent Brain Development and the Risk for Alcohol and Other Drug Problems

Dynamic changes in neurochemistry, fiber architecture, and tissue composition occur in the adolescent brain. The course of these maturational processes is being charted with greater specificity, owing to advances in neuroimaging and indicate grey matter volume reductions and protracted development of white matter in regions known to support complex cognition and behavior. Though fronto-subcortical circuitry development is notable during adolescence, asynchronous maturation of prefrontal and limbic systems may render youth more vulnerable to risky behaviors such as substance use. Indeed, binge-pattern alcohol consumption and comorbid marijuana use are common among adolescents, and are associated with neural consequences. This review summarizes the unique characteristics of adolescent brain development, particularly aspects that predispose individuals to reward seeking and risky choices during this phase of life, and discusses the influence of substance use on neuromaturation. Together, findings in this arena underscore the importance of refined research and programming efforts in adolescent health and interventional needs

Double target concept for smoking cessation

Tobacco use is estimated to be the largest single cause of premature death in the world. Nicotine is the major addictive substance in tobacco products. After cigarette smoking, nicotine quickly acts on its target, nicotinic acetylcholine receptors (nAChRs), which are widely distributed throughout the mammalian central nervous system and are expressed as diverse subtypes on cell bodies, dendrites and/or nerve terminals. Through the nAChRs in brain reward circuits, nicotine alters dopaminergic (DA) neuronal function in the ventral tegmental area (VTA) and increases dopamine release from VTA to nuclear accumbens (NA), which leads to nicotine reward, tolerance and dependence. After quitting smoking, smokers experience withdrawal symptoms, including depression, irritability, difficulty concentrating or sleeping, headache, and tiredness. Recently, evidence has been accumulated to reveal the molecular and cellular mechanisms of nicotine reward, tolerance and dependence. The outcomes of these investigations provide pharmacological basis for smoking cessation. Here, I briefly summarize recent advancements of our understanding of nicotine reward, tolerance and dependence. Based on these understandings, I propose a double target hypothesis, in which nAChRs and dopamine release process are two important targets for smoking cessation. Dysfunction of nAChRs (antagonism or desensitization) is crucial to abolish nicotine dependence and the maintenance of an appropriate level of extracellular dopamine eliminates nicotine withdrawal syndromes. Therefore, the medications simultaneously act on these two targets should have the desired effect for smoking cessation. I discuss how to use this double target concept to interpret recent therapies and to develop new candidate compounds for smoking cessation