Motohiro Nakajima

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Repeated exposures to psychological stress can lead to or worsen diseases of slow accumulation such as heart diseases and cancer. The main challenge in addressing the growing epidemic of stress is a lack of robust methods to measure a person's exposure to stress in the natural environment. Periodic self-reports collect only subjective aspects, often miss(More)
The current study examined whether prequit trait negative mood and smoking motives have different predictive patterns of smoking relapse in men and women. Thirty-three female (mean age±SEM: 34.9±2.5) and 38 male (mean age±SEM: 37.1±2.3) smokers interested in smoking cessation completed forms on smoking history, negative mood (i.e., depression, anxiety, and(More)
Chronic smoking has been linked with alterations in endogenous pain regulation. These alterations may be pronounced when individuals quit smoking because nicotine withdrawal produces a variety of psychological and physiological symptoms. Smokers interested in quitting (n = 98) and nonsmokers (n = 37) completed a laboratory session including cold pressor(More)
Alterations in the stress response and endogenous pain regulation mechanisms may contribute directly and indirectly to maintenance of nicotine dependence and relapse. We examined the extent to which nicotine dependence alters endogenous pain regulatory systems, including the hypothalamic-pituitary-adrenocortical axis, cardiovascular activity, and(More)
A typical oxidative DNA damage, 8-hydroxydeoxyguanosine (8-OHdG), was evaluated in human polymorphonuclear leukocytes (PMN) and mononuclear leukocytes (MN) by an anaerobic determination method. The mean 8-OHdG values were the lowest level ever reported [PMN, 3.07 +/- 1.45; MN, 2.37 +/- 1.21 8-OHdG/10(6) deoxyguanosine molecules (dG); n = 92]. According to a(More)
Recent research suggests a role for the appetite hormone leptin in cigarette smoking. This study examined patterns of change in leptin in response to stress and associations with craving during the initial phase of a quit attempt. Thirty-six smokers (average age±SEM, 33.4±2.4) interested in smoking cessation set a quit day and were required to be abstinent(More)
This study examined the effects of stress on taste perception. Participants (N = 38; 21 women) completed two laboratory sessions: one stress (public speaking, math, and cold pressor) and one control rest session. The taste perception test was conducted at the end of each session and included rating the intensity and pleasantness of sweet, salty, sour, and(More)
Recent advances in mobile health have produced several new models for inferring stress from wearable sensors. But, the lack of a gold standard is a major hurdle in making clinical use of continuous stress measurements derived from wearable sensors. In this paper, we present a stress model (called <i>cStress</i>) that has been carefully developed with(More)
Recent preclinical evidence suggests that leptin may modulate the stress response and may increase nociception. In this study, we examined for the first time the extent to which cigarette smoking is associated with leptin levels during an extended rest period and in response to noxious stimuli. Repeated blood samples were collected during a laboratory(More)
Craving usually precedes a lapse for impulsive behaviors such as overeating, drinking, smoking, and drug use. Passive estimation of craving from sensor data in the natural environment can be used to assist users in coping with craving. In this paper, we take the first steps towards developing a computational model to estimate cigarette craving (during(More)