Search NEL Online

Journal Article 2014; 35(7): 594-601 PubMed PMID: 25617882 Citation  Keywords:  Adolescent, Choice Behavior, Dominance-Subordination, Europe, Female, Humans, Male, Masochism:psychology, Reproduction, Sadism:psychology, Sexual Behavior:psychology, Sexual Partners:psychology, Surveys and Questionnaires, Urban Population, Young Adult,.   

OBJECTIVES: Equality between partners is considering a feature of the functional partnerships in westernized societies. However, the evolutionary consequences of how in-pair hierarchy influences reproduction are less known. Attraction of some high-ranking women towards low-ranking men represents a puzzle.

METHODS: Young urban adults (120 men, 171 women) filled out a questionnaire focused on their sexual preference for higher or lower ranking partners, their future in-pair hierarchy, and hierarchy between their parents.

RESULTS: Human pairs with a hierarchic disparity between partners conceive more offspring than pairs of equally-ranking individuals, who, in turn, conceive more offspring than pairs of two dominating partners. Importantly, the higher reproductive success of hierarchically disparate pairs holds, regardless of which sex, male or female, is the dominant one. In addition, the subjects preferring hierarchy disparity in partnerships were with greater probability sexually aroused by such disparity, suggesting that both the partnership preference and the triggers of sexual arousal may reflect a mating strategy.

CONCLUSION: These results challenge the frequently held belief in within-pair equality as a trademark of functional partnerships. It rather appears that existence of some disparity improves within-pair cohesion, facilitating both cooperation between partners and improving the pairs' ability to face societal challenges. The parallel existence of submissivity-dominance hierarchies within human sexes allows for the parallel existence of alternative reproductive strategies, and may form a background for the diversity of mating systems observed in human societies. Arousal of overemphasized dominance/submissiveness may explain sadomasochistic sex, still little understood from the evolutionary psychology point of view....

Read abstract  Full text PDF

Journal Article 2014; 35(6): 510-517 PubMed PMID: 25433845 Citation  Keywords:  Adolescent, Adult, Antisocial Personality Disorder:diagnosis, Choice Behavior, Female, Gambling:psychology, Games, Experimental, Humans, Impulsive Behavior, Male, Models, Psychological, Predictive Value of Tests, Probability, Risk-Taking, Young Adult,.   

BACKGROUND: This study investigated the relationships between psychopathy and impulsive and risky decision making, by utilizing intertemporal and probabilistic choices for both gain and loss, in addition to the Iowa gambling task.

METHODS: The Psychopathic Personality Inventory-Revised - a 154-item measure that assesses psychopathic traits by self-report - was used with a 4-point response scale to assess 113 undergraduate students from three Japanese universities. Participants' performance on the Iowa Gambling Task and four behavioral neuroeconomic tasks of discounting - delayed gain, delayed loss, uncertain gain, and uncertain loss - were estimated.

RESULTS: Risky decisions in probability discounting of gain and loss were associated with psychopathy. Psychopathic traits had no relationship with performance on the Iowa Gambling and were not significantly related to delay discounting.

CONCLUSIONS: Psychopathy is predicted by risky decision in probability discounting of gain and loss, but not strongly associated with future myopia. Implications of the present findings for neuroeconomics and neurolaw are discussed....

Read abstract  Full text PDF

Journal Article 2012; 33(7): 709-712 PubMed PMID: 23391882 Citation  Keywords:  Analgesics, Opioid:pharmacology, Animals, Behavior, Animal:drug effects, Choice Behavior:drug effects, Conditioning (Psychology):drug effects, Male, Mice, Morphine:pharmacology, Morphine Dependence:physiopathology, Music, Nucleus Accumbens:drug effects, R.   

OBJECTIVES: This research aims at studying the neuroendocrine effects of music on creating morphine dependence in mice using conditioned place preference (CPP).

METHODS: The mice treated with 10 mg/kg morphine subcutaneously, fast music and slow music. Morphine was used to create dependence. In order to recognize the morphine rewarding effects, CPP technique was used. In the conditioning stage that lasted for 8 days, different groups of mice, after receiving the treatment were randomly placed in compartment for 30 minutes. The post-conditioning stage included the fourth day, the ninth day, the 12th day and the 16th day.

RESULTS: Comparing place preference between morphine group and the control group, a significant increase (p<0.05) was observed in the place preference of morphine group, while a significant decrease (p<0.05) was demonstrated in the place preferences of morphine + taxi girl music group compared with morphine group alone. In addition morphine + alone in the rain music group demonstrated a significantly increased conditioned place preference (p<0.05) compared with the morphine group.

CONCLUSIONS: Alone in the rain music acts as a positive pleasant emotion increasing the dopaminergic activity in the Nucleus Accumbens (NAc) and Ventral Tegmental Area (VTA) and through associated learning mechanisms of reward-related behavior increases morphine addiction. However, taxi girl music may act as unpleasant experiences producing negative emotions and reducing morphine addiction....

Read abstract  Full text PDF

Journal Article 2011; 32(4): 400-404 PubMed PMID: 21876494 Citation  Keywords:  Brain Chemistry:physiology, Choice Behavior:physiology, Humans, Mental Disorders:physiopathology, Models, Psychological, Suicide:psychology,.   

: Suicidal behavior is a leading cause of injury and death worldwide. Suicide has been associated with psychiatric illnesses such as depression and schizophrenia, as well as economic uncertainty, and social/cultural factors. This study proposes a neuroeconomic framework of suicide. Neuroeconomic parameters (e.g., risk-attitude, probability weighting, time discounting in intertemporal choice, and loss aversion) are predicted to be related to suicidal behavior. Neurobiological and neuroendocrinological substrates such as serotonin, dopamine, cortisol (HPA axis), nitric oxide, serum cholesterol, epinephrine, norepinephrine, gonadal hormones (e.g., estradiol and progesterone), dehydroepiandrosterone (DHEA) in brain regiouns such as the orbitofrontal/dorsolateral prefrontal cortex and limbic regions (e.g., the amygdala) may supposedly be related to the neuroeconomic parameters modulating the risk of suicide. The present framework puts foundations for "molecular neuroeconomics" of decision-making processes underlying suicidal behavior....

Read abstract  Full text PDF

Journal Article 2011; 32(3): 221-225 PubMed PMID: 21712792 Citation  Keywords:  Adolescent, Algorithms, Behavior, Addictive:psychology, Choice Behavior, Economics, Humans, Nonlinear Dynamics, Psychophysics, Time Perception:physiology,.   

: Neuroeconomic conditions for "rational addiction" (Becker & Murphy 1988) have been unknown. This paper derived the conditions for "rational addiction" by utilizing a nonlinear time-perception theory of "hyperbolic" discounting, which is mathematically equivalent to the q-exponential intertemporal choice model based on Tsallis' statistics. It is shown that (i) Arrow-Pratt measure for temporal cognition corresponds to the degree of irrationality (i.e., Prelec's "decreasing impatience" parameter of temporal discounting) and (ii) rationality in addicts is controlled by a nondimensionalization parameter of the logarithmic time-perception function. Furthermore, the present theory illustrates the possibility that addictive drugs increase impulsivity via dopaminergic neuroadaptation without increasing irrationality. Future directions in the application of the model to studies in neuroeconomics are discussed....

Read abstract  Full text PDF

Comparative Study 2010; 31(5): 616-621 PubMed PMID: 21178944 Citation  Keywords:  Adult, Aged, Choice Behavior, Corticosterone:secretion, Female, Follow-Up Studies, Humans, Hydrocortisone:secretion, Impulsive Behavior:metabolism, Individuality, Male, Mass Spectrometry, Middle Aged, Models, Psychological, Reward, Saliva:metabolism, Sex .   

OBJECTIVES: Stress hormones have been associated with temporal discounting. Although time-discount rate is shown to be stable over a long term, no study to date examines whether individual differences in stress hormones could predict individuals' time-discount rates in the relatively distant future (e.g., six month later), which is of interest in neuroeconomics of stress-addiction association.

METHODS: We assessed 87 participants' salivary stress hormone (cortisol, cortisone, and alpha-amylase) levels and hyperbolic discounting of delayed rewards consisting of three magnitudes, at the time-interval of six months. For salivary steroid assays, we employed a liquid chromatography/ mass spectroscopy (LC/MS) method. The correlations between the stress hormone levels and time-discount rates were examined.

RESULTS: We observed that salivary alpha-amylase (sAA) levels were negatively associated with time-discount rates in never-smokers. Notably, salivary levels of stress steroids (i.e., cortisol and cortisone) negatively and positively related to time-discount rates in men and women, respectively, in never-smokers. Ever-smokers' discount rates were not predicted from these stress hormone levels.

CONCLUSIONS: Individual differences in stress hormone levels predict impulsivity in temporal discounting in the future. There are sex differences in the effect of stress steroids on temporal discounting; while there was no sex defference in the relationship between sAA and temporal discounting....

Read abstract  Full text PDF

Journal Article 2009; 30(5): 643-646 PubMed PMID: 20035253 Citation  Keywords:  Adolescent, Choice Behavior:physiology, Decision Making:physiology, Emotions:physiology, Female, Games, Experimental, Humans, Neuropsychological Tests, Saliva:enzymology, Salivary alpha-Amylases:metabolism, Young Adult,.   

OBJECTIVES: This study aimed to examine the role of emotions in rejection of unfair offers in an ultimatum game, which is of interest in neuroeconomics of fairness.

METHODS: Thirty-seven participants played a one-shot ultimatum game as responders and decided whether to accept or reject the unfair offers by the proposers. Salivary alpha-amylase (sAA) was assessed before and after the ultimatum game.

RESULTS: Forty-four percent of the participants rejected the unfair offers. While sAA levels of the participants who rejected the unfair offers increased between pre- and post-experiment, sAA levels of the participants who accepted the unfair offers remain unchanged.

CONCLUSIONS: Emotional stress response was observed when participants rejected the unfair offers. Our results indicated that rejection of the unfair offers is a reflection of emotional arousal associated with adrenergic activations....

Read abstract  Full text PDF

Journal Article 2009; 30(2): 185-191 PubMed PMID: 19675524 Citation  Keywords:  Attention, Choice Behavior, Culture, Economics, Humans, Models, Neurological, Reinforcement (Psychology), Time Factors,.   

: According to theories of cultural neuroscience, Westerners and Easterners may have distinct styles of cognition (e.g., different allocation of attention). Previous research has shown that Westerners and Easterners tend to utilize analytical and holistic cognitive styles, respectively. On the other hand, little is known regarding the cultural differences in neuroeconomic behavior. For instance, economic decisions may be affected by cultural differences in neurocomputational processing underlying attention; however, this area of neuroeconomics has been largely understudied. In the present paper, we attempt to bridge this gap by considering the links between the theory of cultural neuroscience and neuroeconomic theory of the role of attention in intertemporal choice. We predict that (i) Westerners are more impulsive and inconsistent in intertemporal choice in comparison to Easterners, and (ii) Westerners more steeply discount delayed monetary losses than Easterners. We examine these predictions by utilizing a novel temporal discounting model based on Tsallis' statistics (i.e. a q-exponential model). Our preliminary analysis of temporal discounting of gains and losses by Americans and Japanese confirmed the predictions from the cultural neuroeconomic theory. Future study directions, employing computational modeling via neural networks, are outlined and discussed....

Read abstract  Full text PDF