Bernacer J, Martinez-Valbuena I, Martinez M, Pujol N, Luis E, Ramirez-Castillo D, Pastor M A
Mind-Brain Group (Institute for Culture and Society, ICS), University of Navarra, Pamplona, Spain.
Mind-Brain Group (Institute for Culture and Society, ICS), University of Navarra, Pamplona, Spain.
Prog Brain Res. 2016;229:103-123. doi: 10.1016/bs.pbr.2016.05.003. Epub 2016 Jun 25.
One key aspect of motivation is the ability of agents to overcome excessive weighting of intrinsic subjective costs. This contribution aims to analyze the subjective cost of effort and assess its neural correlates in sedentary volunteers. We recruited a sample of 57 subjects who underwent a decision-making task using a prospective, moderate, and sustained physical effort as devaluating factor. Effort discounting followed a hyperbolic function, and individual discounting constants correlated with an indicator of sedentary lifestyle (global physical activity questionnaire; R=-0.302, P=0.033). A subsample of 24 sedentary volunteers received a functional magnetic resonance imaging scan while performing a similar effort-discounting task. BOLD signal of a cluster located in the dorsomedial prefrontal cortex correlated with the subjective value of the pair of options under consideration (Z>2.3, P<0.05; cluster corrected for multiple comparisons for the whole brain). Furthermore, effort-related discounting of reward correlated with the signal of a cluster in the ventrolateral prefrontal cortex (Z>2.3, P<0.05; small volume cluster corrected for a region of interest including the ventral prefrontal cortex and striatum). This study offers empirical data about the intrinsic subjective cost of effort and its neural correlates in sedentary individuals.
动机的一个关键方面是主体克服内在主观成本过度加权的能力。本研究旨在分析努力的主观成本，并评估其在久坐志愿者中的神经关联。我们招募了57名受试者，他们参与了一项决策任务，该任务以前瞻性、适度且持续的体力消耗作为贬值因素。努力折扣遵循双曲线函数，个体折扣常数与久坐生活方式指标（全球身体活动问卷；R = -0.302，P = 0.033）相关。24名久坐志愿者的子样本在执行类似的努力折扣任务时接受了功能磁共振成像扫描。位于背内侧前额叶皮层的一个簇的BOLD信号与所考虑的一对选项的主观价值相关（Z>2.3，P<0.05；对全脑进行多重比较校正的簇）。此外，奖励的努力相关折扣与腹外侧前额叶皮层中一个簇的信号相关（Z>2.3，P<0.05；对包括腹侧前额叶皮层和纹状体在内的感兴趣区域进行小体积簇校正）。这项研究提供了关于久坐个体中努力的内在主观成本及其神经关联的实证数据。
