This investigation deals with the influence of situational variables and individual differences (internal versus external locus of control and achievement motivation) on self-imposed gratification delay. The sample consisted of 243 male and female high school students. Subjects who only had to wait for the delayed reward (Group 1) chose the delayed reward significantly more frequently than subj...

Sensitivity to time, including the time of reward, guides the behaviour of all organisms. Recent research suggests that all major reward structures of the brain process the time of reward occurrence, including midbrain dopamine neurons, striatum, frontal cortex and amygdala. Neuronal reward responses in dopamine neurons, striatum and frontal cortex show temporal discounting of reward value. The...

Return on investment is a driving force that motivates and is a reward for investors. Investment returns are important for investors, in order for the entire investment game to be realized. Evaluating efficiency is the only logical way (Before risk assessment) that investors can do to compare alternative and different investments. Measuring real returns (relative to the past) is needed to bette...

Depression is a debilitating condition with a high prevalence, but aetiology and pathophysiology are still unclear. Various reward-learning paradigms have been used to show impairments in depression. Both trait pessimism and neuroticism are associated with depression, but their link with the impairments in reward learning and decision-making have not been investigated. A Pavlovian conditioning ...

The globus pallidus (internal segment, GPi) is traditionally regarded as part of the motor system. In this issue of Neuron, Hong and Hikosaka report on a little known projection from the monkey GPi to the lateral habenula that is modulated by reward. This adds an important branch to the brain's reward circuitry.

Multivariate reward processes with reward functions of constant rates, defined on a semi-Markov process, first were studied by Masuda and Sumita, 1991. Reward processes with nonlinear reward functions were introduced in Soltani, 1996. In this work we study a multivariate process , , where are reward processes with nonlinear reward functions respectively. The Laplace transform of the covar...