Motivational processes are complex and multifaceted, with both directional and activational
aspects. Behavioral activation and exertion of effort are functions that enable organisms to …

Motivation has been defined as the process that allows organisms to regulate their internal
and external environment, and control the probability, proximity and availability of stimuli. As …

A markedly reduced interest or pleasure in activities previously considered pleasurable is a
main symptom in mood disorder and psychosis and is often present in other psychiatric …

Anhedonia is one of the core symptoms of major depressive disorder (MDD), which is often
inadequately treated by traditional antidepressants. The modern framework of anhedonia …

It has been known for some time that nucleus accumbens dopamine (DA) is involved in
aspects of motivation, but theoretical approaches to understanding the functions of DA have …

Operant behavior is not only regulated by factors related to the quality or quantity of
reinforcement, but also by the work requirements inherent in performing instrumental …

Brain-derived neurotrophic factor (BDNF) is widely accepted as being critical for neural and
synaptic plasticity throughout the nervous system. Recent work has shown that BDNF in the …

Major depressive disorder is one of the most common and debilitating psychiatric disorders.
Some of the motivational symptoms of depression, such anergia (lack of self-reported …

Exposure to stress has profound, but complex, actions on motivated behavior and decision-
making. These effects are central to core symptoms of a number of psychiatric disorders that …

Effort-based decision making is studied using tasks that offer choices between high-effort
options leading to more highly valued reinforcers versus low-effort/low-reward options …