Striatal dopamine release codes uncertainty in pathological gambling.

Two mechanisms of midbrain and striatal dopaminergic projections may be involved in pathological gambling: hypersensitivity to reward and sustained activation toward uncertainty. The midbrain-striatal dopamine system distinctly codes reward and uncertainty, where dopaminergic activation is a linear function of expected reward and an inverse U-shaped function of uncertainty. In this study, we investigated the dopaminergic coding of reward and uncertainty in 18 pathological gambling sufferers and 16 healthy controls.

Variable ATP yields and uncoupling of oxygen consumption in human brain.

The distribution of brain oxidative metabolism values among healthy humans is astoundingly wide for a measure that reflects normal brain function and is known to change very little with most changes of brain function. It is possible that the part of the oxygen consumption rate that is coupled to ATP turnover is the same in all healthy human brains, with different degrees of uncoupling explaining the variability of total oxygen consumption among people. To test the hypothesis that about 75% of the average total oxygen consumption of human brains is common to all individuals, we determined the variability in a large group of normal healthy adults.

Dopamine release in ventral striatum during Iowa Gambling Task performance is associated with increased excitement levels in pathological gambling.

Aims: Gambling excitement is believed to be associated with biological measures of pathological gambling. Here, we tested the hypothesis that dopamine release would be associated with increased excitement levels in Pathological Gamblers compared with Healthy Controls.

Design: Pathological Gamblers and Healthy Controls were experimentally compared in a non-gambling (baseline) and gambling condition.

Inverse association between dopaminergic neurotransmission and Iowa Gambling Task performance in pathological gamblers and healthy controls.

The dopamine system is believed to affect gambling behavior in pathological gambling. Particularly, dopamine release in the ventral striatum appears to affect decision-making in the disorder. This study investigated dopamine release in the ventral striatum in relation to gambling performance on the Iowa Gambling Task (IGT) in 16 Pathological Gamblers (PG) and 14 Healthy Controls (HC).