Implicit AZD6738 order timing emerges from observed temporal regularities in a changing stimulus without any voluntary estimate of elapsed time, unlike explicit
The neural bases of explicit and implicit timing are likely different. It has been shown that the basal ganglia (BG) play a central role in explicit timing. In order to determine the influence of BG in implicit timing, we investigated the influence of early Parkinson’s disease (PD) and aging on the latency of anticipatory eye movements. We hypothesized that a deficit of implicit timing should yield inadequate temporal expectations, and consequently abnormally timed anticipatory eye movements compared with age-matched controls. To test this hypothesis, we used an oculomotor paradigm where anticipation of a salient target event plays a central role. Participants pursued a visual target that moved along a circular path at a constant velocity. After a randomly short (1200 ms) or long (2400 ms) forward path, the
target reversed direction, returned to its starting position and stopped.
Target motion reversal caused an abrupt ‘slip’ of the pursued target image on the retina and was a particularly salient event evoking anticipatory eye movements. Anticipatory eye movements were less frequent in PD patients. However, the timing of anticipation of target motion reversal was statistically similar in DNA/RNA Synthesis inhibitor PD patients and control subjects. Other eye movements showed BTSA1 molecular weight statistically significant differences between PD and controls, but these differences could be attributed to other factors.
We conclude that all anticipatory eye movements are not similarly impaired in PD and that implicit timing of salient events seems largely unaffected by this disease. The results support the hypothesis that implicit and explicit
timing are differently affected by BG dysfunction. (C) 2012 Elsevier Ltd. All rights reserved.”
“Projections from neurons of the bed nucleus of the stria terminalis (BST) to the ventral tegmental area (VTA) are crucial to behaviors related to reward and motivation. Over the past few years, we have undertaken a series of studies to understand: 1) how excitatory inputs regulate in vivo excitable properties of BST neurons, and 2) how BST inputs in turn modulate neuronal activity of dopamine neurons in VTA. Using in vivo extracellular recording techniques in anesthetized rats and tract-tracing approaches, we have demonstrated that inputs from the infralimbic cortex and the ventral subiculum exert a strong excitatory influence on BST neurons projecting to the VIA. Thus, the BST is uniquely positioned to receive emotional and learning-associated informations and to integrate these into the reward/motivation circuitry. We will discuss how changes in the activity of BST neurons projecting to the VIA could participate in the development or exacerbation of psychiatric conditions such as drug addiction. (C) 2009 Elsevier Inc. All rights reserved.