Substantial decline of phasic dopamine signaling in senescent male rats does not impact dopamine-dependent Pavlovian conditioning.

Normal aging is associated with cognitive decline which impacts financial decision making. One of the underlying features of decision making is probability estimation, in which nucleus accumbens dopamine signaling has been implicated. Here we used fast-scan cyclic voltammetry to probe for age differences in dopamine signaling, and pharmacological manipulation to test for age differences in the dopamine dependence of Pavlovian conditioning.

Cocaine Seeking And Taking Are Oppositely Regulated By Dopamine.

In some individuals, drug-associated cues subsume potent control of behavior, such as the elicitation of drug craving and automatized drug use. The intensity of this cue reactivity is highly predictive of relapse and other clinical outcomes in substance use disorders. It has been postulated that this cue reactivity is driven by augmentation of dopamine release over the course of chronic drug use.

Implantable Aptamer-Graphene Microtransistors for Real-Time Monitoring of Neurochemical Release in Vivo.

The real-time monitoring of neurochemical release plays a critical role in understanding the biochemical process of the complex nervous system. Current technologies for such applications, including microdialysis and fast-scan cyclic voltammetry, suffer from limited spatiotemporal resolution or poor selectivity. Here, we report a soft implantable aptamer-graphene microtransistor probe for real-time monitoring of neurochemical release.

Catecholaminergic Innervation of the Lateral Nucleus of the Cerebellum Modulates Cognitive Behaviors.

The cerebellum processes neural signals related to rewarding and aversive stimuli, suggesting that the cerebellum supports nonmotor functions in cognitive and emotional domains. Catecholamines are a class of neuromodulatory neurotransmitters well known for encoding such salient stimuli. Catecholaminergic modulation of classical cerebellar functions have been demonstrated.

Hitchhiker's Guide to Voltammetry: Acute and Chronic Electrodes for in Vivo Fast-Scan Cyclic Voltammetry.

Fast-scan cyclic voltammetry (FSCV) has been used for over 20 years to study rapid neurotransmission in awake and behaving animals. These experiments were first carried out with carbon-fiber microelectrodes (CFMs) encased in borosilicate glass, which can be inserted into the brain through micromanipulators and guide cannulas. More recently, chronically implantable CFMs constructed with small diameter fused-silica have been introduced.

Prolonged dopamine signalling in striatum signals proximity and value of distant rewards.

Predictions about future rewarding events have a powerful influence on behaviour. The phasic spike activity of dopamine-containing neurons, and corresponding dopamine transients in the striatum, are thought to underlie these predictions, encoding positive and negative reward prediction errors. However, many behaviours are directed towards distant goals, for which transient signals may fail to provide sustained drive.

Sub-second dopamine detection in human striatum.

Fast-scan cyclic voltammetry at carbon fiber microelectrodes allows rapid (sub-second) measurements of dopamine release in behaving animals. Herein, we report the modification of existing technology and demonstrate the feasibility of making sub-second measurements of dopamine release in the caudate nucleus of a human subject during brain surgery. First, we describe the modification of our electrodes that allow for measurements to be made in a human brain.

Chronic microsensors for longitudinal, subsecond dopamine detection in behaving animals.

Neurotransmission operates on a millisecond timescale but is changed by normal experience or neuropathology over days to months. Despite the importance of long-term neurotransmitter dynamics, no technique exists to track these changes in a subject from day to day over extended periods of time. Here we describe and characterize a microsensor that can detect the neurotransmitter dopamine with subsecond temporal resolution over months in vivo in rats and mice.

Wireless transmission of fast-scan cyclic voltammetry at a carbon-fiber microelectrode: proof of principle.

Fast-scan cyclic voltammetry (FSCV) at a carbon-fiber microelectrode (CFM) provides exquisite temporal and spatial resolution for monitoring brain chemistry. The utility of this approach has recently been demonstrated by measuring sub-second dopamine changes associated with behavior. However, one drawback is the cable link between animal and recording equipment that restricts behavior and precludes monitoring in complex environments.