TY - JOUR TI - Amphetamine's dose-dependent effects on dorsolateral striatum sensorimotor neuron firing DO - https://doi.org/doi:10.7282/T34748Z4 PY - 2011 AB - Dorsolateral striatum neurons were extracellularly recorded in awake behaving rats to examine amphetamine’s effects. On one hand, amphetamine has been shown to elicit motoric changes through increasing neurotransmitters such as dopamine and serotonin in the central nervous system. On the other hand, dorsolateral striatum is highly involved in motoric function and contains abundant neurotransmitter transporters that amphetamine could act upon. Therefore, it has been hypothesized that dorsolateral striatum medium spiny neurons play a role in amphetamine’s effects on motoric behavior. Although many studies have supported a role of the striatum, the involvement of its individual neurons has not been adequately characterized. Therefore, the neuronal activities of single neurons that correlate with vertical head movements in dorsolateral striatum were simultaneously recorded with head movement behavior before and after acute amphetamine injection to test the hypothesis. Behaviorally, it was observed that amphetamine induced head movements across all doses administered. Lower doses (1mg/kg and 2 mg/kg) induced more numbers of longer movements than the higher dose (4 mg/kg). Neuronally, firing of individual head movement neurons during similar head movements defined by direction, distance, duration, velocity and apex were compared before and after administration of amphetamine. Analysis revealed that the change of firing rate induced by amphetamine was co-determined by the dose administered and the baseline firing rate of the neuron. More specifically, for all doses administered, amphetamine increased the firing rate of the slower firing neurons, but decreased the firing rate of the faster firing neurons. The magnitudes of the enhancement and reduction were greater at lower doses (1mg/kg and 2 mg/kg), but were less pronounced at the high dose (4mg/kg) of amphetamine. The parallel changes of behavior and firing pattern of dorsolateral striatum neurons support the hypothesis that dorsolateral striatum neurons participate in mediating the motor behavioral effects induced by amphetamine. KW - Psychology KW - Amphetamines KW - Rats—Effect of drugs on KW - Motor neurons LA - eng ER -