Nucleus Accumbens and Reward Circuits Flashcards
What two nuclei define the ventral straitum?
The nucleus accumbens and the olfactory tubercle.
What basal ganglion circuit includes the nucleus accumbens?
The limbic circuit.
What neurons connect the striatum to the globus pallidus and the substantia nigra pars reticulata?
Medium spiny neurons (inhibitory GABAnergic)
What are the components of the basal ganglia limbic circuit that select emotional responses to be executed (direct pathway)?
Cortical input, ventral striatum, and the mediodorsal nucleus (in thalamus).
What are the cortical circuits of the limbic circuit?
The anterior cingulate, prefrontal cortex, and orbital frontal cortex.
What are the components of the basal ganglia circuits that produce inhibitory surround for the selected response sequence (indirect pathway)?
Cerebral cortex, striatum (caudate/putamen), external globus pallidus, and the subthalamic nucleus.
What neurotransmitter is released by the subthalamic nucleus?
It releases glutamate (excitatory) to the internal globus pallidus.
What is the midbrain nucleus that projects dopaminergic axons to the nucleus accumbens to adjust the intensity of emotional responses based upon expectations of reward?
The ventral tegmental area (VTA).
What dopaminergic receptor on medium spiny neurons enhances the direct limbic pathway?
D1 receptors.
What is the midbrain nucleus that mediates lateral habenular inhibitory effects upon the VTA?
The rostromedial tegmental nucleus (RMTg). (the lateral habenular nuclei inhibit the VTA via the RMTg).
What neurotransmitter do RMTg neurons release upon dopaminergic VTA neurons?
GABA (inhibit the VTA).
