A hypothalamic-thalamostriatal circuit that controls approach-avoidance conflict in rats

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Neurobiology

Background:

• Survival necessitates balancing reward-seeking and threat-avoidance behaviors.
• The neural underpinnings of this motivational conflict are not well understood.

Purpose of the Study:

• To identify and characterize neural circuits regulating the conflict between seeking rewards and avoiding threats.
• To elucidate the role of anterior paraventricular thalamus (aPVT) neurons in this conflict.

Main Methods:

• Utilized an approach-food versus avoid-predator threat conflict test in a rat model.
• Employed neuronal inactivation and activation techniques to study aPVT^CRF neuron function.
• Investigated neural projections using pathway tracing and assessed behavioral responses.

Main Results:

• Identified a subpopulation of corticotrophin-releasing factor (CRF)-expressing neurons in the anterior paraventricular thalamic nucleus (aPVT) activated during conflict.
• Inactivating aPVT^CRF neurons shifted behavior towards food seeking, while activation suppressed food seeking.
• Discovered a hypothalamic-VMH to aPVT pathway mediating defensive behaviors specifically during conflict.

Conclusions:

• Described a novel hypothalamic-thalamostriatal circuit involving aPVT^CRF neurons and their projections to the nucleus accumbens (NAc).
• This circuit plays a crucial role in suppressing reward-seeking behavior when faced with competing threat avoidance demands.