Disruption of Nrxn1α within excitatory forebrain circuits drives value-based dysfunction

Area of Science:

• Neuroscience
• Genetics
• Behavioral Science

Background:

• Goal-directed behaviors are crucial for normal functioning but are impaired in neuropsychiatric disorders.
• The molecular underpinnings of goal-directed dysfunction in these disorders are not well understood.
• Neurexin1α (Nrxn1α) is a synaptic molecule associated with neuropsychiatric diseases.

Purpose of the Study:

• To investigate the role of Neurexin1α (Nrxn1α) in value-based decision-making.
• To determine the brain regions and cell types where Nrxn1α disruption leads to goal-directed behavior deficits.

Main Methods:

• Examined mice with constitutive and brain region-specific Nrxn1α mutations.
• Utilized value-based choice paradigms and reinforcement learning modeling.
• Analyzed neural signals in the striatum.

Main Results:

• Nrxn1α knockouts showed reduced selection of beneficial outcomes and impaired avoidance of costly options.
• Reinforcement modeling indicated deficits in value updating and representation.
• Selective disruption of Nrxn1α in telencephalic excitatory neurons, but not thalamic neurons, replicated these choice abnormalities.
• Forebrain Nrxn1α knockout perturbed value-modulated neural signals in the striatum.

Conclusions:

• Region-specific disruption of Nrxn1α in forebrain excitatory neurons underlies value-based decision-making deficits.
• These findings reveal potential neural substrates for cognitive dysfunction in neuropsychiatric diseases.
• Nrxn1α plays a critical role in the neural circuits governing goal-directed behavior and value representation.