Striatal pathways dissociably control action counting and goal-directed steering.

Area of Science:

• Neuroscience
• Behavioral Neuroscience
• Systems Neuroscience

Background:

• The basal ganglia (BG) play a crucial role in voluntary action control.
• Understanding the precise mechanisms by which BG organize complex behaviors is an ongoing challenge.

Purpose of the Study:

• To investigate how the basal ganglia organize complex, goal-directed actions.
• To elucidate the distinct roles of direct pathway spiny neurons (dSPNs) and indirect pathway spiny neurons (iSPNs) in action sequencing and steering.

Main Methods:

• Developed a novel operant counting task in mice to quantify continuous movement kinematics and discrete actions.
• Utilized targeted stimulation of dSPNs and iSPNs.
• Employed calcium imaging to monitor neural activity during task performance.

Main Results:

• dSPN activation steered movements contraversively and prolonged action sequences.
• iSPN activation steered movements ipsiversively and shortened action sequences.
• Neural activity in dSPNs and iSPNs reflected progress toward spatial and numerical goals, exhibiting accumulation-discharge dynamics.

Conclusions:

• The basal ganglia employ a push-pull control mechanism involving dSPNs and iSPNs.
• This system integrates movement kinematics and action counting to guide behavior towards goals.
• BG neural populations encode progress toward both spatial and numerical targets.