Behavioural testing equipment for investigating the role of phasic dopamine signaling in cognitive flexibility

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The ability to use information flexibly and execute appropriate adaptive behaviours in response to changing environmental conditions is essential for survival in all species, and our previous work has shown the brain chemical dopamine plays a crucial role in these processes. Disruptions in dopamine signaling with certain drugs impedes different forms of cognitive flexibility, including shifting between different behavioural strategies and decision making about different choices associated with different risks and rewards. The contribution of dopamine to these processes is thought to be mediated in part by brief, "phasic" increases and decreases in the activity of midbrain dopamine neurons that signal rewarded and non-rewarded events. However, the specific role that phasic dopamine activity plays in these forms of behavioural flexibility cannot be ascertained with standard pharmacological approaches. To address this issue directly, the present proposal is requesting specialized behavioural testing equipment that will enable us to deliver discrete bursts of electrical stimulation to dopamine neurons or inhibitory inputs to this region, to mimic the way these neurons behave when animals receive reward, or do not receive an expected reward. In essence, we hope that by activating or inhibiting dopamine neurons in a temporally specific manner we can mimic these phasic events to ascertain their control over behaviour, essentially tricking the brain into encoding a rewarded or non-rewarded events, leading to alterations in behaviour. The requested equipment is essential for us to employ this approach, enabling us to provide the first direct experimental data regarding the function of phasic dopamine signaling. This information will provide crucial insight into how a fundamental form of dopamine communication contributes to different aspects of reward-related learning and modification of learned behaviours in response to changes in reward contingencies.