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Jean Richard dit Bressel, P.

Publications and source records attributed to Jean Richard dit Bressel, P..

2 recordsLinked to original sources

A corticothalamic circuit trades off speed for safety during decision-making under motivational conflict

Decisions to act while pursuing goals in the presence of danger must be made quickly but safely. Premature decisions risk injury or death whereas postponing decisions risk goal loss. Here we show how mice resolve these competing demands. Using microstructural behavioral analyses, we identified the spatiotemporal dynamics of approach-avoidance decisions under motivational conflict. Then we used cognitive modelling to show that these dynamics reflect the speeded decision-making mechanisms used by humans and non-human primates, with mice trading off decision speed for safety of choice when danger loomed. Using calcium imaging and functional circuit analyses, we show that this speed-safety trade off occurs because increases in paraventricular thalamus (PVT) activity increase decision caution, thereby increasing approach-avoid decision times in the presence of danger. Our findings demonstrate that a discrete brain circuit involving the PVT and its prefrontal cortical input dynamically adjusts decision caution during motivational conflict, trading off decision speed for decision safety when danger is close. They identify the corticothalamic pathway as central to cognitive control during decision-making under conflict.

neuroscience↗

Phasic inhibition of dopamine neurons is an instrumental punisher

It is well established that the activity of VTA dopamine neurons is sufficient to serve as a Pavlovian reinforcer but whether this activity can also serve as instrumental reinforcer is less well understood. Here we studied the effects of optogenetic inhibition of VTA dopamine neurons in instrumental conditioning preparations. We show that optogenetic inhibition of VTA dopamine neurons causes a response-specific, contingency-sensitive suppression of instrumental responding. This suppression was due to instrumental response, not Pavlovian stimulus, learning and could not be attributed to deepened instrumental extinction learning. These effects of optogenetic inhibition of VTA dopamine neurons on instrumental responding are formally similar to the effects of aversive events in instrumental preparations and show that optogenetic inhibition of VTA dopamine neurons is sufficient to serve as an instrumental punisher.

neuroscience↗