Project description
Should I stay or should I go now: serotonin and the value of time
How the brain encodes the value of time to help us decide things like how much time to put into a project or whether to delay a reward is poorly understood. The neurotransmitter serotonin plays a role in suppressing impulsivity, suggesting a link. Furthermore, serotonin-releasing neurons project to the frontal cortex where there are neurons that predict the tendency to invest more time in something with a greater chance of a reward. The ERC-funded TIMEVALUE project aims to identify the serotonin-related neural mechanisms of dynamic encoding time valuation in the frontal cortex. The team will use single-cell and population recordings, chemical imaging and optogenetics to address this.
Objective
Time is our scarcest resource. Humans and other animals must decide how to spend their time, choosing from endlessly many activities with distant and uncertain outcomes, thereby assigning value to their time. The neuromodulator serotonin is thought to arbitrate between impulsivity and the patience required to wait for future rewards, suggesting a pivotal function for time valuation. Serotonin-releasing neurons project to frontal cortex, where I have previously identified neurons that predict confidence-guided time investment, but the neural and serotonergic mechanisms for time valuation remain unknown. Here, I aim to identify the cortical control mechanisms that flexibly adjust the value of time to optimize time investment decisions. My central hypothesis is that serotonin sets the value of time dynamically encoded in frontal cortex neural activity.
I will employ a family of decision tasks that allows for model-based quantification of time valuation by requiring rats to invest variable time into choice options with uncertain and delayed outcomes. We will use high-density probes and extracellular single-unit recording devices combined with chemical sensor imaging and optogenetics in freely moving rats, tools that I have developed during my postdoc, to address three main neural mechanisms: (1) What are the dynamic neural signatures of time valuation in orbitofrontal cortex, a frontal cortex area central for valuation? (2) Does serotonin specialize in conveying decision variables that construct time valuation? (3) How does serotonin impact frontal cortex neurons and network dynamics for time valuation? This research will clarify serotonin’s behavioral function and identify principles of serotonergic neuromodulation of cortical information processing. The projects will further characterize the structure of frontal cortex population dynamics underlying time valuation and decision-making.
Fields of science
Programme(s)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Topic(s)
Funding Scheme
HORIZON-ERC - HORIZON ERC GrantsHost institution
10117 Berlin
Germany