Emerging Neuroscientists Seminar Series: Dr Dimokratis Karamanlis

Emerging Neuroscientists Seminar Series: Dr Dimokratis Karamanlis

This event will take place on Thursday 27 November 2025 at 13:15 (BST).

The seminar will be held at 25 Howland Street, London, W1T 4JG. This central location provides easy access for attendees.

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Talk Title: Prefrontal correlates of a social learning strategy during joint decision-making in mice

Abstract:

Social animals often observe others to guide their behavior, strategically choosing when and from whom to learn. Although frontal cortical areas represent the actions and attributes of others, how these representations adapt to varying task demands and uncertainty remains unclear. Here, we investigated how mice use the actions of conspecifics during a goal-directed task and how the medial prefrontal cortex (mPFC) implements these social computations. In our novel design, pairs of mice are separated by a transparent divider and jointly perform a visually-guided, two-alternative forced-choice task. On a trial-by-trial basis, we independently varied the visual cue contrast for each mouse to create different levels of perceptual uncertainty. We observed that mice facing low-contrast stimuli reliably copied the decisions of partners with high-contrast cues, a stereotyped behavior consistent with a “copy when uncertain” strategy. This reliance on social information was abolished when the partner was replaced by a mechanical slider, confirming the social nature of the computation. Whole-brain c-Fos mapping revealed enhanced mPFC activation in mice performing the task jointly compared to those performing it solo, suggesting this region is a hub for integrating private sensory evidence with social information. Furthermore, large-scale electrophysiological recordings from mPFC identified choice-predictive neurons whose activity differed depending on whether the mouse initiated the decision or copied its partner. Our findings demonstrate that mice actively monitor conspecifics to guide actions under perceptual uncertainty and that task demands drive a flexible representation of social actions within the mPFC.

Research Image
Maximum intensity projection of an 200-μm-deep imaging volume acquired with a light-sheet microscope. The image contains neurons in the prelimbic area of the mouse frontal cortex that were active during social decision-making.

About the speaker: Dimokratis Karamanlis

Dimos is currently a postdoctoral researcher in the lab of Sami El-Boustani at the University of Geneva. He originally studied medicine at the Aristotle University of Thessaloniki and completed his PhD on nonlinear signal processing in the retina with Tim Gollisch at the University Medical Center Göttingen. Dimos uses a combination of computational and experimental approaches to understand visual coding, how sensory signals are integrated into rapid decisions and how these signals are used to guide social learning.