How the brain turns sensation into decisions
and action

Your brain’s job is to sense the world and choose the right action, a process called perceptual decision-making. New evidence shows that these decisions may rely less on direct communication between cortical areas and more on routes that pass through the thalamus (cortico-thalamo-cortical or “transthalamic” pathways). These pathways use unusually powerful synapses to send integrated, task-relevant information to higher-order cortex (Mo et al., 2024).

Our lab studies why these pathways are so important by recording from higher-order thalamus using miniscope calcium imaging and optogenetics during perceptual decision-making. This allows us to decode how sensory information is represented and transformed into a choice to move. Understanding these circuits may offer new insight into disorders where perception and decision-making break down, such as psychosis and schizophrenia.

The predictive brain

A prominent theory of brain function proposes that every movement is accompanied by an internal “prediction” of what the senses should experience. The brain then compares predicted and actual sensations to update its model of the world, a process known as predictive coding. Although highly influential, the underlying circuit computations remain unclear.

In collaboration with computational modellers, the lab investigates which neural pathways generate and compare these predictions during tasks that tease apart self-generated movement from external sensory events. This research may help clarify why predictive processes fail in conditions like hallucinations, delusions, and movement-related disorders.

Interested students should contact christina.mo@florey.edu.au