Our brains may commit to social actions seconds before we are aware of choosing them, according to new research from the Hebrew University of Jerusalem. Scientists found a distinctive pattern of brain activity that reliably appears just before an animal decides to approach another individual.
The study, led by Dr. Lilah Avitan and conducted by PhD student Imri Lifshitz and colleagues at the Edmond and Lily Safra Center for Brain Sciences, suggests that social behavior emerges from a coordinated brainwide state. This pattern not only predicts if a social approach will occur, but also reflects how socially driven an individual is.
How the study tracked social choices
To examine how the brain turns social information into action, the team used zebrafish, a popular model organism in neuroscience. Zebrafish have transparent brains at early stages, allowing researchers to record activity from thousands of individual neurons in real time.
In the experiment, one zebrafish observed another freely swimming nearby, creating a simple social interaction. While the observer decided whether to swim closer, scientists monitored activity across its entire brain, capturing the sequence of events that unfolded before each social movement.
A brainwide state before movement
The researchers discovered that when a fish was about to approach another fish, its brain entered a distinctive state several seconds before it started to swim. Rather than being confined to a single region, this state involved coordinated changes across multiple brain areas.
Activity increased in the pallium, a higher-order brain region in fish that is considered analogous to parts of the mammalian cortex involved in complex decisions. At the same time, activity in other regions dropped, creating what the team describes as a neural pre-decision state for social approach.
This brainwide pattern reliably preceded social movements and allowed the scientists to predict behavior before it occurred. In effect, the brain seemed to signal that a social action was imminent well before muscles began to move.
Neural signal tied to social drive
The strength of this pre-decision pattern differed from one fish to another, and those with a stronger signal tended to show more frequent social approaches. This link suggests that the neural state does not merely trigger a single action, but reflects an underlying level of social motivation.
The findings highlight the central role of the pallium in driving social engagement, positioning it as a hub that helps transform social perception into action. According to the researchers, this region appears to integrate information and help generate the urge to move toward others.
Dr. Avitan noted that the work identifies a brainwide neural signature of social approach that emerges before movement begins and relates to an individual’s broader social tendencies. This suggests that intrinsic brain dynamics can predispose some individuals to be more social than others.
Implications for understanding human sociality
Although the experiments were done in zebrafish, key brain structures and decision-making principles are shared across many species, including humans. The results could therefore offer clues about how human brains prepare for social contact before we become consciously aware of choosing to interact.
Better understanding these preparatory brain states may ultimately inform research on conditions where social behavior is altered, such as autism spectrum conditions, social anxiety or certain psychiatric disorders. By mapping how healthy brains build up to social actions, scientists hope to identify where and how those processes can go awry.
The study adds to a growing body of work showing that decisions are preceded by measurable neural patterns that unfold over time. In the social domain, this work suggests that the brain begins organizing itself for interaction long before we say hello, smile or take a step toward someone else.
