Every decision you make is essentially a committee act. Members chime in, options are weighed, and eventually a single proposal for action is approved by consensus. The committee, of course, is the densely knit society of neurons in your head. And “approved by consensus” is really just a delicate way of saying that the opposition was silenced.
Our brains seem to work not by generating only “correct” actions and executing them in serial, but rather by representing many possibilities in parallel, and suppressing all but one. When this inhibitory action is lost, as happens in people with frontal lobe damage, these multiple possibilities become a burden, and can lead to so-called utilization behaviors. Such impaired individuals will indiscriminately reach for objects placed in front of them - a hairbrush or a hammer, for example - and use them even in inappropriate contexts.
In essence, despite our feeling that we are singular, unified agents, we are more like hive minds unto ourselves, our brains abuzz with multiple, often conflicting plans and interests that must be managed. To Dr. Thomas Seeley, a professor of neurobiology at Cornell University, the “hive mind” is more than just a metaphor. In a recent paper in Science, Seeley and his colleagues describe a potential deep parallel between how brains and bee swarms come to a decision. With no central planner or decider, both brains and bee hives can resolve their inner differences to commit to single courses of action.
To watch a group of bees is to see a frenzy of different interests coalesce into a single, clear thought. This is analogous to neurons in the brain, which must reach a consensus on how to achieve a behavioral goal by positioning the body in space. Bees in a hive must do something similar when deciding where to move the superorganism that is the swarm. Failing to move the swarm as a single, committed unit risks splitting up the hive and losing the queen. Similarly, making a poor move could expose the hive to predators or extreme temperatures.
Like many other decision-makers, the hive’s first order of business before making a springtime move is to consider the various possibilities. Toward this end, several groups of scouts are sent off to search for a suitable new hive. When the scouts return, they each advocate for preferred new sites - often different ones - by performing the famed “waggle dance,” a figure-eight series of movements that tells other bees the direction and distance to a potential new site. These dances recruit other uncommitted bees in the hive to also advocate for the advertised site.
For a while, many scientists thought that this strategy of steadily accumulating “votes” for a particular location was sufficient to explain the hive’s eventual decision. Others, including Seeley and his colleagues, were not satisfied. What happens in cases where similarly sized groups of bees are advocating for different locations? Wouldn’t this be a formula for deadlock?
Seeley suspected that the answer had to do with a head-butting move bees make. To explore this idea, he and his team first set up swarms on an island lacking natural nests, and gave scouts a choice between two identical artificial nesting boxes. Scouts that visited one site were marked with yellow paint, while scouts visiting the other site were marked with pink paint. By tagging these two different populations, Seeley and colleagues had in a sense labeled two competing ideas, which they could then watch unfold and interact back in the collective hive mind.