USC College neuroscientists have traced brain circuits coursing through an area associated with food enjoyment.
The circuit tracing method allows the study of incoming and outgoing signals from any of the two brain centres.
Richard H. Thompson and Larry W. Swanson found that the circuits showed up as patterns of circular loops, suggesting that at least in this part of the rat brain, the wiring diagram looks like a distributed network.
"We started in one place and looked at the connections. It led into a very complicated series of loops and circuits. It's not an organizational chart. There's no top and bottom to it," said Swanson.
Currently, most other tracing studies focus only on one signal, in one direction, at one location.
"[We] can look at up to four links in a circuit, in the same animal at the same time. That was our technical innovation," said Swanson.
"There are usually alternate pathways through the nervous system. It's very hard to say that any one part is absolutely essential," he added.
He added that although we think that the cortex is the most important part of the brain, it's not necessarily true - it's certainly not the only part of the nervous system that determines our behaviour.
The study was published in Proceedings of the National Academy of Sciences.