The recent discovery of the neurons responsible for a cockroach's motion response could lead to the discovery of how insects behave. A team of researchers from the Case Western Reserve University in Ohio hacked into the brains of 27 cockroaches.
Tiny wires were inserted to record brain activity and document motion history. The electrodes that were inserted hacked into the brain part responsible for visual and antennal inputs. These inputs are crucial in the insect's navigational activities.
The research team focused on the neuronal spike that was recorded. Using the videotaped movements of the insects, the researchers were able to match the movements with the neuronal spikes. Moreover, the team analyzed the signals for walking speed and movement directions.
"The neural activity is generated in the center of the cockroach brain. The outputs from the central complex are sent to the motor center in the thoracic ganglia — its version of the spinal cord — and on to the limbs," said Joshua Martin, who was part of the research team.
When electrical current was released into the inserted electrodes, it activated a variety of neurons which led the cockroach to repeat a movement that was previously recorded as a spontaneous action.
Biology professor Roy Ritzmann explained that the central complex seems to be a key brain area that monitors various sensory data which includes the insect's internal condition. As a result, the central complex has the capability to influence numerous movements.
Ritzmann was involved in the research along with Martin who described the central complex as a "joystick on the animal" that can be controlled for direction and speed.
Moreover, the team discovered that the central complex's coding system of neurons is quite flexible. When an insect climbs on top of an object; block its path, the neurons that are already activated in a fast-walking insect changes. This creates a new connection between locomotion and the activated neurons.
The team is looking even deeper to see how the insect's central complex shifts in order to adjust movements that will provide an animal's need. Further research could lead to the discovery of how other insect species behave.
The researchers published their findings in the Current Biology journal.
