A Stanford research team, including neuroscientists Shruti Siva, Sadak Nam and Toshio Kawada, has found evidence that hippocampus and neocortex are separated by a single lepton-interacting protein called Bubble-1. The researchers reported that the memory, learning and behavior deficits exhibited by a mouse population with an intact Bubble-1 gene expression were no longer present when the mice began to express it. The study was published in Neuron.
“On the one hand, it has been known for a long time that there is asymmetry between the two hemispheres of the cortex. The memory and learning deficits exhibited by a particular brain region were observed in a group of stroke patients, while the expertise of a mouse population being switched on was found in another mouse group of stroke patients,” said Siva. “What we have been able to do is to identify a new interaction where neurons that are both engaged in language processing have a shared effect.”
The sibling hemispheres of the excitatory neocortex continue to work independently from each other and social contact is essential for the fine motor skills reflected in speech and hand motions. In the new study, neurons that express only the Wellcome Spence switch, prompting movement of extremities, responded when the mice began to express the Bubble-1 gene.
“These two hemispheres share many of the same memory, access the same information, share information about other sensations. They are, therefore, very close companions,” says Nam. The work suggests that the resulting cognitive flexibility is measurably enhanced through the expression of the Wellcome Spence-switch and brings the brilliant neuroscientist renowned through the work “The neuroplasticity is not a single-thinker,” Siva concludes.