Although there are several drugs and experimental conditions that can block cognitive function and impair learning and memory, researchers have recently shown that some drugs can actually improve cognitive function.

The new multi-national study, published in the 21 February issue of the open-access journal PLoS Biology, reveals that these findings may implicate scientists’ understanding of cognitive disorders like Alzheimer’s disease.

There are trillions of neuronal connections, called synapses in the human brain that are dynamic and constantly change in strength and property. This pattern of activity, known as synaptic plasticity, controls people’s cognitive functions, and scientists hypothesize this to be the cellular basis for learning and memory. They also believe that changes in synaptic plasticity mechanisms are responsible for various cognitive deficits, including autism, Alzheimer’s disease and several forms of mental conditions and disorders.

Research leaders, Dr. Jose A. Esteban, Dr. Shira Knafo and Dr. Cesar Venero collaborated with researchers from The Centro de Biología Molecular Severo Ochoa and UNED in Spain, the Brain Mind Institute EPFL in Switzerland and the Department of Neuroscience and Pharmacology at the Faculty of Health Sciences in Denmark, to provide new information on the molecular mechanisms of synaptic plasticity as well as how this process may be manipulated to improve cognitive performance.

Their findings reveal that by using a small protein fragment or peptide, called FGL, derived from a neuronal protein involved in cell-to-cell communication, synapses can be made more plastic. FGL initiates multiple events inside the neuron, which leads to the synapses becoming plastic.

The researchers found that FGL in particular triggers the insertion of new neurotransmitter receptors into synapses in the brain’s hippocampus, which is known to play a role in various forms of learning and memory. Significantly, when FGL was administered to rats, the animals experienced an enhanced ability to learn and retain spatial information.

Dr. Esteban states:

“We have known for three decades that synaptic connections are not fixed from birth, but they respond to neuronal activity modifying their strength. Thus, outside stimuli will lead to the potentiation of some synapses and the weakening of others. It is precisely this code of ups and downs what allows the brain to store information and form memories during learning”.

The new findings reveal that within this framework, synaptic plasticity mechanisms can be pharmacologically manipulated in adult animals, with the goal of improving cognitive ability. Dr. Knafo concludes:

“These are basic studies on the molecular and cellular processes that control our cognitive function. Nevertheless, they shed light into potential therapeutic avenues for mental disorders where these mechanisms go awry”.

Written by Petra Rattue