Behaviour

Learning and memory, perception, attention and other psychological phenomena are principal components of how the brain processes information, and are categorised as cognitive processes. In recent years, there has been enormous interest in finding how the nerve cells and molecules of the brain participate in cognition. This interest is not only of intellectual importance but also of great medical significance, as diseases such as Alzheimer's, schizophrenia and autism are diseases of cognition.

A key discovery that lead to the G2C program was that a collection of proteins known as the NRC (NMDA Receptor Complex) or MASC (MAGUK-Associated Signalling Complex) are involved in cognition and diseases of the nervous system (Husi, Ward, Choudhary, Blackstock & Grant, 2000). These proteins, which are bound together in a multiprotein complex, process the conversion of electrical activity into biochemical activity at the synapse (the junction between nerve cells). The NRC contains 185 proteins, of which 48 have been implicated in 54 different nervous system disorders in humans (Grant et al, 2005), which although a strikingly high number is likely to grow.

In the G2C program, we have scientists with expertise in human and animal behaviour, as well as human and animal genetics. These scientists identify gene mutations in mice and humans, then test behaviour in psychological tests of cognitive function. For example, there are different forms of learning, and one form known as declarative learning involves NRC proteins. Defects in declarative learning impair the ability to learn spatial or navigational information, leaving intact procedural behaviours such as motor activities engaged with, say, learning to swing a tennis racquet.

Figure 1: A basic T-maze for testing learning in mice. A food reward is placed in one end of the 'T'. The mouse is released from the centre of the 'T' and graded on how quickly it finds the reward. This experiment is non-invasive and puts very little stress on the mouse.

Very little is known about the molecular basis of human behaviours in general and the G2C program will focus on cognitive behaviours, and aim to not only provide insights into this aspect of brain function, but also aim to test approaches that may later be applicable to a broader range of important behaviours.