The importance of context in behaviour
Understanding how cognitive functions like memory and decision making are implemented by the biophysical processes in the brain is a very challenging area of neuroscience. Models have been developed recently from experimental evidence that reflect neural processes that result in decision making, memory and attention, for example. Many of these cognitive tasks can be described as context-dependent; that is, the response to the stimulus depends on factors like the goal, experience and motivation. The 'Learning context dependent behavior: neural and synaptic mechanisms' (C - Learning) project has just completed an investigation to develop a biologically realistic theoretical framework for context-dependent behaviour. C - Learning tested the model using experiments employing electrophysiology and a context-dependent trace-conditioning task with monkeys. Trace conditioning involves presentation of a conditioned (learned) stimulus and an unconditioned stimulus separated by a period of time. Project scientists developed a model based on the ability of populations of nerve synapses being able to encode the time interval between successive events. This is due to the fact that junctions between neurons possess a finite number of states. Furthermore, C - Learning showed that the monkeys behaved in a context-dependent way and identified the specific neural substrates for that behaviour. Extension of the research is expected to show that the neural biophysics behind context-dependent behaviour is a function of the general plasticity of synapses. Project scientists also aim to identify regions in the cortex responsible for context-dependent behaviour which could shed light on related pathologies as well as understanding of mental states such as intention and motivation.