Measuring Behavior 2005: Morris

Moving on from spatial learning to episodic-like and semanticlike memory

R.G.M. Morris

Division of Neuroscience, Edinburgh University, Edinburgh, United Kingdom

Spatial learning - in T-mazes, radial-mazes and the water maze - has long been a popular choice amongst behavioral neuroscientists interested in the neurobiology of learning and memory. Drawing largely on studies using the water maze, I shall describe classical findings that have emerged over the past 20 years, ranging from standardized spatial reference memory protocols through to delayed-matching-to-place and other procedures expressly designed to address specific theoretical issues relating to hippocampal function, the role of synaptic plasticity in memory, and animal models of neurodegenerative disease. A key theme is that the water maze, no less than types of apparatus, is merely an apparatus; it is important to maintain a sharp distinction between the watermaze as an apparatus and the watermaze as a set of distinct training protocols. The value and pitfalls of different procedures will be highlighted.

Increasingly, students of the neurobiology of learning and memory are interested in investigating wider issues, notably how spatial and contextual memory can provide a framework for remembering events. My research group has recently developed a new paired-associate paradigm for investigating episodic-like and semantic-like memory in animals. We call the apparatus the ‘Event Arena’ and within it, rats are trained to find a specific flavor of food in a particular location. Learning may take place over 1-trial (episodic-like), or over several trials and days (semantic-like). The characteristics of the two styles of training will be described, together with illustrations of the flexibility of this new appetitive paradigm for investigating a wider range of issues, such as the puzzle of system-level memory consolidation. Certain implications of the apparatus for the development of new automated systems for tracking animals and for automatically recognizing their behavioral actions will also be discussed.

Paper presented at Measuring Behavior 2005 , 5^th International Conference on Methods and Techniques in Behavioral Research, 30 August - 2 September 2005, Wageningen, The Netherlands.