Brain function and macromolecules. 3. Uridine incorporation into polysomes of mouse brain during short-term avoidance conditioning

Brain function and macromolecules. VI. Autoradiographic analysis of the effect of a brief training experience on the incorporation of uridine into mouse brain

In agreement with the data of Beach et al. (these Proceedings, 62, 692 (1969)) on the effects of avoidance training on protein synthesis, we report autoradiographic evidence for the increased incorporation of radioactive uridine into limbic system structures of the brains of trained mice. There is also a decreased incorporation into the outer layers of the neocortex. The observed responses in labeling are restricted to the nuclei of neurons. The significance of these changes in brain function is not known but they may be related to those processes of the memory consolidation phenomenon affected by inhibitors of protein and RNA synthesis.

The biochemical basis of long-term memory

Learning and memory are important elements of our daily lives, familiar to all through introspection. Yet the mechanisms underlying these processes are still for the most part unknown. Here are problems which combine a maximum of intrinsic and practical interest with a minimum of actual knowledge and understanding. Years of our lives are dedicated to the formation of certain long-term memories and behaviour patterns, yet we have only rudimentary notions of how such ‘schooling’ is best accomplished. There is no certainty in any aspect of the process. We are not sure whether relatively few cells or millions participate in a memory trace; whether these cells change as a whole, or whether the changes are limited to synaptic regions. In fact, we cannot be certain whether the changes are confined to the neurones or whether the glia also participate.