Session 2 - Human memory: origins, mechanisms and meanings
The second session of the meeting entitled Human memory: origins, mechanisms and meanings is moving form the molecular basis of the storage of different forms of biological information considered in the first session, to a consideration of how what we understand as “brain memory” is generated and stored. The first speaker will address how memory has evolved, starting with a simple creature, the flatworm, that utilizes memory to recall prior experience in order to make decisions involving directional movement, for example to find food. The speaker will then consider how primate memory evolved, utilizing elements from the many diverse life forms that arose in evolution. He hypothesizes that two quantum leaps in the development of memory occurred and that ultimately the primates developed a more complex memory system from that found in other mammals, allowing vocal communication, originally advantageous in the competition for food.
The second speaker will then move directly to our species, the human, and consider how memory for so-called autobiographical events, (unique to individuals), develop during early childhood. He utilizes the monkey as a model and studies the hippocampus, an area of the brain where memory is thought to be stored. This is studied using molecular and neuroanatomical techniques such as the addition and maturation of new groups of neurons in defined hippocampal areas. He compares this to the time line of the emergence of spatial memory of allocentric space (positioning ourselves with reference to external cues) and draws a correlation between the structural and functional maturation of the brain.
The third speaker in this session will consider the enigmatic process of sleep. Although it is in the awake brain that memories are optimally encoded and retrieved, it is during sleep that memories are consolidated. The speaker will discuss the relationship between the different phases of sleep and the activation of neural circuits in both hippocampus and cortex and how these interplay with slow oscillations of the neural network during long-term memory storage.