Common memory retrieval network in humans and monkeys Macaque posterior parietal cortex activated during memory retrieval

Recent human imaging studies revealed the involvement of the posterior parietal cortex (PPC) in memory retrieval, in addition to the medial temporal lobe including the hippocampus. However, the PPC is evolutionarily developed in humans and its memory-related functions are less well understood. It is also unknown if these PPC roles are unique to humans using language.

Recognition memory is the ability to recognize previously encountered items. Two areas in the macaque posterior parietal cortex (intraparietal sulcus, inferior parietal lobule) were activated during correct recognition.© Kentaro Miyamoto
Professor Yasushi Miyashita, graduate student Kentaro Miyamoto and their colleagues at the Department of Physiology in the Graduate School of Medicine have conducted functional magnetic resonance imaging (fMRI) experiments using awake macaque monkeys that perform a cognitive task (serial probe recognition task) and compared the task-related activities (blood oxygenation level-dependent signals) with those of humans. They revealed for the first time that the macaque PPC is activated during successful memory retrieval as it is for humans. Furthermore, two memory retrieval-related regions identified in macaque PPC were dissociated, both functionally and anatomically. This differentiation suggested that these two PPC areas correspond to different areas in human PPC. Further examination of memory-related activities in monkey PPC in combination with electrophysiological and pharmacological methods will promote a better understanding of memory retrieval functions in the PPC. In the future, this research is expected to have clinical applications for treatment of memory disorders.
Paper
Kentaro Miyamoto, Takahiro Osada, Yusuke Adachi, Teppei Matsui, Hiroko M. Kimura, Yasushi Miyashita,
“Functional Differentiation of Memory Retrieval Network in Macaque Posterior Parietal Cortex”,
Neuron 77(4) 2013: 787-799, doi: 10.1016/j.neuron.2012.12.019.
Article link
Links
Department of Physiology Laboratory of Integrative Physiology