Action execution and observation in macaque monkeys: Towards social systems neuroscience

Action execution and observation are fundamental aspects of primate live. Humans and monkeys perform hand actions to manipulate food or objects to achieve goals from basic survival to social communications. Successful communication and interactions with others require constant monitoring of others’ actions in order to plan and facilitate own actions. Action execution and observation are not independent processes but could be influenced by many other cognitive factors such as learning or social contexts. Neuroimaging and electrophysiology studies have identified a number of cortical regions in human and monkeys that encode action related information, including visual and motor areas as well as mirror neuron regions that contains neurons which respond both to executed and observed actions. However, it still remains unclear how action representations in primate brain modulate due to learning and social context. To date, evidence of action representations at whole brain level has been obtained mostly using non-invasive neuroimaging in humans, while the majority of neuronal evidence at single cell level comes from monkeys, yet from a limited number of regions. Therefore, non-human primate fMRI offers a valuable model and technique to bridge a link between evidence from humans with indirect measurements of brain activity based upon hemodynamics and single neuron spiking activity in monkey brain. Using fMRI technique in monkeys, we will investigate effects of cognitive factors such as categorization learning and various social contexts (alone or with presence of another conspecific) on brain representations of observed and executed actions as well as how and to what extent different brain networks engage in these cognitive processes. These experiments will shed light onto the primate brain networks involved in representing own and others` actions and will provide much needed insights into the modulatory effects of social context on social and cognitive brain networks.