Scientific Understanding of Consciousness
FAPs — Persistent Activity
Nature 461, 50-51 (3 September 2009)
Neuroscience: Persistent feedback
Hyojung Seo & Daeyeol Lee
Hyojung Seo and Daeyeol Lee are in the Department of Neurobiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
Persistent activity in the prefrontal cortex and basal ganglia may be crucial for learning correct actions through experience.
Neurons in the primate prefrontal cortex and basal ganglia display persistent activity that is related to the outcomes of previous actions.
The task of forming an association between a particular sensory event, a behavioural response and the outcome of this response is not trivial, as a particular outcome might be preceded by multiple sensory stimuli and responses. To discover which of these events are related, it is often necessary to experience the same sequence of sensory stimuli, actions and outcomes repeatedly. Moreover, the sensory and motor events that need to be remembered together are often transient, whereas the outcome of an action may be revealed only after a long delay. Therefore, the information about various sensory and motor events must be stored temporarily before the long-lasting memory about their relationship can be formed.
A mechanism for storing information about the relationship between multiple events might be persistent neural activity, which is sustained beyond the duration of the initiating event. Some neurons in the prefrontal cortex and basal ganglia carry information about previous actions. The prefrontal cortex and basal ganglia might be essential brain areas for storing information about action–outcome associations. Neurons in the prefrontal cortex and basal ganglia predominantly encoded the outcome of the animal's choice.