Neural Correlates Of Auditory And Visual Working Memory In Temporal Association Cortex

Working memory(WM)is the term commonly used for the ability to maintain information in memory over a time span of a few seconds and constitutes a core component of higher cognitive functions including language,problem solving,and reasoning.The study of the neural mechanisms of working memory is an important issue in the field of neuroscience.Temporal association cortex(TeA)participates in the perception of auditory and visual stimulation,and also take part in the coding of memory.But the neural mechanisms involved in working memory in TeA of rodents have remained unclear.In our study,we trained mice to perform auditory working memory task and visual working memory task respectively.The neuronal activity of TeA recorded simultaneously during mice performed the working memory tasks.It was found that in the auditory working memory task,more than half of the task-involved neurons not only showed high discharge to the sound stimulation,but also sustained the activity for about 1000 ms during the delay period;At the same time,the firing rates of these neurons also exhibited significant differences for different frequency auditory stimulation during the cue period and delay period of the task.The sustained high discharge of neurons is the representation of the animal's short-term storage of stimulus information;The selectivity for auditory information reflected the coding of sensory stimuli by neurons,and also maintains higher stimuli selectivity during the delay period.These results suggest that the temporal association cortex plays a crucial role in memory retention during the auditory working memory task.What kind of neural mechanism does the temporal association cortex participate in visual working memory,and does the neurons' activities show similarities to auditory working memory? Then we trained the mice that completed the auditory working memory task to perform a visual working memory task,while recording the electrical activity of the neuron during the task.It was found that more than half of the task-involved neurons showed sustained high discharge during the delay period.These delayed high-discharge neurons exhibited strong selectivity for spatial information.These results provide that the temporal association cortex neurons have a higher delay-period discharge in the auditory and visual working memory tasks,and there is similar neural mechanisms for temporal association cortex participating in the auditory and visual working memory tasks.Our findings provide a basis for the studies of neural circuits in working memory.