The Role Of Pyramidal Neurons And Different Types Of Interneurons In Mouse Prefrontal Cortex In Auditory Working Memory

Auditory working memory refers to the short-term storage and processing of auditory information to guide the next action when individuals perform cognitive tasks.It is the basis of language cognition,reading thinking,and social communication.Half a century ago,studies found that during the delay phase of working memory tasks,there is persistently high firing of neurons in the prefrontal cortex,which is believed to be the neural basis of working memory.However,little is known about the roles of different types of cells in the prefrontal cortex and their microcircuits in working memory.In this paper,PV-Cre and Som-Cre transgenic mice were used as models,combined with auditory working memory behavior,optogenetics and behavioral optical labeling electrophysiological recording technology,to study the function of different types of interneurons and pyramidal neurons in the prefrontal cortex.Function in auditory working memory behavior in mice.Our study first found that about 30% of the neurons in the mouse prefrontal cortex had high firing during the delay period after the end of the sound stimulus,pyramidal neurons,PV interneurons and SST interneurons when completing the auditory working memory task,a considerable proportion of neurons in the cells had high firing responses during the delay period of the auditory working memory task,encoding auditory working memory.Through experiments combining auditory working memory behavior and optogenetics,we found that when the PV interneurons in the prefrontal cortex were activated during the auditory working memory delay period,the behavioral accuracy of animals decreased;when PV interneurons were inactivated,the behavioral accuracy of animals increased.When the Som interneurons were inactivated,the animals’ behavioral accuracy was not affected.In order to study the neural mechanism of behavioral changes,we further carried out research by combining behavioral and optically labeled electrode recordings,and found that when the PV interneurons in the prefrontal cortex were activated during the delay phase of the auditory working memory task,the firing responses of pyramidal neurons were inhibited,encoding the ability of working memory decreased;when PV interneurons were inactivated,the firing response of pyramidal neurons was enhanced,and the ability to encode auditory working memory was enhanced.When Som interneurons were inactivated,although the overall firing response of pyramidal neurons was enhanced,the ability to encode auditory working memory was not improved.Therefore,the results of the electrophysiological recordings explain the reasons for the above-mentioned behavioral changes.The results of this paper suggest that we may indirectly activate pyramidal neurons by inactivating PV interneurons in the prefrontal cortex during the delayed phase of working memory tasks,resulting in an increase in the firing response of pyramidal neurons in the delayed phase and an enhanced ability to encode working memory,so as to achieve the purpose of improving auditory working memory behavior.