Abstract: Auditory language comprehension plays an important role in interpersonal communication in daily life, however, we still do not fully understand its underlying neural mechanisms. Electrical brain stimulation (EBS) is an experimental technique with a very long history but has only recently been widely used on human subjects. By performing electrical stimulation, analyzing the induced transient behavioral functional changes and recording the neural activity, it is possible to directly reveal the functional roles within brain regions and the effective connections between brain areas during auditory language processing. Electrical brain stimulation offers a very high spatial and temporal resolution and employs recording electrodes that can reach deep into subcortical areas. Given these unique advantages, electrical brain stimulation has received increasing research interest in recent years.
Auditory language processing is a fairly complex process and involves a wide range of brain areas. In general, the process of auditory language processing in the brain is as follows: incoming speech from the external environment enters the thalamus, which then passes to the auditory cortex (AC) for primary processing of acoustic-phonological information, followed by more advanced language processing in the temporal and frontal language areas. In addition, frontal language areas may also generate speech-related predictions that feedback to temporal language areas to facilitate auditory language processing. Electrical brain stimulation allows relatively flexible cortical or subcortical stimulation in subjects who were performing an auditory language task. By comparing the differences in task performance before and after electrical stimulation, the relationship between stimulated brain areas and cognitive function could be analyzed and thus the distribution of functionally relevant areas could be mapped. Besides, electrical brain stimulation, as a means to reflect effective connections between brain areas, can also reveal the functional connections during auditory language processing. Therefore, this paper, from the perspective of auditory language processing, is divided into three parts: thalamus and auditory cortex, auditory language processing within auditory cortex, and higher language cortex and auditory cortex. By reviewing the available studies on electrical brain stimulation during auditory language processing, the functional characteristics of the brain areas involved in auditory language processing and the information transfer mechanisms between different brain areas are summarized, providing a new perspective for further exploring the mechanisms of auditory language processing and the application of electrical brain stimulation techniques in the study of brain function. Electrical brain stimulation has broad application prospects in auditory language research, and the increased application of this technique will also bring more causal evidence on the brain function and connectivity, providing the possibility of further understanding the neural mechanisms of auditory language processing.

Key words: electrical brain stimulation, auditory language processing, effective connectivity