I've heard the term "neural slowing" used in aging literature. What exactly does this mean?
The neural slowing hypothesis proposes that age-related declines in neural processing speed may underlie a broad range of cognitive deï¬ cits in older persons. The aging neurological system does not operate as quickly and efficiently as it has in the past. When you consider the cognitive implications of aging, and how older persons perform tasks, it doesn't appear that long term memory or linguistic issues are at play but rather the ability for things to happen quickly within the nervous system seems to slow down. As you know the auditory system requires a lot of synchronized and rapid firing. Good ABR waveforms result from a lot of highly synchronized, very rapid responses of the auditory nervous system in response to acoustic stimuli. The neural slowing hypothesis explains that neural events don't happen as rapidly, hence the reason why short term memory is affected, sensorimotor reaction time slows, and why processing and decision speed are decreased as we age.
Editor's note: This Ask the Expert was taken from Dr. Schum's recorded course Providing Amplification to the Aging Auditory System, which examines aging from an audiological and cognitive perspective, and discusses the implications for clinical practice. To register to view the recorded course, please visit: www.audiologyonline.com/ceus/recordedcoursedetails.asp?class_id=17615
Don Schum currently serves as Vice President for Audiology & Professional Relations for Oticon, Inc. Previous to his position at Oticon in Somerset, Don served as the Director of Audiology for the main Oticon office in Copenhagen Denmark. In addition, he served as the Director of the Hearing Aid Lab at the University of Iowa School of Medicine (1990-1995) and as an Assistant professor at the Medical University of South Carolina (1988-1990). During his professional career, Dr. Schum has been an active researcher in the areas of Hearing Aids, Speech Understanding, and Outcome Measures. ( B.S. in Speech & Hearing Science, University of Illinois;M.A. in Audiology, University of Iowa;Ph.D. in Audiology, Louisiana State University.