The Committee on Hearing Loss of Japan Audiological Society conducted a review to determine what kind of auditory tests are used to evaluate the efficacy of rehabilitation and the status of rehabilitation for hearing disorders in Japan and overseas, to grasp the current situation. The subjects were patients with cochlear implants, hearing aids, or tinnitus. We report the results herein.

　 The auditory steady-state response (ASSR) is an objective audiometric assessment tool that is widely used in clinical practice, particularly for pediatric patients with hearing loss. Unfortunately, conventional ASSRs can take up to two hours to complete due to the tininess of the responses that can be elicited by each stimulus, such as an amplitude-modulated (AM) or frequency-modulated (FM) tone. These stimuli result in sequential and time-delayed responses from the frequency areas of the cochlea, which require repeated stimulation to obtain sufficient recordings. This extended testing time poses a challenge, particularly when the patient is a neonate or young child, and this has been addressed by the development of next-generation ASSR with a new type of stimulus, a “chirp,” which elicits simultaneous responses from all frequency areas of the cochlea. This results in enhanced neural synchronicity in the cochlear nerve fibers and produces elicits auditory responses of higher amplitudes that can shorten the ASSR testing times.

　 The purpose of this review is to discuss the efficacy and remaining challenges of next-generation ASSR using chirp stimuli as compared to the conventional ASSR assessment method.

　 Hearing evaluation using auditory evoked responses can be performed in children and adults of any age. In clinical practice, the auditory steady-state response (ASSR) and auditory brainstem response (ABR) are mainly used to evaluate hearing in infants and children as well as patients with functional hearing loss, in whom psychological tests such as play audiometry and pure tone audiometry (PTA) are difficult to administer. ASSR is a highly useful test in that it can estimate the hearing ability in low and middle frequency bands such as 500 Hz and 1000 Hz, which is difficult to evaluate by click-evoked ABR. The ASSR using chirp tones, a frequency sweep tone that has recently become commercially available, is called next-generation ASSR, and a number of studies have reported its usefulness. In this paper, I will outline the techniques and tricks related to this test in actual clinical practice, such as the recording parameters, points to be considered in the testing, and method of estimation of the hearing level, from the viewpoint of a speech-language-hearing therapist who actually performs testing with experience in using the next-generation ASSR.

　 We consider that objective evaluation of auditory processing tasks and auditory processing disorder (APD) is necessary in patients who have hearing difficulties with normal hearing and word recognition score. Therefore, we developed an application that runs on an iPad. At first, we determined the average and cutoff values in 15 normal adults without any hearing problems. Then, we administered the same tasks to 5 adults (2 males, 3 females) with hearing difficulties. We can observed lower scores in the competing task, gap detection task, auditory figure & ground task, duration pattern task and pitch pattern task. Differences in task performance were found among the subjects.

　 We investigated the relationship between age-related changes in categorical perception and speech perception ability. The subjects were 18 late middle-aged or older adults (mean: 73.3 years; age range: 63-77 years) with age-appropriate hearing and 15 younger adults. The VOT discrimination task, which consists of a seven-step unvoiced phoneme /pa/ to voiced /ba/continuum, was presented to the subjects on the laptop and audiometer. The results showed that a large percentage of the late middle-aged/ older adults had difficulty categorizing the two consonants correctly as compared with the younger group. There were significant differences in the hearing levels and Reception Thresholds for Sentences (RTS) in the Hearing in noise test (HINT-J) between the subjects who could and could not categorize the consonants. There were cases among the older adults who could not categorize the consonants, even if their hearing was normal. Understanding the relationship between the categorization performance and speech perception ability could improve our understanding of age-related hearing difficulties.