Auditory discrimination training for tinnitus treatment: the effect of different paradigms.

Acoustic deprivation, i.e. hearing loss, is responsible for a cascade of processes resulting in reorganisation of the cortex. Tinnitus mechanisms are explained by synchronization of the neural spontaneous activity and might be related to cortical re-mapping. Auditory discrimination training (ADT) has demonstrated in both animals and humans to induce tonotopical changes in the auditory pathways through neural plasticity. We hypothesize that ADT could have some effect on tinnitus perception. The objective of this study is to compare the effect on tinnitus following two paradigms of ADT. Only patients from 20 to 60 years of age were recruited. Inclusion criteria were pure tone tinnitus of mild or moderate handicap according to the Tinnitus Handicap Inventory score (<56). ADT patients were randomized in two groups: SAME (ADT in the same frequency of tinnitus pitch, 20 patients) and NONSAME (ADT in the frequency one-octave below tinnitus pitch, 21 patients). Groups of pair of tones (70% standard tones ST, 30% deviant tones ST + 0.1-0.5 kHz) were randomly mixed for 20 min/day during 1 month. Patient had to mark when the two sounds of the pair were similar or different. Control group included 26 patients from the waiting list (WLG). Patients were also divided according to the trained frequency and the deepest hearing-impaired frequency. Outcome parameters were set up according to the answer to the question "is your tinnitus better, same, or worse with the treatment?" (RESP), the tinnitus handicap inventory (THI) and the visual analogue scale from 1 to 10 on tinnitus intensity (VAS). Tinnitus improved in 42.2% of the patients (RESP). VAS and THI scores were reduced but only THI differences were statistically significant (P = 0.003). ADT patients improved significantly compared with WLG in RESP and THI scores (P < 0.01). Training frequencies one-octave below the tinnitus pitch (NONSAME) decreased significantly THI scores compared with patients trained frequencies similar to tinnitus pitch (SAME, P = 0.035). RESP and VAS scores decreased more in NONSAME group though differences were not significant. We did not find any differences when comparing the group training the deepest hearing-impaired frequency and the group who trained other frequencies. Auditory discrimination training significantly improved tinnitus handicap compared to a waiting list group. Those patients who trained frequencies one octave below the tinnitus pitch had better outcome than those who performed the ADT with frequencies similar to the tinnitus pitch (P = 0.035).

Cortical reorganisation and tinnitus: principles of auditory discrimination training for tinnitus management.

Scientific evidence has proved reorganisation processes in the auditory cortex after sensorineural hearing loss and overstimulation of certain tonotopic cortical areas, as we see in auditory conditioning techniques. Acoustic rehabilitation reduces the impact of these reorganisation changes. Recent theories explain tinnitus mechanisms as a negative consequence of neural plasticity in the central nervous system after a peripheral aggression. Auditory discrimination training (ADT) could partially reverse the wrong changes in tonotopic representation and improve tinnitus. We discuss different studies and their efficacy on tinnitus perception and annoyance. Indications, method, dose and sound strategy need to be implemented.

Trans-electrical nerve stimulation (TENS) for somatic tinnitus.

The somatic tinnitus syndrome includes those forms of tinnitus that are associated with a somatic disorder involving the head and upper neck. It has been suggested that physiological mechanisms where interactions occur between the somatosensory and auditory systems are the etiology for that kind of tinnitus. Trans-electrical nerve stimulation (TENS) of areas of skin close to the ear increases the activation of the dorsal cochlear nucleus through the somatosensory pathway and may augment the inhibitory role of this nucleus on the CNS and thereby ameliorate tinnitus. In a prospective descriptive study of 26 patients with the probable diagnosis of somatic tinnitus we found that TENS could improve the tinnitus in 46% of the participants (23% did not hear it anymore, and in 23% its intensity was reduced). VAS scores improved from 6.5 to 6.0 after 2 weeks of treatment (p<0.01). Patients used TENS at home for 2h, once per day during 2 weeks (alternating ramped burst, 150 pps, with pulse duration of 100 micro s, amplitude 0-60 mA; average TENS intensity was 27 mA). Intermittent "typewriter" type of tinnitus was the most responsive. Somatic tinnitus without otologic disease had better response than tinnitus associated to otological causes (p=0.047).

Auditory discrimination therapy (ADT) for tinnitus management.

Auditory discrimination training (ADT) designs a procedure to increase cortical areas responding to trained frequencies (damaged cochlear areas with cortical misrepresentation) and to shrink the neighboring over-represented ones (tinnitus pitch). In a prospective descriptive study of 27 patients with high frequency tinnitus, the severity of the tinnitus was measured using a visual analog scale (VAS) and the tinnitus handicap inventory (THI). Patients performed a 10-min auditory discrimination task twice a day during one month. Discontinuous 4 kHz pure tones were mixed randomly with short broadband noise sounds through an MP3 system. After the treatment mean VAS scores were reduced from 5.2 to 4.5 (p=0.000) and the THI decreased from 26.2% to 21.3% (p=0.000). Forty percent of the patients had improvement in tinnitus perception (RESP). Comparing the ADT group with a control group showed statistically significant improvement of their tinnitus as assessed by RESP, VAS, and THI.

Consensus for tinnitus patient assessment and treatment outcome measurement: Tinnitus Research Initiative meeting, Regensburg, July 2006.

There is widespread recognition that consistency between research centres in the ways that patients with tinnitus are assessed and outcomes following interventions are measured would facilitate more effective co-operation and more meaningful evaluations and comparisons of outcomes. At the first Tinnitus Research Initiative meeting held in Regensburg in July 2006 an attempt was made through workshops to gain a consensus both for patient assessments and for outcome measurements. It is hoped that this will contribute towards better cooperation between research centres in finding and evaluating treatments for tinnitus by allowing better comparability between studies.

[Assessment of hyperacusis: the self-rating questionnaire on hypersensitivity to sound]. / Evaluación de la hiperacusia: test de hipersensibilidad al sonido.

BACKGROUND: Hyperacusis is a decreased sound tolerance. The audiological examination includes the loudness discomfort level measurement and the handicap evaluation, so we introduce the Spanish validation of the german sound intolerance questionnaire. OBJECTIVES: To update the concept of hyperacusis and to evaluate its handicap through a Spanish validation of the Geräuschüberempfindlichkeit (GUF). PATIENTS: Forty patients referred to our Tinnitus and Hyperacusis Clinic in the University Hospital, between October 2004 and February 2005. OUTCOME MEASURES: The Spanish version of the GUF was performed after transla-tion and retro-translation. Internal consistency and reliability were established. RESULTS: Spanish adaptation of the GUF and its subscales (cognitive, somatic behaviour and emotional reaction) showed a high reliability and internal consistency (Cronbach's alfa: 0.9007). Higher GUF scores were statistically demonstrated in hyperacusis patients with hearing loss (p < 0.05) or tinnitus (p < 0.05). CONCLUSIONS: Spanish adaptation of the GUF is valid, reliable and can be used in a clinical setting to quantify the impact of hyperacusis on patient's quality of life.

Auditory discrimination therapy (ADT) for tinnitus managment: preliminary results.

CONCLUSION: This clinical assay has demonstrated the efficacy of auditory discrimination therapy (ADT) in tinnitus management compared with a waiting-list group. In all, 43% of the ADT patients improved their tinnitus, and its intensity together with its handicap were statistically decreased (EMB rating: B-2). OBJECTIVE: To describe the effect of sound discrimination training on tinnitus. ADT designs a procedure to increase the cortical representation of trained frequencies (damaged cochlear areas with a secondary reduction of cortical stimulation) and to shrink the neighbouring over-represented ones (corresponding to tinnitus pitch). STUDY DESIGN: This prospective descriptive study included 14 patients with high frequency matched tinnitus. Tinnitus severity was measured according to a visual analogue scale (VAS) and the Tinnitus Handicap Inventory (THI). Patients performed a 10-min auditory discrimination task twice a day for 1 month. Discontinuous 8 kHz pure tones were randomly mixed with 500 ms 'white noise' sounds through a MP3 system. ADT group results were compared with a waiting-list group (n=21). RESULTS: In all, 43% of our patients had improvement in their tinnitus. A significant improvement in VAS (p=0.004) and THI mean scores was achieved (p=0.038). Statistical differences between ADT and the waiting-list group have been proved, considering patients' self-evaluations (p=0.043) and VAS scores (p=0.004). A non-significant reduction of THI was achieved (p=0.113).