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Cochlear implants provide individuals who are deaf with access to speech. Although substantial advancements have been made by novel technologies, there still is high variability in language development during childhood, depending on adaptation and neural plasticity. These factors have often been investigated in the auditory domain, with the mismatch negativity as an index for sensory and phonological processing. Several studies have demonstrated that the MMN is an electrophysiological correlate for hearing improvement with cochlear implants. In this study, two groups of cochlear implant users, both with very good basic hearing abilities but with non-overlapping speech performance (very good or very poor speech performance), were matched according to device experience and age at implantation. We tested the perception of phonemes in the context of specific other phonemes from which they were very hard to discriminate (e.g., the vowels in /bu/ vs. /bo/). The most difficult pair was individually determined for each articipant. Using behavioral measures, both cochlear implants groups performed worse than matched controls, and the good performers performed better than the poor performers. Cochlear implant groups and controls did not differ during time intervals typically used for the mismatch negativity, but earlier: source analyses revealed increased activity in the region of the right supramarginal gyrus (220±260 ms) in good performers. Poor performers showed increased activity in the left occipital cortex (220±290 ms), which may be an index for cross-modal perception. The time course and the neural generators differ from data from our earlier studies, in which the same phonemes were assessed in an easy-to-discriminate context. The results demonstrate that the groups used different language processing strategies, depending on the success of language development and the particular language context. Overall, our data emphasize the role of neural plasticity and use of adaptive strategies for successful language development with cochlear implants.

The use of the effective antineoplastic agent cisplatin is limited by its serious side effects, such as oto- and nephrotoxicity. Ototoxicity is a problem of special importance in children, because deafness hampers their language and psychosocial development. Recently, organic cation transporters (OCTs) were identified in vitro as cellular uptake mechanisms for cisplatin. In the present study, we investigated in an in vivo model the role of OCTs in the development of cisplatin oto- and nephrotoxicity. The functional effects of cisplatin treatment on kidney (24 hours excretion of glucose, water, and protein) and hearing (auditory brainstem response) were studied in wild-type and OCT1/2 double-knockout (KO) mice. No sign of ototoxicity and only mild nephrotoxicity were observed after cisplatin treatment of knockout mice. Comedication of wild-type mice with cisplatin and the organic cation cimetidine protected from ototoxicity and partly from nephrotoxicity. For the first time we showed that OCT2 is expressed in hair cells of the cochlea. Furthermore, cisplatin-sensitive cell lines from pediatric tumors showed no expression of mRNA for OCTs, indicating the feasibility of therapeutic approaches aimed to reduce cisplatin toxicities by competing OCT2-mediated cisplatin uptake in renal proximal tubular and cochlear hair cells. These findings are very important to establish chemotherapeutical protocols aimed to maximize the antineoplastic effect of cisplatin while reducing the risk of toxicities.

The cortical correlates of speech and music perception are essentially overlapping, and the specific effects of different types of training on these networks remain unknown. We compared two groups of vocally trained professionals for music and speech, singers and actors, using recited and sung rhyme sequences from German art songs with semantic and/ or prosodic/melodic violations (i.e. violations of pitch) of the last word, in order to measure the evoked activation in a magnetoencephalographic (MEG) experiment. MEG data confirmed the existence of intertwined networks for the sung and spoken modality in an early time window after word violation. In essence for this early response, higher activity was measured after melodic/prosodic than semantic violations in predominantly right temporal areas. For singers as well as for actors, modality-specific effects were evident in predominantly left-temporal lateralized activity after semantic expectancy violations in the spoken modality, and right-dominant temporal activity in response to melodic violations in the sung modality. As an indication of a special group-dependent audiation process, higher neuronal activity for singers appeared in a late time window in right temporal and left parietal areas, both after the recited and the sung sequences.

Communication disorders are not taught as a self-contained topic in medical education, despite their high incidence and the similarities in the way in which they present clinically.This article describes the development of an elective subject 'Phoniatrics and Pediatric Audiology' covering five topics: hearing, language, and voice as well as psychometric tests and swallowing, with the objective of teaching a basic knowledge of the anatomy, physiology, and pathophysiology of the hearing and language system as well as symptoms, diagnostics, examination, and therapy of communication disorders. It contains theoretical background, practical exercises, and demonstrations of patient examinations.After initial modifications to the course, a statistical evaluation of the last two half-years in 2006 was performed.The majority of students believe that the subject will be useful in their subsequent studies (94.2%) and medical practice (51.9%). All students affirmed that their expectations had been met by the course and they would choose it again.Uniting several communication disorders within a self-contained topic provides the opportunity to understand pathophysiological principles, similarities, and differences between normal and impaired function of the hearing and language system and voice production. In the authors' opinion, it is a reasonable inclusion in medical training recognizing the importance of communication in today's service society.

Kinder mit auditiver Verarbeitungs- und Wahrnehmungsstörung (AVWS) mit dem Subtyp Selektionsstörung haben Schwierigkeiten, Sprache im Störschall zu erkennen. Dabei wird angenommen, dass die Funktion des medioolivocochleären Bündels (MOCS) eine wichtige Rolle spielt. Wir untersuchten 27 Kinder (9 Mädchen, 18 Jungen im Alter von 5,7 bis 13,1 Jahre) mit Verdacht auf AVWS, die in der verwendeten Testbatterie Auffälligkeiten im Bereich des Sprachverständnisses mit Hintergrundgeräuschen zeigten. Hierzu wurden ein Binaural Intelligibility Level Difference Test (B.I.L.D.-Test) und ein Test zum Sprachverständnis im Störgeräusch ausgewählt. Eine Kontrollgruppe mit unauffälligen Testergebnissen wurde nach Alter und Geschlecht eins zu eins gebildet. Die Frequenzen und Prävalenzen der spontanen otoakustischen Emissionen (SOAE) beider Gruppen wurden verglichen. Die Verteilung der Frequenzen zeigte zwischen den beiden Gruppen keine signifikanten Unterschiede. Bei den Kindern mit Selektionsstörung wurde eine signifikant höhere Prävalenz der SOAE gegenüber der Kontrollgruppe festgestellt: bei 85% der Kinder mit selektiver Hörstörung ließen sich SOAE nachweisen, bei der Kontrollgruppe waren es nur 45%. Dies könnte Ausdruck einer Enthemmung der äußeren Haarzellen bei Störung des MOCS sein. Eine erhöhte Prävalenz der SOAE könnte als Anhaltspunkt für eine AVWS, Subtyp Selektionsstörung, gewertet werden.

We designed a melody perception experiment involving eight harmonic complex tones of missing fundamental frequencies (hidden auditory object) to study the short-term neuronal plasticity of the auditory cortex. In this experiment, the fundamental frequencies of the complex tones followed the beginning of the virtual melody of the tune “Frère Jacques”. The harmonics of the complex tones were chosen so that the spectral melody had an inverse contour when compared with the virtual one. Evoked magnetic fields were recorded contralaterally to the ear of stimulation from both hemispheres. After a base line measurement, the subjects were exposed repeatedly to the experimental stimuli for 1 hour a day. All subjects reported a sudden change in the perceived melody, indicating possible reorganization of the cortical processes involved in the virtual pitch formation. After this switch in perception, a second measurement was performed. Cortical sources of the evoked gamma-band activity were significantly stronger and located more medially after a switch in perception. Independent Component Analysis revealed enhanced synchronization in the gamma-band frequency range. Comparing the gamma-band activation of both hemispheres, no laterality effects were observed. The results indicate that the primary auditory cortices are involved in the process of virtual pitch perception and that their function is modifiable by laboratory manipulation.