Auditory hallucinations are important symptoms when making a diagnosis of schizophrenia. Since normal people may also experience auditory hallucinations, there may be a spectrum of auditory hallucinations ranging from those experienced in schizophrenia to those experienced by normal people. To assess the propensity to auditory hallucinations in a non-clinical population, we selected forty items from the questionnaire in Tanno, Ishigaki, & Morimoto (1998) and developed the Auditory Hallucination-like Experience Scale (AHES). Test-retest reliability showed that the AHES was internally consistent. There were high correlations between the AHES and the STA subscale and the overall O-LIFE (especially ‘unusual experiences’), both of which are thought to be strongly related to schizophrenia. Furthermore, the rate of false positives was higher in people more prone to auditory hallucinations than in the group less prone to auditory hallucinations. Factor analysis revealed that the AHES consists of four factors. The results suggest that the AHES has high reliability and validity as a measure of susceptibility to hallucinations.

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Marasmin [S-(methylthiomethyl)-L-cysteine-4-oxide] is a pharmaceutically valuable sulfur-containing compound produced by the traditional medicinal plant, Tulbaghia violacea. Here, we report the identification of an S-oxygenase, TvMAS1, that produces marasmin from its corresponding sulfide, S-(methylthiomethyl)-L-cysteine. The amino acid sequence of TvMAS1 showed high sequence similarity to known flavin-containing S-oxygenating monooxygenases in plants. Recombinant TvMAS1 catalyzed regiospecific S-oxygenation at S4 of S-(methylthiomethyl)-L-cysteine to yield marasmin, with an apparent K_m value of 0.55 mM. TvMAS1 mRNA accumulated with S-(methylthiomethyl)-L-cysteine and marasmin in various organs of T. violacea. Our findings suggest that TvMAS1 catalyzes the S-oxygenation reaction during the last step of marasmin biosynthesis in T. violacea.

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The researches of masking made it clear that there is a bandpass like a filter in the auditory system. This is called the auditory filter and its central frequency is thought to be the frequency of an acoustic signal. If there exist this kind of filter, the authors expected that the noise image which is perceived when pure tone and noise simultaneously presented is different from the one which is perceived when noise is presented independently. The authors chose an interrupted pure tone as an acoustic signal and continuous white noise as noise, and experimented to investigate the pure tone effect on perception of white noise. As a result, two stimulus tones induced three sound images, which are sound images of continuous noise, a pure tone and pulsed noise. The sound image which listeners did not expect to hear was the pulsed noise image. This phenomenon was thought to be an auditory induction; the inducer is the sound image of the white noise presented with the silent part of pure tone of interrupted pure tone and the inducee is that of the white noise presented with pure tone part of interrupted pure tone. This pulse phenomenon suggests that pure tone change the loudness of white noise. This finding is interesting for researches of auditory mechanism and for the field of hygienics with protecting the auditory system and improving hearing under the noisy environment.

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