Subacute Combined Degeneration of the Spinal Cord Caused by Autoimmune Gastritis.

A 68-year-old woman presented with a 2-year history of worsening unsteady gait. Her neurological examination revealed peripheral neuropathy with lower limb sensory dominance. T2-weighted imaging revealed a disorder of the posterior cervical cord. Blood test findings revealed vitamin B12 deficiency, and gastroscopy revealed typical findings of autoimmune gastritis. She received vitamin B12 supplementation, but some peripheral neuropathy symptoms persisted due to longstanding vitamin B12 deficiency. Asymptomatic patients should undergo gastroscopy to detect autoimmune gastritis, as chronic vitamin B12 deficiency causes irreversible peripheral neuropathy.

Co-Administration of Saireito Enabled the Withdrawal of Corticosteroids in an Elderly Woman with Autoimmune Hepatitis.

An 82-year-old woman with autoimmune hepatitis had been treated with 5 mg prednisolone (PSL) orally to maintain normal transaminase levels. The subsequent transaminase levels were elevated and remained unchanged despite increasing the dose of PSL to 20 mg and introducing ursodeoxycholic acid (UDCA) at a dose of 900 mg. This combined treatment with UDCA was, however, ineffective. Treatment with Saireito at a dose of 9.0 g in conjunction with PSL was then initiated, which led to the subsequent normalization of her transaminase levels. Oral administration of PSL was discontinued eight weeks after the co-administration of Saireito. The patient had a significant response to this treatment.

Audio-tactile superiority over visuo-tactile and audio-visual combinations in the temporal resolution of synchrony perception.

To see whether there is a difference in temporal resolution of synchrony perception between audio-visual (AV), visuo-tactile (VT), and audio-tactile (AT) combinations, we compared synchrony-asynchrony discrimination thresholds of human participants. Visual and auditory stimuli were, respectively, a luminance-modulated Gaussian blob and an amplitude-modulated white noise. Tactile stimuli were mechanical vibrations presented to the index finger. All the stimuli were temporally modulated by either single pulses or repetitive-pulse trains. The results show that the temporal resolution of synchrony perception was similar for AV and VT (e.g., approximately 4 Hz for repetitive-pulse stimuli), but significantly higher for AT approximately 10 Hz). Apart from having a higher temporal resolution, however, AT synchrony perception was similar to AV synchrony perception in that participants could select matching features through attention, and a change in the matching-feature attribute had little effect on temporal resolution. The AT superiority in temporal resolution was indicated not only by synchrony-asynchrony discrimination but also by simultaneity judgments. Temporal order judgments were less affected by modality combination than the other two tasks.

The sliding window of audio-visual simultaneity.

Humans exist in an environment wherein many unrelated events occur in close spatial and temporal proximity. Audio-visual timing experiments, however, have often examined only isolated pairs of sensory events. We therefore decided to assess how audio-visual timing perception would be shaped by the presence of an additional audio or visual event. We found that the point of subjective synchrony for a sensory event can be shifted away from the presence of other temporally proximate events. These interactions made audio-visual pairs seem unrelated, or asynchronous, at timings at which they had seemed synchronous when presented in isolation. This shows that the interval across which humans are insensitive to audio-visual asynchrony is not fixed, but dynamic, shaped by interactions between multiple sensory events. Importantly, we establish that these interactions can enhance the sensitivity of timing judgments. These interactions could therefore help to segregate unrelated sensory events across time. Such effects are likely to be common in the cluttered environments in which humans exist.

Feature-based processing of audio-visual synchrony perception revealed by random pulse trains.

Computationally, audio-visual temporal synchrony detection is analogous to visual motion detection in the sense that both solve the correspondence problem. We examined whether audio-visual synchrony detection is mediated by a mechanism similar to low-level motion sensors, by one similar to a higher-level feature matching process, or by both types of mechanisms as in the case of visual motion detection. We found that audio-visual synchrony-asynchrony discrimination for temporally dense random pulse trains was difficult, whereas motion detection is known to be easy for spatially dense random dot patterns (random dot kinematograms) due to the operation of low-level motion sensors. Subsequent experiments further indicated that the temporal limiting factor of audio-visual synchrony discrimination is the temporal density of salient features not the temporal frequency of the stimulus, nor the physical density of the stimulus. These results suggest that audio-visual synchrony perception is based solely on a salient feature matching mechanism similar to that proposed for high-level visual motion detection.

Temporal frequency characteristics of synchrony-asynchrony discrimination of audio-visual signals.

Temporal synchrony is a critical condition for integrating information presented in different sensory modalities. To gain insight into the mechanism underlying synchrony perception of audio-visual signals we examined temporal limits for human participants to detect synchronous audio-visual stimuli. Specifically, we measured the percentage correctness of synchrony-asynchrony discrimination as a function of audio-visual lag while changing the temporal frequency and/or modulation waveforms. Audio-visual stimuli were a luminance-modulated Gaussian blob and amplitude-modulated white noise. The results indicated that synchrony-asynchrony discrimination became nearly impossible for periodic pulse trains at temporal frequencies higher than 4 Hz, even when the lag was large enough for discrimination with single pulses (Experiment 1). This temporal limitation cannot be ascribed to peripheral low-pass filters in either vision or audition (Experiment 2), which suggests that the temporal limit reflects a property of a more central mechanism located at or before cross-modal signal comparison. We also found that the functional behaviour of this central mechanism could not be approximated by a linear low-pass filter (Experiment 3). These results are consistent with a hypothesis that the perception of audio-visual synchrony is based on comparison of salient temporal features individuated from within-modal signal streams.