AIM： To determine by brain functional magnetic resonance imaging （fMRI） whether cerebral processing of non-visceral stimuli is altered in irritable bowel syndrome （IBS） patients compared with healthy subjects. To...AIM： To determine by brain functional magnetic resonance imaging （fMRI） whether cerebral processing of non-visceral stimuli is altered in irritable bowel syndrome （IBS） patients compared with healthy subjects. To circumvent spinal viscerosomatic convergence mechanisms, we used auditory stimulation, and to identify a possible influence of psychological factors the stimuli differed in their emotional quality. METHODS： In 8 IBS patients and 8 controls, fMRI measurements were performed using a block design of 4 auditory stimuli of different emotional quality （pleasant sounds of chimes, unpleasant peep （2000 Hz）, neutral words, and emotional words）. A gradient echo T2＊weighted sequence was used for the functional scans. Statistical maps were constructed using the general linear model. RESULTS： To emotional auditory stimuli, IBS patients relative to controls responded with stronger deactivations in a greater variety of emotional processing regions, while the response patterns, unlike in controls, did not differentiate between distressing or pleasant sounds. To neutral auditory stimuli, by contrast, only IBS patients responded with large significant activations. CONCLUSION： Altered cerebral response patterns to auditory stimuli in emotional stimulus-processing regions suggest that altered sensory processing in IBS may not be specific for visceral sensation, but might reflect generalized changes in emotional sensitivity and affectire reactivity, possibly associated with the psychological comorbidity often found in IBS patients.展开更多
The binaural masking level difference(BMLD)is a psychoacoustic method to determine binaural interaction and central auditory processes.The BMLD is the difference in hearing thresholds in homophasic and antiphasic cond...The binaural masking level difference(BMLD)is a psychoacoustic method to determine binaural interaction and central auditory processes.The BMLD is the difference in hearing thresholds in homophasic and antiphasic conditions.The duration,phase and frequency of the stimuli can affect the BMLD.The main aim of the study is to evaluate the BMLD for stimuli of different durations and frequencies which could also be used in future electrophysiological studies.To this end we developed a GUI to present different frequency signals of variable duration and determine the BMLD.Three different durations and five different frequencies are explored.The results of the study confirm that the hearing threshold for the antiphasic condition is lower than the hearing threshold for the homophasic condition and that differences are significant for signals of 18ms and 48ms duration.Future objective binaural processing studies will be based on 18ms and 48ms stimuli with the same frequencies as used in the current study.展开更多
文摘AIM： To determine by brain functional magnetic resonance imaging （fMRI） whether cerebral processing of non-visceral stimuli is altered in irritable bowel syndrome （IBS） patients compared with healthy subjects. To circumvent spinal viscerosomatic convergence mechanisms, we used auditory stimulation, and to identify a possible influence of psychological factors the stimuli differed in their emotional quality. METHODS： In 8 IBS patients and 8 controls, fMRI measurements were performed using a block design of 4 auditory stimuli of different emotional quality （pleasant sounds of chimes, unpleasant peep （2000 Hz）, neutral words, and emotional words）. A gradient echo T2＊weighted sequence was used for the functional scans. Statistical maps were constructed using the general linear model. RESULTS： To emotional auditory stimuli, IBS patients relative to controls responded with stronger deactivations in a greater variety of emotional processing regions, while the response patterns, unlike in controls, did not differentiate between distressing or pleasant sounds. To neutral auditory stimuli, by contrast, only IBS patients responded with large significant activations. CONCLUSION： Altered cerebral response patterns to auditory stimuli in emotional stimulus-processing regions suggest that altered sensory processing in IBS may not be specific for visceral sensation, but might reflect generalized changes in emotional sensitivity and affectire reactivity, possibly associated with the psychological comorbidity often found in IBS patients.
文摘The binaural masking level difference(BMLD)is a psychoacoustic method to determine binaural interaction and central auditory processes.The BMLD is the difference in hearing thresholds in homophasic and antiphasic conditions.The duration,phase and frequency of the stimuli can affect the BMLD.The main aim of the study is to evaluate the BMLD for stimuli of different durations and frequencies which could also be used in future electrophysiological studies.To this end we developed a GUI to present different frequency signals of variable duration and determine the BMLD.Three different durations and five different frequencies are explored.The results of the study confirm that the hearing threshold for the antiphasic condition is lower than the hearing threshold for the homophasic condition and that differences are significant for signals of 18ms and 48ms duration.Future objective binaural processing studies will be based on 18ms and 48ms stimuli with the same frequencies as used in the current study.
