Biomedical subjects

M Desgagné

Publications and source records attributed to M Desgagné.

4 recordsLinked to original sources

PubMed1992

[Multivariate study of auditory perception using multi-electrode cochlear implants].

The goal of this study was to determine the influence of auditory and cognitive factors in hearing or listening mechanisms with the Nucleus multielectrode cochlear implant. Accordingly, hearing sensitivity, psycho-acoustical masking functions and measures of temporal resolution were obtained from 14 adults with acquired deafness. In addition, six measures of open-set speech discrimination were introduced to represent a possible contribution of cognitive factors. Results indicated the contribution of both auditory and cognitive factors to speech understanding. Cognitive factors were most influential. Differences were also found in the relative importance of various cognitive factors, both before and after an intensive aural rehabilitation program. Initially, subjects relied more heavily on their ability to make efficient use of the linguistic redundancy of speech. At the end of the program, they paid more attention to speech acoustics, as a result of enhanced auditory spectral analysis and temporal resolution at about 2 kHz.

Adolescent↗

PubMed1990

Multielectrode cochlear implantation in children: the Quebec experience.

The Quebec Cochlear Implant Research Program has implanted three children since August 1987. This paper reports the results obtained with these children. All of them improved their auditory abilities with cochlear implantation and training. However, the abilities which spontaneously recovered following implantation, the speed of improvement, and the overall level of performance are different from one child to the other. Our data suggest that the age at onset of hearing loss, and possibly the number of years of deafness, may be related to the differences in performance.

Age Factors↗

PubMed1989

Cochlear implantation in Quebec city: auditory performance in a recently trained patient.

The Quebec Cochlear Implant Research Program has implanted nine patients since 1984. At the same time, we have been developing some original rehabilitative material for these French speaking patients. This paper reports the results obtained with our last adult patient. With his implant, J-P.F. has clearly improved his auditory response to sounds. After the training period, he demonstrated good abilities in detection, discrimination, identification and comprehension of sounds, phonemes, words and sentences. His lipreading has improved. The performance observed with this patient is comparable with the data reported in other studies using the same implant device.

Adult↗

PubMedDate not supplied

Temporal variations in microsomal lipid peroxidation and in glutathione concentration of rat liver.

The temporal variation in the NADPH-dependent lipid peroxidation and glutathione-S-transferase activity and in the concentration of cytosolic and microsomal proteins and in reduced glutathione of rat liver were investigated at 0100, 0500, 0900, 1300, 1700, and 2100 in male Sprague-Dawley rats synchronized to a 12-hr light-dark cycle. Highly significant time-dependent variations were obtained in the microsomal rate of lipid peroxidation, and in the concentration of reduced glutathione and cytosolic and microsomal protein. The maximal mean values for the lipid peroxidation, for the concentration of reduced glutathione, and of cytosolic and microsomal proteins were obtained at 1300, 0900, 0100 and 2100, respectively, whereas the corresponding minimal values were determined at 0100, 1700, 0900, and 1700. There was no temporal variation in the glutathione-S-transferase activity of rat liver. The temporal variation in microsomal peroxidation and in the concentration of reduced glutathione exhibited a characteristic circadian rhythm. There was no reverse relationship between the daily variation in the rate of microsomal lipid peroxidation and the hepatic concentration of reduced glutathione.

Animals↗