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M Velmans

Publications and source records attributed to M Velmans.

6 recordsLinked to original sources

A reflexive science of consciousness.

Classical theories of consciousness make it difficult to see how it can be a subject of scientific study. In contrast to physical events, it seems to be private, subjective and viewable only from a subject's first-person perspective. But much of psychology does investigate conscious experience, which suggests that classical theories must be wrong. An alternative, 'reflexive' model is proposed in which the external phenomenal world is viewed as part of consciousness rather than apart from it. Observed events are 'public' only in the sense of 'private experience shared'. Scientific observations are 'objective' only in the sense of 'intersubjective'. Observed phenomena are 'repeatable' only in that they are sufficiently similar to be taken for 'tokens' of the same event 'type'. This closes the gap between physical and psychological phenomena. Studies of consciousness face methodological difficulties. An experimenter E and a subject S may have 'symmetrical access' to events in the outside world in so far as they perceive those events (from a third-person perspective) using similar exteroceptive systems; but their access to the subject's body, brain and experience is 'asymmetrical' (E's third-person perspective versus S's first-person perspective). In so far as E and S each have partial access to such events, their perspectives are complementary. Systematic investigation of experience requires merely that experiences are potentially shareable, intersubjective and repeatable. In this the conditions for a science of consciousness are no different to those for a science of physics.

Animals↗

The effect of frequency transposition on the untrained auditory discrimination of congenitally deaf children.

Various frequency lowering schemes have been developed for use with deaf people who have little or no measurable hearing in the high frequencies. In general, results of studies evaluating such schemes have been discouraging, except for studies evaluating a frequency recoding device devised by Velmans (1973a). Previous evaluation studies with this device have demonstrated that FRED transposition can improve the auditory discrimination of certain subjects with sensorineural deafness after training (e.g. Velmans and Marcuson, 1980; Velmans et al., 1982; Velmans et al., 1988). Using selection criteria developed in the 1988 study, the current study evaluated the effect of FRED transposition on the untrained auditory discrimination of eight congenitally deaf students, aged between 7 years 2 months and 14 years 10 months with high frequency hearing losses. Results demonstrated that FRED transposition significantly enhanced the auditory discrimination of consonants in the high speech frequencies for the subject group. This suggests that FRED transposition may produce some benefits in everyday situations even without formal training. Evaluation tests with and without transposition, such as those used in this study, may provide one means of selecting congenitally deaf people who would be likely to benefit from using FRED aids.

Acoustic Stimulation↗

The acceptability of spectrum-preserving and spectrum-destroying transposition to severely hearing-impaired listeners.

Various devices have been constructed to lower the frequency of speech sounds to make them accessible to those with hearing in the low frequencies only. In the present experiment two such devices are compared. One device, the FRED (frequency recoding device) maps the 4-8 kHz region on to the 0-4 kHz region in a way that preserves the spectral pattern of transposed signals. The other device, the Oticon TP 72, converts signals in the 4-8 kHz region into low frequency noise (below 1.5 kHz). Both devices combine transposed information with conventionally amplified speech. It was found that untrained adults with acquired sensory-neural hearing losses opted to supplement conventional amplification with FRED transposition on 365 out of 576 occasions, to improve the clarity of speech sounds. Under the same conditions they opted to use Oticon transposition on significantly fewer (32 out of 576) occasions. Subjective preferences for FRED as opposed to Oticon transposition were also highly significant. It was concluded that for the subject group in question a transposition which preserves the relative spectrum of transposed sounds is initially more acceptable than one which uses high-frequency signals to modulate low-frequency noise.

Hearing Aids↗