PubMed Health⌕ Search

Biomedical subjects

D Fucci

Publications and source records attributed to D Fucci.

At least 73 records · Page 4Linked to original sources

Effect of contactor area on tactile resolution of the tongue.

Temporal resolution values for the lingual tactile sensory system were obtained from 20 normal adult subjects. Contactor areas of .128 cm2, .32 cm2, and 1.3 cm2 were used to obtain fusion thresholds for all 20 subjects. An analysis of variance indicated no significant differences among fusion thresholds for any of the contactor sizes employed. Results are discussed in comparison to other research concerned with contactor area and in terms of the nature of lingual tactile mechanoreception.

Adolescent↗

Threshold and suprathreshold correlations for the oral tactile sensory mechanism.

The possible relationship between threshold and suprathreshold responses for the lingual tactile system was investigated. Lingual vibrotactile thresholds and suprathreshold magnitude function exponents were correlated for 26 adult subjects. A statistical analysis of the correlations indicated that there was no significant relationship between thresholds and exponents. Vibrotactile threshold and suprathreshold information may be useful in increasing understanding of the complexities of oral somesthesis.

Adolescent↗

A magnitude-estimation response pool for production of lingual vibrotactile magnitudes.

The present pilot study was designed to obtain samples of numerical vibrotactile magnitude estimations from two groups of 37 randomly selected subjects (Mage = 22.04 yr.) and to determine if these numbers were statistically equivalent. Analysis showed the numerical responses of the two groups of subjects were statistically equivalent. It was suggested that they might be viewed as a representative sample of magnitude-estimation numbers that could be employed in experimentation on lingual vibrotactile magnitude production.

Adolescent↗

Stability of magnitude production scales for oral and nonoral vibrotactile mechanoreceptive systems.

The stability of oral and nonoral vibrotactile magnitude scales produced by the method of magnitude production was investigated for 11 adult subjects. Each subject was tested over four sessions separated by 1-wk. intervals. Data analyses included correlations across trials of power function slopes as well as individual adjustments of intensity. Analysis showed a lack of stability over time for the slope functions obtained on the thenar eminence but moderate stability for the functions obtained on the tongue. Individual adjustments on intensity showed consistently high correlations across trials and structures. It was concluded that the subjects' responses were guided by the imposed experimental variables and that each individual's scaling was not necessarily reflected by the correlations based on power function slopes established over the four trials.

Adolescent↗

Cutaneous temporal resolution values for "sophisticated" and "naive" subjects.

Temporal resolution values for the tactile sensory modality were obtained for two loci, the tongue and the thenar eminence of the right hand, using a two-pulse mechanical stimulus. Two groups of 11 females each, participated in this study. One group was "sophisticated" in terms of educational background and training in experimental procedure. The other group was "naive" in terms of educational background and training in experimental procedure. Analysis showed that both the tongue and hand responded similarly to the fusion task but that there was a significant difference in fusion thresholds for both structures between the sophisticated and the naive groups. The sophisticated subjects showed more acute fusion thresholds for both the tongue and thenar eminence.

Adult↗

Sensation magnitude scales for vibrotactile stimulation of the tongue and thenar eminence.

This study represents the first attempt to generate magnitude-estimation and magnitude-balance functions for the human tongue. Vibrotactile magnitude scales for the tongue and thenar eminence of the hand were investigated for nine adult subjects. The methods of magnitude estimation and magnitude production were used to obtain magnitude-balance functions for both structures. The magnitude-estimation task resulted in magnitude functions for the tongue which were similar in slope value to those found for the thenar eminence. The magnitude-production task also gave magnitude functions which were similar in slope value for the two structures.

Adolescent↗

Geographic tongue. Report of a case showing significant reduction in lingual tactile sensitivity.

A case of a 25-year-old white adult female with geographic tongue is reported. A decrease in lingual tactile sensitivity was indicated to exist as measured through mechanical vibration. This decreased lingual sensitivity remained constant over a 10-week interval, even though the patient developed an overall healthier general outlook during this period. The overt symptoms accompanying this condition also changed from day to day, but appeared to have little or no effect on the overall decreased lingual tactile sensitivity.

Adult↗

Effects of practice and instructional set on the measurement of lingual vibrotactile thresholds.

The effects on lingual vibrotactile thresholds of three different instructional sets and three different practice conditions were determined for 30 normal adult subjects. Results showed no measurable differences between thresholds obtained with the use of the three different instructional sets, but a high false alarm rate occurred for all conditions. When a subject was given practice at obtaining thresholds with a particular instructional set as a prerequisite to threshold data collection, false alarm responses disappeared. Lower (more sensitive) thresholds also were achieved when the practice condition used required the subject to provide three thresholds within 1 mu of each other before commencing with actual testing.

Adolescent↗

Lingual vibrotactile sensation magnitudes: comparison of suprathreshold responses for the tongue and hand.

The psychophysical method of magnitude production was used to obtain suprathreshold vibratory sensation magnitude functions from a group of ten young adult subjects. The test frequency was 250 Hz, and the body sites tested were the anterior midline section of the dorsum of the tongue, the thenar eminence of the right hand, and the distal pad of the middle finger of the right hand. Results showed that the mechanoreceptive mechanisms located within these three body locations can produce suprathreshold magnitude functions that are compatible with each other as well as with those described in the literature.

Adolescent↗

Lingual vibrotactile sensation magnitudes: comparison of suprathreshold responses for three different age ranges.

Vibrotactile magnitude scaling was performed on three different age groups of six normal subjects each. The psychophysical method of magnitude production was used for the scaling of vibratory stimuli applied to the anterior dorsal surface of the tongue. The older subjects produced shallower upper-slope functions than the younger subjects and also showed greater response variability. Behavioral, anatomical, and physiological factors are discussed.

Adolescent↗

Effect of lingual vibrotactile stimulation on the averaged cortical evoked response.

This study was designed to determine the feasibility of using lingual vibrotactile stimulation to elicit an averaged evoked response and to investigate the effects of two supra-threshold intensity levels of lingual vibrotactile stimulation on the electro-cortical activity of the brain. The evoked responses were analyzed according to the amplitude of N1-P2 (in microvolts). Analysis indicates that the tongue can successfully be used as a stimulus site in the elicitation of an evoked response. The amplitudes of the evoked response elicited by 2 micrometers sensation level and 5 micrometers sensation level on the tongue are essentially the same. The relative difference between these levels is not sufficient to produce significant differences in the amplitudes of their respective evoked responses.

Adult↗

Stability of magnitude-production scales for lingual vibrotactile sensation.

The stability of lingual vibrotactile magnitude scales produced by the method of magnitude production was investigated for 10 adult subjects. These subjects produced highly stable magnitude scales across two test sessions separated by 1 wk. The subjects appeared to use absolute rather than ratio scales in the magnitude-production task. A discussion of the stability of the scales is conducted with reference to the likelihood of an internal, absolute mechanism for magnitude scaling.

Adult↗

Influence of scaling range on vibrotactile power function exponents for the tongue and hand.

Intramodal range has been studied by R. Teghtsoonian (1973), who found that for magnitude-estimation procedures an increase in the scaling range will cause a decrease in the exponent of the power function. For magnitude production procedures, an increase in the scaling range will decrease the magnitude of the exponent of the power function (Teghtsoonian, 1973). The purpose of this pilot study was to investigate the influence of scaling range on the psychophysical functions obtained by the method of magnitude production for vibrotaction. Twenty subjects were randomly selected and divided into two groups of 10 subjects each. Subjects' ages ranged from 17 to 23 yr. A detailed description of the vibrotactile equipment can be found elsewhere (1). The psychophysical method of magnitude production was used to establish suprathreshold magnitude functions from the anterior midline section of the tongue dorsum and the thenar eminence of the right hand. Each subject in Group 1 received a random order of six numbers (5, 10, 15, 20, 25, 30) and was asked to adjust the magnitude of the stimulus that he was feeling to the number being presented. Each subject in Group 2 received the same random series of six numbers as Group 1, but other numbers were also randomly interspersed above, between, or below the series of six to present an expanded range of numbers for scaling. For both groups the randomized series of numbers was presented three times at each test site.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗