Tongue Contact Research Articles

Seasonal changes in Flehmen to constant urine stimuli

Male black-tailed deer were exposed to conspecific urine samples monthly for one year. The urine samples tested were from adult male, nonestrous female, estrous female, male fawn, and female fawn. The urine was offered with and without a wire screen cover; Flehmen occurred only when direct mouth and/or tongue contact with the urine was possible. The frequency of Flehmen varied seasonally, and urine from adults released more Flehmen than urine from fawns. But there was no difference in Flehmen frequency in response to urine from adult males or estrous or nonestrous females, when presented out of context, although in a natural situation males respond more to urinating females than males.

A simple method of monitoring licking responses that is compatible with electrophysiological recording

A simple technique is described for the monitoring of drinking behavior that is compatible with concurrent recording of electrophysiological events. The technique involves transduction of the movement of a water spout induced by tongue contact during licking, to an electrical signal via a coil and magnet. An example of this technique is provided with simultaneous recording of hippocampal EEG in a rat. The advantages of this technique include simplicity of construction, low cost, and insensitivity to most extraneous factors in addition to its compatibility with electrophysiological recording.

Tongue contact duration for /t/ and /d/

Tongue contact durations for /t/ and /d/ were investigated in word‐initial position. Meaningful sentences containing the relevant phonetic contexts were spoken by four native speakers of American English. Tongue contact durations were measured by means of electropalatography. The microphone signal was also recorded. The signals were displayed together on two trace oscillograms run off at a paper speed such that each millisecond was represented by at least 1 mm of paper. Thus temporal measurements were highly accurate. Results indicated marked intersubject variability. For some subjects there was a strong relationship between consonant type and tongue contact duration, but the voiceless cognate was not always the longer. In other subjects the relationship was influenced by the following vowel. For one subject no significant difference was found between tongue contact duration for the two consonants regardless of the following vowel. A measurement of the period of voicelessness for /t/, from the cessation o...

Tongue activity in compensatory speech: The use of articulatory models to interpret acoustical data

The question addressed was whether, in compensatory speech, the vowel following a consonant articulated with an advanced or retracted tongue placement, would also show evidence of an advanced or retracted tongue posture. Palotographic data were used to determine tongue contact region for consonants. An articulatory model of tongue configuration [Harshman, Ladefoged, and Goldstein, J. Acoust. Soc. Am. 62, 693 (1977)] was used to interpret vowel formant frequency data for vowels. Additionally, vowel formant frequencies were adjusted to account for the effects of known compensatory jaw position. With jaw position corrections included the results were that vowels following a retracted or advanced articulation of sibilant and alveolar stop consonants, showed a similar retracted or advanced set of the tongue. This was not the case for vowels following /l/. Without adjustments for jaw positon the model predictions did not indicate a similarity in tongue set for vowels and consonants for any of the CV syllable types. [Work supported by NIH Grant DE‐03631.]

Physiological control of sibilant duration: Insights afforded by speech compensation to dental prostheses

Temporal relationships among tongue contact, phonation, and presence of frication were examined for /s/ and /z/. In cases where /s/ and /z/ were produced with a supraglottal articulation of the same duration, the duration of the resulting frication was 17 ms longer for /s/. The difference can be attributed to glottal activity. The presence of a unfamiliar dental prosthesis in the mouth caused the tongue to contact the alveolar ridge sooner and release later. This physiological effect was reflected in lengthening of frication for sibilants, but the acoustical consequences were greater and more reliable for /z/ than for /s/. Reasons for this difference were sought in adaptation of timing of tongue contact, and in aerodynamic conditions expected for voiced versus voiceless sibilants. A rapid adaptation of tongue contact timing was found, with the adaptation being greater for /s/. Timing of vocal fold adduction at the end of unvoiced sibilants, and its aerodynamic consequences, are suggested to consequences, are suggested to contribute to the relative stability of /s/ acoustical durations.

Effectiveness of linguapalatal place cues for a deaf speaker

The effectiveness of linguapalatal contact place cues were examined in a study of a profoundly deaf adult speaker. A 96-electrode pseudopalate was used to sense linguapalatal contact during utterance of isolated sounds, words, and short sentences. Contact was displayed by an LED array bounded by the maxillary teeth. Initial shaping procedures were directed toward establishing the/t, s, ∫/ sounds. The repertoire was then expanded to include contrating posterior plosives and the afficate /t∫/. Some attention was given to establishing high front vowels. Tongue contact patterns attained on the goal sounds from 20 treatment sessions approximated those of “normal” speakers. Pre- and postintervention intelligibility tests on nontreatment words indicated correct placement of the consonant sounds in over 80% of their occurrances. Physiological and perceptual characteristics of the changes will be discussed. [Supported by NIH Grant NS-11852-02 and HEW Grant RSA 16-P5680 7/4-11.]

Physiological control of sibilant durations

In an earlier paper [S. Hamlet and M. Stone, J. Acoust. Soc. Am. 61, S7 (A) (1977)] tongue overshoot was reported to occur on /s/ and /z/, when subjects first attempted to speak with a dental prosthesis with 4 mm of alveolar thickness. The duration of frication for /s/ under that condition was no longer than for /s/ spoken when wearing a thin prosthesis, or when speaking without a prosthesis. Duration of /z/ was greater than in natural speech. Multiple explanations exist: (1) Timing of tongue contact for /s/ may have been altered as a compensatory attempt. (2) Duration of /s/ frication may be governed more closely by laryngeal adjustments than by tongue gestures. Special modifications of a palatography system were made so that measurements of duration of tongue contact could be made with an accuracy of 1 or 2 msec. Measurements of cessation and onset of voicing were made from pretracheal accelerometer signals. Preliminary results are discussed, based on a small number of subjects. [Work supported by NIH.]

Tongue function in the salamander Bolitoglossa occidentalis

Many plethodontid salamanders feed by means of tongue projection. Aspects of this mechanism were studied in the species Bolitoglossa occidentalis under laboratory conditions. Drosophila were presented at varying controlled distances from the animal. The force and duration of tongue contact with the prey, plus the EMG activity in the tongue protractor and tongue retractor muscles, were recorded. Both force and duration of contact decreased with increasing distance of tongue projection. Various measures of protractor muscle EMG activity were independent of projection distance. Protractor and retractor muscle activities were synchronous and continued throughout the projection-retraction cycle. The latency of a ‘tongue pad to retractor muscle’ reflex was greater than the shortest durations of tongue contact. Furthermore, the longest durations of contact were always associated with the greatest forces exerted by the tongue. In the light of these findings, a model is proposed in which projection-retraction is co-ordinated by properties of the peripheral structures rather than by those of the central nervous system.

Persistence of learned motor patterns in speech

It has been noted that “spontaneous” compensations are made during speech for articulatory constraints such as clenching of the jaw. On the other hand, at least several days are required for speech adaptation to a dental prosthesis. A recording of speech and physiological data on jaw activity and tongue contacts was made at the time of initial insertion of an experimental dental prosthesis. Subjects wore the prothesis for two weeks of adaptation, after which a second recording was made, and then waited at least 1 month without experience in speaking with it. A follow‐up recording was then made with the same protocol as when the prosthesis was first inserted. Speech sounded much less disturbed by the insertion of the prothesis after a lapse of a month than it had at initial insertion—knowledge of the compensatory adjustments required had evidently been retained over that period of time. Palatographic data showed a rapid progression toward the compensatory pattern within a few repetitions of the speech sample. [Work supported by NIH.]

AN ANALYSIS OF RATS' DRINKING‐TUBE CONTACTS UNDER TANDEM AND FIXED‐INTERVAL SCHEDULES OF FOOD PRESENTATION1

Rats' lever presses and drinking-tube contacts were studied under fixed-interval schedules of food presentation and under a tandem schedule composed of three fixed intervals. One group of rats was exposed first to the tandem schedule, next to fixed-interval schedules of comparable interpellet intervals, and once again to the tandem schedule; a second group of rats was exposed first to a fixed-interval and then to the tandem schedule. Under the tandem schedule, lever presses occurred at a higher rate and were more uniformly distributed in time than under the fixed-interval schedule. Tube contacts emitted by rats exposed first to a fixed-interval schedule consisted mostly of tongue contacts, which occurred at a high rate shortly after food; tube contacts emitted by rats exposed first to the tandem schedule consisted mostly of paw contacts, which occurred at a lower rate at times other than shortly after food. Changing the schedule from fixed interval to tandem decreased the frequency of tongue contacts for all rats. Under schedules of food presentation with comparable interpellet intervals, the schedule of food presentation, rather than the rate of food delivery per se, determined the topography and temporal locus of drinking-tube contacts.

Some aspects of speech production under controlled conditions of oral anaesthesia and auditory masking

The effects of oral anaesthesia and auditory masking on various aspects of speech articulation are objectively quantified by means of the instrumental techniques of electropalatography and sound spectrography. Electropalatography is used to record details of the location and timing of tongue contacts with the palate during speech production under the different conditions of sensory deprivation. The results show that changes in speech production caused by altered tactile and auditory feedback include a general “overshooting” of target articulation (particularly of fricatives [s] and [∫]) manifested primarily by longer duration, greater area of tongue-palate contact, higher fricative frequency, and more fronted place of articulation. There was also some indication in the results that different types of sensory information may play different roles in the ongoing control of speech performance.

Relationship of Intraoral Air Pressure to Tongue Tip-Alveolar Ridge Contact for Lingual Alveolar Stops

Three male speakers were fitted with intraoral air pressure sensing tubes and strain gauge pressure transducers. The transducers were positioned behind the maxillary central incisors. Simultaneous recordings of air pressure and tongue contact were used to determine the relationship between the two during the articulation of /t/ and /d/. The speech samples were VCV utterances constructed using vowels /i/, /a/, and /u/ and words with /t/ and /d/ in the initial, midvocalic, and final positions. Comparison of the resultant curves showed the onset of intraoral air pressure build up coincided temporally with tongue contact with the alveolar ridge. The pressure rise continued until the tongue was withdrawn at which time a rapid pressure drop occurred. This precise relationship was found for all conditions of the study.

Patterns of tongue contact in normal and lisping speakers.

The accuracy of traditional articulatory descriptions of /s/ productions by normal and lisping speakers was tested. Three groups of children (normal speakers, frontal lispers, and lateral lispers) provided recordings of tongue pressures against the alveolar ridge while saying syllables containing /s/ and /z/. Two patterns of tongue contact were found for frontal lispers: one like that of normal speakers and another like that of lateral lispers. Lateral lispers uniformly provided deviant midline measure. The age of the subjects and position of the consonant in the syllable had little effect upon tongue contact and pressure. Males, however, did exhibit greater pressure. Tongue pressures during swallowing by the lisping groups were deviant from those of normal speakers.

Speech patterns of edentulous patients and morphology of the palate in relation to phonetics

T 1 n the production of speech sounds, the tongue contacts various portions of the teeth, the alveolar ridge, and the hard and soft palate. When these structures are covered or replaced by a denture, proprioceptive feedback may be changed. Therefore, phonetics may be affected by the presence of a denture. Most of the prosthodontic literature on phonetic research has been concerned with the positioning of the artificial teeth and the vertical dimension of occlusion.1-11 Little scientific study has been reported that relates the speech changes to the palatal contour of complete dentures.‘2-15 There are conflicting data on how denture wearers achieve speech improvement. AllenI stated that neglect of phonetics in complete denture construction may be attributed to the fact that edentulous patients tend to return to their normal speech patterns after insertion of dentures. The purpose of this study was to investigate ( 1) changes in the speech patterns of patients with new complete dentures before and at various times after insertion of the new dentures and (2) any relationship between speech production and the palatal contour of the denture.

Lip and Tongue Pressure Patterns during Syllable Productions

Strain-gauge transducers were placed on the lingual side of the dental ridge of the maxilla and mandible and on the labial side of the mandible. These were positioned to record contact pressures along ridges in five locations from the sides and in the midline. Lip and tongue contacts were recorded as subjects repeated VCV syllables containing /i/, /a/, /u/, and /s/. Different pressure patterns were found both between and within syllable utterances. Pressure peaks from the sides of the tongue corresponded to each phoneme while pressure peaks nearer the midline corresponded temporally with the consonant. Lip pressure peaks were related only with the consonant. Tongue tip and midline lip activity showed a definite movement away from the transducer for the entire syllable. The shape of the contact peaks were related to the vowel used in the syllable.

Dynamic palatography—A study of linguopalatal contacts during the production of selected consonant sounds

Instrumentation which records linguopalatal contacts during continuous speech was used to evaluate areas of the palate contacted by the tongue, to observe any evidence of ‛tonguedness”, and to determine if any characteristic linguopalatal temporal sequencing exists. The results showed that the lateral aspects of the palate, plus the incisive papilla, are the areas most commonly frequented by the tongue; the tongue appears to function in a bilaterally symmetrical manner during speech; and the dynamic manner in which the tongue contacts and releases the palate depends on whether an ‛initial” or a ‛final” consonant is being articulated.

Magnitude of reinforcement and consummatory behavior.

The rates at which white rats licked saline, sucrose, and saccharin solutions, respectively, were measured by cumulative recording of tongue contacts with the solution in question. The local rate of licking was constant for all solutions, but differences in the distribution of sustained periods of licking were related to the type and concentration of the fluid consumed.