Listener preferences for stuttered and syllable-timed speech production

The purpose of this study was to determine how “naive” listeners react to syllable-timed speech production. Three stutterers were videotape recorded while speaking in their usual manner and pacing their speech at 100 words per minute (wpm) and 70 wpm. Twenty-three listeners rated the speech samples as to which they preferred to hear. The results indicated generally that listeners preferred paced speech to stuttering.     

Factors affecting judgments of fluency: II. Word repetitions

Six speech samples containing varying amounts of whole-word repetitions were tape-recorded and presented to 36 male and 36 female listeners. For each sample, listeners were asked to make judgments of fluent, disfluent, and stuttered speech, and to answer the question, “Would you recommend speech therapy?” Results showed that samples containing 5% or more word repetitions were not judged fluent speech by a majority of listeners. Judgments of disfluent and stuttered speech were nearly equal for speech samples containing word repetitions from 5% to 15%. At 20%, however, the judgments of stuttered speech were found to be more likely than judgments of disfluent speech. A majority of listeners recommended clinical services for speech samples containing 5% or more word repetitions. Generally, the results indicated that (1) the presence of whole-word repetitions is not normal regardless of frequency, (2) fluent speech may not contain 5% or more word repetitions, and (3) with 20% word repetitions the judgments of stuttering may be more likely than judgments of disfluency.     

Influence of linguistic complexity,rate of presentation,and interphrase pause time on auditory-verbal comprehension of adult aphasic patients

Among the variables affecting comprehension of linguistic stimuli by aphasic subjects are syntactic complexity and processing time. Comprehension performance of 15 aphasic adults was studied while altering the rate of speech presentation and varying the pause time between the major phrases within sentences of increasing grammatical complexity.Simple Active Affirmative Declarative Sentences, Negative, and Passive sentences were presented (1) at the rate of 150 words per minute (wpm) with 1-sec interphrase pause time (IPT); (2) 150 wpm with no pauses; (3) 120 wpm with 1-sec IPT; (4) 120 wpm with no pauses added.Performance was seen to vary with increasing syntactical complexity and as a function of processing time. Greater comprehension was seen with active affirmative than negative; greater with passive affirmative than with active negative. Clinical implications are discussed. Subjects demonstrated greater comprehension when sentences were presented at slower than normal rate; addition of interphrase pause time intervals aided comprehension. Combining slower rate of presentation and IPT intervals provided greatest increase in auditory processing time and showed concomitant increase in comprehension performance.     

Perceptual study of the speech of “successfully therapeutized” stutterers

The purpose of this investigation was to determine if the fluent speech of “successfully therapeutized” stutterers and a group of partially treated stutterers was perceptually different from the fluent speech of normal speaking subjects. Tape recorded speech samples of treated stutterers were obtained from leading exponents of (1) Van Riperian, (2) metronome-conditioned speech retraining, (3) delayed auditory feedback, (4) operant conditioning, (5) precision fluency shaping, and (6) “holistic” therapy programs. All forms of disfluency were edited out of these tapes. The remaining samples were then paired with matched fluent samples of normal talkers and presented to a group of 20 sophisticated judges. The judges were instructed to select from each paired speech sample presented to them the one produced by the stuttering subject. The results of the analyses of variance for correct identification of the stutterers showed that the partially treated stutterers, as well as each group of therapeutized stutterers, were identified at levels significantly above chance. This meant that the fluent speech of the partially and successfully treated stutterers was perceptibly different from the utterances of the normal speakers sampled. In addition, the analyses of variance also revealed that all stuttering groups had a significant severity factor. This finding indicated there was a significant difference between the severity subgroup in all the samples investigated. These results were discussed in terms of their clinical implications.     

Unsophisticated judges' perceptual evaluations of the speech of “successfully treated” stutterers

The purpose of this investigation was to determine if the speech of “successfully therapeutized” stutterers and a group of partially treated stutterers was perceptually different from the speech of normal speakers when judged by unsophisticated listeners. Tape-recorded speech samples of treated stutterers were obtained from leading proponents of (1) Van Riperian, (2) metronome-conditioned speech retraining, (3) delayed auditory feedback, (4) operant conditioning, (5) precision fluency shaping, and (6) “holistic” therapy programs. Fluent speech samples from these groups of stutterers were paired with matched fluent samples of normal talkers and presented to a group of 20 unsophisticated judges. The judges were instructed to select from each paired speech sample presented to them the one produced by the stuttering subject. The results of the analyses showed that five of seven experimental groups were identified at levels significantly above chance. It can be concluded that the fluent speech of the partially and successfully treated stutterers was perceptibly different from the utterances of the normal speakers and that the perceptual disparity can be detected, even by unsophisticated listeners.     

A new measure for determining children's subjective organization of speech

A new technique for determining children's subjective organization of speech is described. The technique consists of teaching a child a sentence and then repeatedly (1) reading the sentence up to a selected point, (2) sounding a tone, and (3) having the child supply the next word. The time from the tone to the onset of the child's voice is the dependent variable. In the first study 6- and 8-year-old children memorized the following sentence: “John likes to feed the little puppies in the barn.” Their response times suggested that the dominant segmentation pattern consisted of four phrases: a subject phrase, a verb phrase, an object phrase and a modifier phrase. Within each phrase differences between reaction times were on the order of 30 msec. Across phrases they were on the order of 120 msec. The same trend emerged for subsamples of the children with various short-term memory sizes, and for adults. It also appeared for subsamples of the total scores (e.g., first six trials and last six trials). In order to provide further evidence of the technique's validity, different sentences of the same general type were presented to children with short-term memory spans of either 3, 4, or 5. As predicted, it was found that when children's spans corresponded to the number of hypothesized chunks (i.e., 4), they could repeat the sentences verbatim on the first exposure. They could not do so, however, when their spans were lower than that value or when the number of phrases was increased. It was concluded that the new technique is a promising one for assessing young children's patterns of speech segmentation.     

Effects of neutral and positive stimuli on stuttering: “Calling attention to stuttering” revisited

This study investigated the effects of presumably positive and neutral response-contingent stimuli on the occurence of stuttering. Eight adult stutterers spoke spontaneously during a 60-min experimental session, which was divided into three 20-min periods. During Condition I no stimuli were delivered. During Condition II a digital counter and a pair of yellow lights were activated each time the subject stuttered. During Condition III these same response-contingent stimuli were delivered, but with the additional factor that the subject would earn 5¢ each time the counter moved forward and the lights were illuminated. Conditions II and III were counterbalanced across subjects. The experimenter was unaware of which of the two contingencies were operative during Conditions II and III. Results showed no significant changes in occurence of stuttering due to either response-contingent stimulus. A discussion of theoretical and experimental implications is given.     

Processing the intensity of dichotic syllables

Subjects were required to match the intensity levels of the left- and right-ear members of dichotically presented nonsense syllables. When subjects matched the overall average intensities of a sequence of differing dichotic pairs no ear differences were observed. When repetitions of single dichotic pairs were matched right-ear syllables were judged louder than left-ear syllables. The results support a model predicting left-hemisphere superiority in a task permitting higher-level encoding of speech input.     

On the choice between eating and aggressive display in the Siamese fighting fish (Betta splendens)

In Expt 1, male Betta splendens were given a choice between food and a mirror image in a T-maze. All fish consistently preferred food. In Expt 2, the choice of fish that lived in the T-maze for the duration of the experiment was compared with the choice of fish that were transferred to the T-maze for each experimental session. Fish that lived in the T-maze consistently preferred food, but fish that were transferred showed a shift in preference toward mirror image. Differential inhibition of hunger and aggression by fear is suggested as the cause of the preference shift.     

Word fragmentations and repetitions in the spontaneous speech of 2–6-yr-old children

Samples of spontaneous speech of 110 nursery school children, aged 2 yr, 1 mo to 6 yr, were written down. Two of the children were regarded as stutterers by the parents and the nursery school personnel. Instances of word and phrase repetitions and word fragmentations were marked. Fragmentation of a word before the whole word is pronounced was used as criterion of stuttering. The nonstutterers had an average frequency of word repetitions of 6.3%, while word fragmentations were virtually nonoccurrent. The frequency of word repetitions decreased with increasing age. Relating word repetitions to grammatical complexity of speech, it was found that the decrease was particularly large at a certain point of the grammatical development. The two stutterers had, in addition to normal frequencies of word repetitions, marked occurences of word fragmentations (2.8 and 4.1%).     

Relation of the verbal transformation and the phonemic restoration effects

This study examined the relationship between illusory changes of repeated words (“verbal transformations” or VTs) and illusory presence of phonemes replaced by noise (“phonemic restorations” or PhRs). Separate groups of 20 subjects were each presented with one of four taped variations of the repeated stimulus word “magistrate”: stimulus intact (MAGISTRATE); speech sound “s” removed and replaced with a silent gap (MAGI TRATE); speech sound “s” removed and replaced with a louder extraneous sound (MAGI¹TRATE); syllable “gis” removed and replaced with a louder extraneous sound (MA⁷¹TRATE). The stimuli MAGI¹TRATE and MA⁷¹TRATE evoked PhRs, and with these stimuli, the phonetic changes corresponding to VTs were concentrated at the perceptually restored portions of the word. It is suggested that both PhRs and VTs are related directly to perceptual processes employed normally for the correction of errors and resolution of ambiguities in speech. Other effects of PhRs upon VTs are described and implications of these findings for mechanisms underlying speech perception are discussed.     

Parallel scanning of auditory and visual information

Two experiments involving memory retrieval of auditorilv and visually presented materials were performed. In Experiment I, subjects were presented with memory sets of 1, 2, or 4 stimuli and then with a test item to be classified as belonging or not belonging to the memory set. In Condition 1, each memory stimulus was a single, auditorily presented letter. In Condition 2, each memory stimulus was a visually presented letter. In Conditions 3 and 4, each memory stimulus was a pair of letters, one presented visually and the other auditorily. Mean reaction time (RT) for the classification task increased as a function of number of memory stimuli at equal rates for all four conditions. This was interpreted as evidence for a parallel scanning process in Conditions 3 and 4 where the auditory item and visual item of each memory stimulus pair can be scanned simultaneously. Experiment II compared memory retrieval for a simultaneous condition in which auditory and visual memory items were presented as pairs with a sequential condition in which mixed auditory-visual memory sets were presented one item at a time. RTs were shorter for the simultaneous condition. This was interpreted as evidence that parallel scanning may depend upon memory input parameters.     

Semantic priming and retrieval from lexical memory: Evidence for facilitatory and inhibitory processes

Immediately prior to each visually presented target letter string to which the subject made a speeded word-nonword classification response, a visually presented prime to which no overt response was required was shown for 360, 600, or 2,000 msec. For word (W) target trials, the priming event was either a semantically neutral warning signal (Condition NX), a word semantically related to the target word (Condition R), or a word semantically unrelated to the target word (Condition U); for nonword (N) target trials, the priming event was either the neutral warning signal (Condition NX) or a word prime (Condition WP). For the W target trials, reaction times (RTs) were slower in Condition U than in Condition NX and equally so for all three prime durations; RTs were faster in Condition R than in Condition NX and to a greater degree for the 600- and 2,000-msec prime durations than for the 360-msec prime duration. For the N targets, RTs were faster in Condition WP than in Condition NX and equally so for all prime durations. These results were interpreted within the framework of a two-factor theory of attention proposed by Posner and Snyder (1975a).     

Partial reinforcement effects and type of reward

In two experiments 68 rats were trained to bar press or run down a straight runway for food or for water under conditions of either continuous reinforcement or partial reinforcement. In both experiments, there was greater persistence of behavior which had been reinforced with food than with water. In Expt 2, the partial reinforcement extinction effect (PREE) was observed with food reward, but not with water.Within the context of the experimental procedures used, it can be concluded that the rat has mechanisms for developing persistence which are dependent on the specific motivational system involved. This conclusion is related to theories of partial reinforcement effects and to possible biological origins of the mechanisms.     

Is attention shared between the ears?

This study tests the locus of attention during selective listening for speech-like stimuli. Can processing be differentially allocated to the two ears? Two conditions were used. The simultaneous condition involved one of four randomly chosen stop-consonants being presented to one of the ears chosen at random. The sequential condition involved two intervals; in the first S listened to the right ear; in the second S listened to the left ear. One of the four consonants was presented to an attended ear during one of these intervals. Experiment I used no distracting stimuli. Experiment II utilized a distracting consonant not confusable with any of the four target consonants. This distractor was always presented to any ear not containing a target. In both experiments, simultaneous and sequential performance were essentially identical, despite the need for attention sharing between the two ears during the simultaneous condition. We conclude that selective attention does not occur during perceptual processing of speech sounds presented to the two ears. We suggest that attentive effects arise in short-term memory following processing.     

Factors affecting judgments of fluency: I. interjections

Six speech samples containing varying amounts of schwa interjections were tape-recorded and presented to 36 male and 36 female listeners. For each sample, listeners were asked to make judgments of fluent, disfluent, and stuttered speech, and to answer the question “Would you recommend speech therapy?” Results indicated that speech samples containing 5% or more interjections evoked a judgment of disfluent speech by a majority of listeners. The sample containing 20% interjections, however, was found to evoke judgments of disfluent and stuttered speech about equally. Varying numbers of listeners recommended clinical services for disfluent speech. In general, the results indicated that (1) the presence of interjections in connected speech is not normal regardless of frequency, (2) fluent speech may not contain interjections in excess of 5%, and (3) with 20% interjections in speech, the distinction between disfluency and stuttering may be blurred.     

Soft tissue anatomy of the tongue and floor of the mouth: An ultrasound demonstration

Ultrasound technology has not been used extensively in the study of normal and abnormal oral physiology and speech. Features such as soft tissue detail, real-time motion display, and subject safety make ultrasound ideal for imaging the tongue and the floor of the mouth. This study demonstrates visualization of the muscles of the tongue and floor of the mouth for a normal subject using ultrasound imaging. By employing submandibular transducer placement of real-time sector scanners, tongue anatomy and motion were continuously visualized in sagittal or coronal planes. In addition to the entire tongue surface, much of the intrinsic anatomy was identified including: the genioglossus, geniohyoid, mylohyoid, and digastric muscles; fascial boundaries such as the median fibrous septum, floor intermuscular septum, and paramedian septums; and the hyoid bone. A tongue excised from a human cadaver was scanned using ultrasound and dissected to confirm the anatomy seen in the live tongue. Tongue surface shape and configuration of the intrinsic tissue structures were observed and compared for the phonemes /k/, /u/, and /i/. Anatomical landmarks in the resting and speaking tongue are discussed as well as applications in the fields of speech science and speech pathology.     

Sudden onset of excessive repetitions in the speech of a patient with multiple sclerosis: A case report

This report provides a detailed analysis of excessive part- and whole-word repetitions in the speech of a 36-year-old male patient hospitalized for treatment of multiple sclerosis (MS) who also exhibited concurrent language and prosodic disturbances. Shortly following his hospitalization, a magnetic resonance imaging examination revealed plaques in the white matter of the medulla, cerebellum, basal ganglion, and periventricular white matter. His speech strongly resembled apractic speech patterns, chiefly syllable segregation. The source of data collected for this study was seven tape-recorded speech samples containing 2536 words spoken in 32.75 min, diagnostic reports, and clinical notes of 27 biweekly speech therapy sessions across a 5-month period. This report focused on an analysis of variables associated with the patient's part- and whole-word repetitions, and it was concluded that they were used as a compensatory device to procure additional time to articulate complex syllables. A brief critique of the therapeutic procedures used for treating his speech problem is also presented.

Educational objectives: The reader will learn about and be able to describe (1) the effects of MS on speech and language; (2) the kinds of data that were gathered to account for this patient's sudden onset of speech and language disorders; and (3) the findings that led them to conclude that his excessive repetitions were compensatory behaviors.