PubMed Health⌕ Search

Biomedical subjects

R J Ingham

Publications and source records attributed to R J Ingham.

At least 37 records · Page 2Linked to original sources

Time-interval measurement of stuttering: establishing and modifying judgment accuracy.

The purpose of this study was to determine whether accuracy training for interval judgments of stuttering might generalize to increased accuracy and/or interjudge agreement for intervals other than those used during training. Ten upper-division speech-language pathology students judged 5-s audiovisually recorded speech intervals as stuttered or nonstuttered in a series of group and single-subject experiments. Judgment accuracy was determined with respect to judgments provided previously by 10 recognized authorities on stuttering and its treatment. Training occurred within single-subject experiments that used multiple baselines across speakers and repeated generalization probes to assess training effects. Results showed that judgment accuracy tended to increase after training for speakers used during the training process as well as for unfamiliar speakers. Results also replicated previous findings of slight increases in interjudge and intrajudge agreement after interval-judgment training. The implications of these results for developing a valid and reliable stuttering measurement system are discussed.

Female↗

Functional-lesion investigation of developmental stuttering with positron emission tomography.

Positron emission tomographic (PET) H2(15)O measurements of resting-state regional cerebral blood flow (CBF) were obtained in 29 right-handed men, 10 of whom stuttered and 19 of whom did not. PET images were analyzed by sampling 74 regions of interest (ROIs), 37 per hemisphere. ROI placement was guided both physiologically and anatomically. Physiological ROI placement was based on speech motor activations. Anatomical ROIs were positioned by reference to a stereotactic, neurosurgical atlas with positions confirmed and finely adjusted by co-registered magnetic-resonance images (MRIs). For all subjects, PET and MR images were normal to visual inspection. Highly significant (p < 0.0001) between-region and between-hemisphere effects were found for both groups, as have been previously reported for normal subjects, but no significant between-group differences were found for any regional CBF values. Analysis by a laterality index found a weakly significant between-groups effect (p = 0.04) that was isolated to five regions, four of which are implicated in speech or hearing. However, these regional laterality effects showed no consistent directionality, nor did these regions have absolute differences in regional blood flow between groups. Present findings do not support recent suggestions that developmental stuttering is associated with abnormalities of brain blood flow at rest. Rather, our findings indicate an essentially normal functional brain terrain with a small number of minor differences in hemispheric symmetry.

Adult↗

Judgments of stuttered and nonstuttered intervals by recognized authorities in stuttering research.

The study reported in this paper gathered judgments of stuttering on brief (5.0-sec) audiovisual speech samples taken from six adults who stuttered. Judgments were made by 10 highly experienced authorities on stuttering treatment and research, located in seven different universities or clinical research centers. Results showed considerable agreement between pairs of judges working in the same center, but large and potentially fundamental differences were identified in the amount of stuttering recorded in different centers. Approximately 40% of the 5.0-sec speech intervals used in this study were assigned the same judgment, either Stuttered or Nonstuttered, by all judges on two judgment occasions. The possibility that these intervals may serve as a core for establishing an across-center standard for behavioral judgments of stuttering is discussed.

Female↗

Identifying the onset and offset of stuttering events.

This study was designed to investigate the apparent contradiction between recent reports of physiological and interpersonal research on stuttering that claim or imply high agreement levels, and studies of stuttering judgment agreement itself that report much lower agreement levels. Four experienced stuttering researchers in one university department used laser videodisks of spontaneous speech, from persons whose stuttering could be described as mild to severe, to locate the precise onset and offset of individual stuttering events. Results showed a series of interjudge disagreements that raise serious questions about the reliability and validity of stuttering event onset and offset judgments. These results highlight the potentially poor reliability of a measurement procedure that is currently widespread in stuttering research. At the same time, they have isolated some few highly agreed stuttering events that might serve as the basis for the further development of either event-based or interval-based judgment procedures.

Female↗

Stuttering includes both within-word and between-word disfluencies.

A growing practice divides stuttered disfluencies from normal disfluencies by defining the former as "within-word" and the latter as "between-word." After reviewing the available logical and empirical evidence, this note concludes that the unstated implications of a strong form of this definition (that no between-word disfluencies are stuttering and that all within-word disfluencies are stuttering) cannot currently be supported. A weaker form of this definition might prove useful for the definition and measurement of stuttering, but only if such a definition can be both internally consistent and consistent with available clinical and empirical information.

Humans↗

Activation and serine phosphorylation of the p56lck protein tyrosine kinase in response to antigen receptor cross-linking in B lymphocytes.

We show that cross-linking the B cell AgR with anti-Ig Abs activates p56lck (Lck) in both the immature B cell line WEHI-231 and mature resting B cells from mouse spleen. Anti-Ig-stimulated Lck activity peaked after 1 to 2 min, but remained elevated for at least 15 min. Consistent with the proposed role for src family tyrosine kinases in AgR signaling, we found that Lck could phosphorylate the cytoplasmic tails of the Ig-alpha and Ig-beta components of the B cell AgR in vitro. Lck phosphorylated both of the tyrosines in the Ig-beta AgR homology motif and one of the two tyrosines in the Ig-alpha AgR homology motif. Finally, we show that AgR ligation in B cells caused a significant portion of the Lck to migrate with an apparent molecular mass of 60 kDa on SDS-PAGE gels. Conversion of p56lck to p60lck was maximal at 5 to 15 min, at which times Lck activity in the cells was decreasing. This Lck "band shift" has been observed previously in activated T cells and correlates with phosphorylation of Lck at serine 59. We show that the 60-kDa form of Lck induced by AgR cross-linking in B cells is also phosphorylated at serine 59. Phosphorylation of Lck at this site in vitro decreases its activity. Thus, in B cells, AgR cross-linking activates Lck and subsequently activates a kinase that phosphorylates Lck at serine 59, a potential negative regulatory site.

Amino Acid Sequence↗

Stutterers' self-ratings of how natural speech sounds and feels.

The efficacy of stuttering treatment has been a contentious issue in recent years. Two issues of primary concern include the treated stutterer's abnormal speech quality and the problem of continually self-monitoring fluency skills. One approach to addressing these issues is to obtain stutterers' self-ratings of speech quality and levels of speech monitoring. However, the reliability and validity of such self-ratings need to be assessed before they are suitable for use in stuttering treatment. The present study investigated one method of estimating the reliability and validity of stutterers' self-ratings of how natural their speech sounds (speech naturalness), and how natural they feel about the amount of attention they are paying to the way they are speaking (feel naturalness). Twelve adult stutterers were instructed to self-rate the speech and feel naturalness of their speech under a variety of rhythmic stimulation conditions across repeated rating occasions. With some qualifications, the results showed that stutterers were relatively consistent and valid self-raters of speech quality and levels of speech monitoring.

Adult↗

Time-interval measurement of stuttering: effects of interval duration.

The study reported in this article used a binary forced-choice judgment procedure to investigate the effects of sample duration on observers' judgements of stuttering. Two groups of judges, differing in their previous experience with stuttering, categorized 270 speech intervals as stuttered or nonstuttered; the intervals were drawn from 30 persons who stuttered and ranged from 1 sec to 15 sec in duration. Results showed that judgments were consistently related to interval duration, with shorter intervals significantly more likely than longer intervals to be labeled nonstuttered. Interjudge agreement levels, however, were largely unaffected by the different interval durations for most speakers and for both judge groups, with the exception of the longest and shortest intervals drawn from speakers evidencing the mildest and most severe stuttering. An interval duration in the 3- to 5-sec region appeared to attract the most satisfactory level of agreement. The implications of these findings for interval-based clinical and experimental measurements of stuttering are discussed.

Adolescent↗

Time-interval measurement of stuttering: effects of training with highly agreed or poorly agreed exemplars.

This study required six groups of judges, three experimental groups and three control groups (all n = 5), to categorize consecutive 5.0-sec speech intervals as Stuttered or Nonstuttered on four judgment occasions. Between the second and third occasions, each experimental group was trained to categorize correctly one of three sets of speech intervals: agreed intervals, which had been unanimously prejudged to be Stuttered or Nonstuttered; disagreed intervals, which had been prejudged to be Stuttered by approximately half of a large group of judges; or randomly selected intervals, including both agreed and disagreed intervals. Results replicated and extended an earlier finding of improved interjudge agreement for judges trained with highly agreed intervals (Ingham, Cordes, & Gow, 1993): Training with highly agreed intervals was shown to be more effective than equivalent exposure to those intervals without feedback, and training with highly agreed intervals was shown to be more effective than training with, or exposure to, poorly agreed or randomly selected intervals.

Female↗

The reliability of observational data: II. Issues in the identification and measurement of stuttering events.

Much attention has been directed recently toward the problem of measuring occurrences of stuttering with satisfactory levels of interjudge agreement. This paper reviews the prominent concepts of the stuttering event, arguing that they may be one cause of the stuttering measurement problem. The evidence that has led to concerns about the reliability of stuttering event measurements is also reviewed. Reliability and measurement issues that were discussed in the first paper of this series (Cordes, 1994) emerge as basic to the interpretation of much stuttering research, and it is argued that the stuttering measurement problem is not confined to research on stuttering judgments but actually permeates other important stuttering research areas. Some recent attempts to resolve the stuttering measurement problem are reviewed, and the implications of developing an improved measurement system for this disorder are discussed.

Humans↗

Time-interval measurement of stuttering: modifying interjudge agreement.

This paper reports the results of two experiments that investigated interval-by-interval inter- and intrajudge agreement for stuttered and nonstuttered speech intervals (4.0 sec). The first experiment demonstrated that interval-by-interval interjudge agreement could be significantly improved, and to satisfactory levels, by training judges to discriminate between experimenter-agreed intervals of stuttered and nonstuttered speech. The findings also showed that, independent of training, judges with relatively high intrajudge agreement also showed relatively higher interjudge agreement. The second experiment showed that interval-by-interval interjudge agreement was not significantly different if judges rated 4-sec speech intervals from different samples under three conditions: in random order, separated by 5-sec recording intervals; in correct order, also separated by 5-sec recording intervals; or after brief judgment signals that occurred every 4 sec during continuous samples. The implications of these findings for stuttering measurement are discussed.

Adult↗

Time-interval measurement of stuttering: systematic replication of Ingham, Cordes, and Gow (1993).

The study reported in this paper was designed to replicate and extend the results of an earlier study (Ingham, Cordes, & Gow, 1993) that investigated time-interval judgments of stuttering. Results confirmed earlier findings that interjudge agreement is higher for these interval-recording tasks than has been previously reported for event-based analyses of stuttering judgments or for time-interval analyses of event judgments. Results also confirmed an earlier finding that judges with intrajudge agreement levels of 90% or better show higher interjudge agreement than judges with lower intrajudge agreement scores. This study failed to find differences between audiovisual and audio-only judgment conditions; between relatively experienced and relatively inexperienced student judges; and, most importantly, between the judgments made, and the agreement levels achieved, by judges from two different clinical research settings. The implications of these findings for attempts to develop a reliable measurement method for stuttering are discussed.

Adult↗

Time-interval analysis of interjudge and intrajudge agreement for stuttering event judgments.

In response to the recognized need for a valid and reliable way to measure stuttering, this study investigates a measurement methodology based on time-interval analyses of stuttering event judgments. Three groups of judges, differing in stuttering judgment experience, identified stuttering events in 12 repeated presentations of five 1-min speech samples. Fixed time intervals ranging from 0.2 sec to 7.0 sec were then superimposed on the event judgments by a data analysis program. Inter- and intrajudge interval-by-interval agreement, and agreement for total numbers of intervals containing stuttering event judgments, were calculated for each judge group. Results showed that agreement was superior among more experienced judges and in longer interval lengths. Agreement varied across speech samples but not across the repeated judgment opportunities. Agreement was maximized at greater than chance levels for an interval of approximately 3.0 sec, but even this best agreement did not exceed a mean of approximately 60% for experienced judges.

Adolescent↗

Modifying electroglottograph-identified intervals of phonation: the effect on stuttering.

Single-subject experiments were conducted with an adolescent and an adult male who stutter to assess the effect on stuttering of changing the frequency of phonation intervals that were within prescribed duration ranges during spontaneous speech. Electroglottograph-identified intervals of phonation were measured using a computer-assisted biofeedback system. Both subjects demonstrated that their stuttering could be controlled by modifying the frequency of phonation intervals within short duration ranges. The experimental effects not only replicated earlier findings but were demonstrated to be independent of changes in speaking rate, or alterations to other intervals of phonation, and produced little disruption to speech naturalness. The theoretic implications of these findings are discussed.

Adult↗

On valid and reliable identification of normal disfluencies and stuttering disfluencies: a response to Aram, Meyers, and Ekelman (1990)

Aram, Meyers, and Ekelman (1990, Brain and Language, 38, 105-121) recently reported finding that children with unilateral brain lesions produced more stuttering-type nonfluencies than their neurologically normal peers. However, they did not report inter- or intrajudge agreement for the nonfluency types or for their method of measuring speech rate. The speech rates they reported were also unusually fast. We argue that these problems with Aram et al.'s study imperil both their results and their conclusions regarding developmental stuttering.

Brain Damage, Chronic↗