Reaction-time measures of stutterers and nonstutterers

Ten adult male stutterers and ten adult male nonstutterers participated in six reaction-time tasks designed to measure manual, acoustic, and laryngeal-region response latencies. The analysis revealed statistically significant differences between the groups for the acoustic data only. The results indicated that acoustic reaction-time differences are not accounted for by the speed of the general laryngeal response.     

Sources of error in the psychoeducational diagnosis of children

A detailed exploration of the role of diagnostic practices is presented, with special attention given to such practices in school psychology. Basic principles related to diagnostic typology and concepts of reliability and validity are reviewed in the context of recent diagnostic decision-making research. Finally, the intrusion and eventual reduction of particular errors of consistency and inconsistency and psychodiagnosis are examined with a view toward improvements in future training and practice.     

Cluster analysis in school psychology: An example

This investigation demonstrates the use of Ward's method of cluster analysis to uncover the underlying classification structure in a group of children (N = 200) referred for psychological evaluations by their public school teachers. Data were acquired on children's intellectual development, academic achievement, and social adjustment. The cluster solution identifies six groups of children which are statistically distinct. All three measurement areas are important in distinguishing among the different groups. The six-group solution accounted for appreciable amounts (95%) of the variability in the three measurement areas. Implications for psychologists working in the schools are discussed.     

Intelligence and teachers' ratings as predictors of abstract and concrete learning

This study concerned the prediction of children's learning with an individual measure of intelligence and teachers' evaluations. Eight abstract and eight concrete nouns were paired with nonsense geometric figures and presented to 60 elementary school children in a three-trial paired-associate (PA) learning task. Subjects' IQ scores on the Wechsler Intelligence Scale for Children-Revised and teachers' ratings of learning proficiency were used to predict children's performance on the PA task. Multiple correlations favored abstract learning with verbal scale intelligence, accounting for the majority of the variability. Teachers' ratings provided a surprising degree of predictive efficiency for abstract recall which was redundant with verbal intelligence.     

Reaction time for voiced and whispered /a/ in stutterers and nonstutterers

Recent research reviewed in this article suggests that stutterers' inability to initiate phonation promptly could be a significant factor in the occurence of stuttering. Since stuttering is either completely absent or markedly reduced in frequency during whisper, the present study tested the hypothesis that stutterers do not significantly differ from nonstutterers in reaction time (RT) for the initiation of whispered/a/, whereas the two groups differ significantly in RT for the initiation of voiced /a/. Ten adult stutterers and an equal number of comparable nonstutterers produced prolonged versions of the vowel /a/ using voice and whisper in response to tone stimuli. The results showed that stutteres and nonstutterers did not differ in RT for either voiced or whispered /a/. The stutterers, however, exhibited significantly longer RT to produce voiced /a/ than whispered /a/.     

Teacher attitudes toward stuttering

Attitudes of 100 elementary school teachers toward stuttering were studied using the Teacher Attitudes Toward Stuttering (TATS) Inventory. Teacher attitudes, as indicated by TATS Inventory scores, were compared with teacher knowledge of stuttering, age of teacher, number of years teaching experience, educational level, and whether the teacher had personal experience with a stutterer. Results indicated that significant positive correlations existed between teacher attitudes toward and knowledge of stuttering. Significant negative correlations were demonstrated between teacher attitudes/knowledge of stuttering and the presence of a stuttering child in the classroom. The applicability of the TATS Inventory as a clinical instrument in its current form and the research needed to enhance its flexibility are discussed.     

A shortened version of the Southern Illinois university speech situation checklist for the identification of speech-related anxiety

This study investigated the ability of the 51-item Southern Illinois University Speech Situation Checklist (SSC) to differentiate stutterers known to have high levels of speech-related anxiety from nonstutterers with normal levels of speech- related anxiety. Checklist responses of 65 randomly selected subjects (33 stutterers and 32 nonstutterers) were subjected to a stepwise discriminant analysis. The analysis identified a combination of 21 SSC items that had significant discriminative power. Subsequently, the derived discriminant equation achieved 93% accuracy in correctly classifying a hold-out sample of 29 subjects (14 stutterers and 15 nonstutterers). These results strongly suggest that the 21 items of the SSC identified by discriminant analysis may provide an effective screening device for identifying disfluent speakers who experience an abnormal amount of speech-related anxiety.     

The modification of intelligence through early experience

Infants judged to be at risk for subnormal intellectual growth were randomly assigned to an Experimental (N = 27) or a Control (N = 25) group. Infants in both groups received medical care and dietary supplements; their families received social work services on a request basis. Experimental children participated in an educational daycare program beginning before the third month of life. The daycare program was composed, in part, of curriculum activities designed to stimulate intellectual growth. Between 6 and 36 months of age, Experimental children maintained normal intellectual growth; Control children declined in IQ beginning between 12 and 18 months of age and remained significantly lower than Experimental children at 24 and 36 months. The mother-child IQ correlation for Control dyads was 43; for Experimental dyads the correlation was ?.05. These two types of evidence are interpreted as support for the importance of early environments in the development of intelligence.