Developmental and acquired dyslexia: A comparison

Jorm (1979a) has drawn attention to similarities between developmental dyslexia and acquired deep dyslexia, an analogy which has been criticized by A. W. Ellis (1979). A series of three experiments compared the two syndromes, using the techniques applied by Patterson and Marcel (1977) to adult deep dyslexics, to study a group of 15 boys suffering from developmental dyslexia. Patterson and Marcel's patients were able to perform a lexical decision task but showed no evidence of phonemic encoding of nonwords; our dyslexic children performed this task very slowly and with reduced accuracy but showed clear evidence of phonemic coding of the nonword items. Patterson and Marcel observed that their patients could not read out orthographically regular nonwords; our dyslexic children were able to do this task, although more slowly and somewhat less accurately than their chronological age or reading age controls. Finally, Patterson and Marcel observed that highly imageable words were more likely to be read correctly than words of equal frequency but low imageability; we observed a similar effect in both our dyslexic group and in their reading age controls. This implies that the imageability effect may not be peculiar to dyslexics but may be characteristic of normal reading under certain conditions. It is concluded that developmental dyslexics differ from the patients studied by Patterson and Marcel in demonstrating a pattern of reading which, though slow, is qualitatively similar to the reading of normal readers of a younger age. As such, our results do not support Jorm's position.     

Stutterers' voice initiation times during conditions of novel stimulation

The present experiment examined stutterers' voice initiation times (VITs) during conditions of novel stimulation. The experimenters were interested in determining how VITs varied as a function of pacing and masking. Stutterers were examined in control, pacing, and masking conditions. The results indicated that: (1) stutterers significantly improved their VITs in the pacing condition as compared with the control condition (p = 0.005), (2) stutterers had significantly faster VITs in the pacing condition as compared with the masking condition (p = 0.005), and (3) stutterers improved VITs in the masking condition as compared with the control condition (p = 0.075). These results are discussed in terms of the facilatory nature of novel stimulation in modifying speech-system functioning.     

Lexical decision for open- and closed-class words: failure to replicate differential frequency sensitivity

Bradley and her colleagues (D. C. Bradley, Computational distinctions of vocabulary type, unpublished Ph.D. thesis, Massachusetts Institute of Technology, 1978D. C. Bradley, M. E. Garrett, &; E. B. Zurif, in D. Caplan (Ed.), Biological studies of mental processes, Cambridge, MA: MIT Press, 1980) have reported a marked difference in frequency sensitivity between open- and closed-class words on a lexical decision task. This effect was obtained with normal subjects, but not with Broca's aphasics. Their results have already influenced experimental and theoretical investigations of syntactic processing. However, in three lexical decision experiments with normal subjects, modeled on those of Bradley et al., we failed to find such a theoretically interesting difference between the two classes. Instead, both classes showed similar reaction time frequency sensitivity for word frequencies less than approximately 316/million (H. Kucera &; W. N. Francis, Computational analysis of present-day English, Providence, RI: Brown Univ. Press, 1967, count); above 399/million, the closed class had an almost-flat function of reaction time versus the logarithm of the frequency, while the open class may have had too few members for meaningful assessment. Because reaction time may be a nonlinear function of log frequency, and because there is relatively little overlap between the frequency ranges of the two classes, comparisons of the members of the two classes which might straddle the function's inflection point must be made with extreme caution.     

Click location in sentences: A test of the linguistic competence of seven-year-old fluent and disfluent males

Ten fluent and ten disfluent 7-yr-old males were presented simple and complex fully grammatical, anomalous and scrambled sentences. A click (35-msec 1-kHz tone burst) had been superimposed within three positions to the right or left of the major syntactic boundary in each sentence. The subjects heard the sentence, repeated the sentence, and marked on a preprinted version of the sentence where they heard the click. It was expected that children with greater language facility would more probably locate the click veridically. By the same reasoning, less complex syntactic structures should be expected to influence click placement less than more complex utterances. The following results were obtained: (a) the disfluent group gave a greater number of correct responses than the fluent group; (b) more correct responses were observed for simple sentences than for complex sentences for both groups; and (c) fewer correct responses were observed for both simple and complex grammatical sentences than for anomalous and scrambled sentence types.     

The relationship between treatment exposure times and changes in stuttering frequency during contingent stimulation

Four adult stutterers were exposed to 60 consecutive minutes of verbal contigent stimulation. In each session subjects spoke until a stuttering frequency stability criterion was met (baserate) followed by 60 min of exposure to the word wrong presented contingently upon each instance of stuttering. The data were analyzed according to changes in stuttering which occured following 20, 40, and 60 min of treatment exposure. The results revealed that stuttering frequency was reduced for all subjects during all three 20-min segments of the treatment condition. The only significant reductions in stuttering frequency, however, occured within the first 20 min of treatment.     

Fluency and eye contact as factors influencing observers' perceptions of stutterers

The purpose of this study was to determine the effects of different levels of eye contact and fluency on observers' perceptions of a speaker. One of four videotapes depicting an actor (playing the part of a supervisor) interviewing another actor (who played a subordinate) were shown to 127 college students. The four videotapes represented four different conditions comprising combinations of fluent vs nonfluent speech and normal vs low eye contact. Results indicated that these combinations of fluency and eye contact differentially influence listeners' perceptions of a speaker. Highest ratings were obtained for the fluent-normal eye-contact speaker, with lower ratings for all other conditions. In addition, it was determined that the frequency of eye contact rather than fluency was more strongly related to listeners' perceptions. The clinical implications of these findings are discussed.     

Enhancing the social skills of an unpopular girl: A social learning intervention

The use of a social learning approach to reduce the unpopularity of an 11-year-old girl, Rene, at a summer camp was studied. Two social skill deficiencies were suggested to be the cause of Rene's unpopularity by her bunk house counselors: her lack of contact with bunkhouse members during free choice times, and her negative, interfering conversational style. A multiple baseline design was used by the counselors to successively implement reinforcement contingencies on each class of social skill. Substantial improvements in performance were noted concurrent with the application of each contingency. These outcomes were maintained after reinforcement contingencies were withdrawn. Sociometric ratings of Rene's popularity by her bunkhouse mates improved after intervention. These outcomes are discussed from a social learning perspective.