Some articulatory correlates of perceptual isochrony

Given sequences of digits with temporally equidistant acoustic onsets, listeners do not perceive them as isochronous (Morton, Marcus, & Frankish, 1976). In order for the sequences to be perceptually isochronous, systematic departures from acoustic isochrony must be introduced. These acoustic departures are precisely those that talkers generate when asked to produce an isochronous sequence (Fowler, 1979), suggesting that listeners judge isochrony based on acoustic information about articulatory timing. The present experiment was an attempt to test directly whether perceptually isochronous sequences have isochronous articulatory correlates. Electromyographic potentials were recorded from the orbicularis oris muscle when speakers produced sequences of monosyllables “as if speaking in time to a metronome.” Sequences were devised so that lip-muscle activity was related to the syllable-initial consonant, the stressed vowel, or the stressed vowel and final consonant. Results indicate that isochronous muscular activity accompanies both isochronous and anisochronous acoustic signals produced under instructions to generate isochronous sequences. These results support an interpretation of the perceptual phenomenon reported by Morton et al. to the effect that listeners judge isochrony of the talker’s articulations as they are reflected in the acoustic signal.     

Cognitive task effects on hemispheric blood flow in humans: Evidence for individual differences in hemispheric activation

Evidence from two indirect measures of hemispheric activity, EEG α and conjugate lateral eye movements, has pointed to the existence of individual differences in hemispheric activation. Results from a more direct indicator of hemispheric activity, regional cerebral blood flow as measured by the ¹³³Xe inhalation method, show that such individual differences can be detected in the distribution of blood in the two hemispheres and that the amount of increase in blood flow in the right relative to the left hemisphere is correlated with performance on a spatial task. These results corroborate and extend the findings from the EEG and eye movement studies and suggest that the dimension of individual differences in hemispheric activation may exert significant influence on cognitive performance and on problem-solving strategies.     

The availability explanation of excessive plausibility assessments

The assessment of hypotheses in hypothesis generation involves a comparison between those hypotheses that have been generated (specified) and those that are not generated (unspecified). Experiment 1 was an investigation of an “availability explanation” for subjects' overconfidence in the probability of specified hypotheses. The conjecture is that subjects have difficulty retrieving unspecified hypotheses from memory. Therefore, the underpopulated set of unspecified hypotheses is assessed as less probable then it actually is and the specified set is assessed as more probable. Two manipulations to increase the availability of unspecified hypotheses were investigated. One involved explicitly requesting subjects to populate the unspecified set; the other was a computer presentation of candidate unspecified hypotheses. Results of experiment 1 were that assessment overconfidence for both experimental groups was reduced. The results support the conjecture that the availability heuristic is at least partially responsible for subjects' overconfidence. The main result of experiment 2 was that the overconfidence bias persisted with different assessment methods for both subject-generated and experimenter-supplied hypotheses.     

TEACHING THE HANDICAPPED TO EAT IN PUBLIC PLACES: ACQUISITION,GENERALIZATION AND MAINTENANCE OF RESTAURANT SKILLS

This study examined classroom-based instruction in restauranting skills for handicapped persons. Three male students were taught each of four skill components in sequential order: locating, ordering, paying, and eating and exiting. Training was implemented in a multiple baseline design across subjects and consisted of modeling and role playing in conjunction with photo slide sequences and a simulated ordering counter. The use of a menu containing general item classes and a finger matching procedure for identifying errors in the delivery of change greatly reduced the reading and math skills necessary to enter and complete the program. Periodic probes were conducted in a McDonald's restaurant prior to, during, and up to one-year following the termination of training. In addition, two probes (overt and covert observation) were conducted in a Burger King restaurant to assess further generalization to a location different from the one depicted throughout training. Results showed that students' performance on restaurant probes improved as a result of training, generalized to novel settings, maintained over an extended period of time, and was comparable to that of a normative sample of nonretarded persons.     

Performance of dyslexic children on speech perception tests

Several researchers who have compared the performance of dyslexic and normal-reading children on a variety of different tasks have suggested that dyslexic children may have subtle deficits in the phonemic analysis of spoken as well as written language. Thus it is of interest to know how children who have extraordinary difficulty learning to read can perform explicity auditory-phonetic tasks. Seventeen dyslexic children (10 years of age) and a group of 17 controls were administered tests of identification and discrimination of synthesized voiced stop consonants differing in place of articulation. These were tests of the type used to study categorical perception in adults, adapted for use with young children. Significant differences between dyslexics and controls were found in both kinds of tasks; the pattern of identification and discrimination differences suggests an inconsistency in the dyslexics' phonetic classification of auditory cues. A significant relationship was found between reading level and speech discrimination.     

Hypnosis for young adults: Freeing “the doctor who resides within”

This paper explains that the phenomenon of hypnosis is a naturally occurring talent, capacity, and skill that some practitioners suggest exists in nearly 90% of the population. Erickson's concept of and utilization of indirect suggestion is described and critiqued as an approach consistent with the separation/individuation issues confronting contemporary young adults. Hypnotherapy is recommended as a highly effective tool in a society suffering from severe alienation and lack of identity. Hypnosis is compared and contrasted with Cousin's discussion of placebo utilization in medicine. Hypnosis, akin to the placebo, is recognized as giving the doctor who resides within each patient a change to go to work.     

The air gap phenomenon in children's landscape drawings

The “air gap” phenomenon was found to be very common in the free landscape drawings of middle and later childhood. Three experiments are reported in which the contextual cues for such drawings were systematically manipulated. When subjects were supplied with drawing sheets constructed to imply the absence of the air gap, the phenomenon was eliminated in most of their drawings. When supplied with sheets constructed to imply its presence, most subjects produced air gap drawings using contextually provided reference lines. There were no consistent transfer effects across different cuing orders. The susceptibility of the air gap phenomenon to modification by task manipulation suggests that it results from problems of production rather than from defects in the child's internal representation of the world.     

Infant emotion and the vocal affect lexicon

The role of the vocal channel of emotion expression in infancy has been neglected in developmental theory. The present review describes the ontogenetic course of vocal emotional expression as exhibited by human and infrahuman primate young and considers its dynamic relationship to the facial and bodily components of expression. The infant's encoding of negative and positive emotion expression is discussed within a developmental framework. In addition, this review assesses the impact of early social influences. It is concluded that early patterns of infant vocal emotional expression are probably biogenetically determined and that there may be certain universal vocal signals. However, data derived from studies of dyadic interaction indicate that the transition from raw affect expression in early infancy to a more modulated pattern later on is a product not only of neuromuscular maturation but of maternal coaching in affective expression as well.     

Medication effects in the classroom: Three naturalistic indicators

Hyperactive and comparison boys participated in 5-week summer enrichment programs that included classroom activities and structured assessments of peer interaction patterns. During the 3rd and 4th weeks of these programs, a double-blind, methylphenidate-placebo crossover design was implemented within the hyperactive group. Three heterogeneous indicators of everyday behaviors were obtained: number of negative incidents noted by staff, quality of handwriting, and number of times the teacher called the boys' names aloud in the classroom. Medication effects emerged for each of these indicators. When hyperactive boys were taking placebos, they were involved in more negative incidents, their handwriting was poorer, and their names were called more frequently than when the boys were taking methylphenidate. Interrelationships among the measures suggest moderate cross-situational generality of medication responsiveness. Discussion focused on the bandwidth of medication effects and the need to examine the social ramifications of child treatments.This research was supported in part by NIMH grant 29475 and NIDA grant 01070. We gratefully acknowledge the participation of the data coders and the many summer school staff. Special thanks go to Mike Berlin, Barry E. Collins, and Sharon Dotemoto. Methylphenidate and placebo were supplied by Ciba-Geigy, Summit, New Jersey.