An fMRI study of temporal sequencing of motor regulation guided by an auditory cue—a comparison with visual guidance

The neuronal system to process and transfer auditory information to the higher motor areas was investigated using fMRI. Two different types of internal modulation of auditory pacing (1 Hz) were combined to design a 2×2 condition experiment, and the activation was compared with that under a visual guidance. The bilateral anterior portion of the BA22 (ant-BA22) and the left BA41/42 were more extensively activated by the combined modulation condition under the auditory cue than that under the visual cue. Among the four auditory conditions with or without the two types of internal modulation, the activation in the ant-BA22 was augmented only on the left side by the combined modulation condition. The left ant-BA22 may be especially involved in integrating the external auditory cue with internal modulation, while the activation on the right side did not depend on the complexity. The role of the left BA41/42 in motor regulation may be more specific to the processing of an auditory cue than that on the right side. These two areas in the left temporal lobe may be organized as a subsystem to handle the timing of complex movements under auditory cues, while the higher motor areas in the frontal lobe support both sensory modalities for the cue. This architecture may be considered as ‘audio-motor control’, which is similar to the visuo-motor control of the front-parietal network.     

Verbal Abilities in Low and Highly Proficient Bilinguals

The study investigated native language verbal skills among low and highly proficient bilinguals, using the WISC III verbal subtests. Highly proficient bilinguals showed a superiority for almost all verbal subtests. This finding lends support to Threshold Theory which maintains that bilinguals need to achieve high levels of linguistic proficiency before bilingualism can promote cognitive development. Our study also shows that verbal ability underlying proficiency in the native language can be generalized to a foreign language, revealing a causal connection between native and foreign language learning.     

Grammatical language impairment and the specificity of cognitive domains: relations between auditory and language abilities

Grammatical-specific language impairment (G-SLI) in children, arguably, provides evidence for the existence of a specialised grammatical sub-system in the brain, necessary for normal language development. Some researchers challenge this, claiming that domain-general, low-level auditory deficits, particular to rapid processing, cause phonological deficits and thereby SLI. We investigate this possibility by testing the auditory discrimination abilities of G-SLI children for speech and non-speech sounds, at varying presentation rates, and controlling for the effects of age and language on performance. For non-speech formant transitions, 69% of the G-SLI children showed normal auditory processing, whereas for the same acoustic information in speech, only 31% did so. For rapidly presented tones, 46% of the G-SLI children performed normally. Auditory performance with speech and non-speech sounds differentiated the G-SLI children from their age-matched controls, whereas speed of processing did not. The G-SLI children evinced no relationship between their auditory and phonological/grammatical abilities. We found no consistent evidence that a deficit in processing rapid acoustic information causes or maintains G-SLI. The findings, from at least those G-SLI children who do not exhibit any auditory deficits, provide further evidence supporting the existence of a primary domain-specific deficit underlying G-SLI.     

Functional analysis and treatment of verbal perseverations displayed by an adult with autism

The function of perseverative speech for an adult man who had been diagnosed with autism and mental retardation was examined. Results showed that verbal perseverations were maintained by social attention. An intervention consisting of differential reinforcement of appropriate verbal responses and extinction of perseverative verbal responding was effective in decreasing verbal perseverations.     

Social antecedents of children's eyewtness testimony a single-subject experimental analysis

In a laboratory simulation, a single-subject design was used to examine the effects of two types of social influence on children's eyewitness testimony, which has not been the subject of systematic behavioral analyses. This study replicates and extends findings from group-comparison studies, and shows that a topic of pressing social importance is amenable to analysis at the individual level, and therefore, potentially, to a behavioral analysis.     

The role of specific consequences in the maintenance of three types of questions

This research replicated and extended a study by Williams, Donley, and Keller (2000). In that study, children with autism received a box with an object inside and learned to ask “What's that?,” “Can I see it?,” and “Can I have it?” to have the name of the object, to see the object, and to get the object, respectively. The purpose of the present research was to determine if the three questions (a) were three independent repertoires of behavior, (b) constituted three instances of a single functional response class, or (c) belonged to a chain of behavior. The 3 boys with autism who participated responded independently to each question when the consequences for each question were altered. This indicates that the three target responses were three independent repertoires of behavior, each one reinforced and maintained with its specific consequences. Thus, this procedure serves to teach children with autism to ask questions with flexibility according to a variable context.     

Regulation of glutamate synapses by nicotinic acetylcholine receptors in auditory cortex

Acetylcholine plays an important role in regulating the processing of sensory stimuli, and understanding its specific cellular actions is critical to understanding how sensory cortex develops and functions in different behavioral states. Here we review recent work on the cellular effects of nicotinic receptor activation in auditory cortex and describe how these actions could affect systems-level auditory function. In particular, we describe a novel function of nicotinic acetylcholine receptors to regulate glutamate synapses containing N-methyl-D-aspartate receptors during early postnatal development. The transient regulation of developing glutamate synapses also defines a window of vulnerability during which exposure to exogenous nicotine disrupts synapse development. Thus, it appears that nicotinic regulation of glutamate synapses is a critical feature of auditory cortex development.     

THE EFFECTS OF THE QUESTION “WHAT IS THIS?” ON TACT-TRAINING OUTCOMES OF CHILDREN WITH AUTISM

Tact training is a common element of many habilitative programs for individuals with developmental disabilities. A commonly recommended practice is to include a supplemental question (e.g., “What is this?”) during training trials for tacts of objects. However, the supplemental question is not a defining feature of the tact relation, and prior research suggests that its inclusion might sometimes impede tact acquisition. The present study compared tact training with and without the supplemental question in terms of acquisition and maintenance. Two of 4 children with autism acquired tacts more efficiently in the object-only condition; the remaining 2 children acquired tacts more efficiently in the object + question condition. During maintenance tests in the absence of the supplemental question, all participants emitted tacts at end-of-training levels across conditions with no differential effect observed between training conditions.Key words: autism, language training, stimulus control, tacts, verbal behaviorSkinner (1957) defined the tact as a response “evoked by a particular object or event or property of an object or event” (p. 82) and considered it to be one of the most important verbal operants. Tacts are maintained by generalized social reinforcement and, thus, they are central to many social interactions. For example, the tact “That cloud looks like a horse” (under the control of a visual stimulus) could evoke a short verbal interaction about the sky or horses. The tact “My tummy hurts” (under the control of an interoceptive stimulus) could evoke soothing statements from a parent. A child who tacts “doggie” in the presence of a cat likely would evoke a correction statement from an adult, further refining two stimulus classes (i.e., dog and cat). These examples illustrate that, despite their topographical differences, the tact relations share antecedent control by a nonverbal discriminative stimulus (S^D) and are maintained by generalized social reinforcement.In habilitative programs for individuals with language impairments, autism, and intellectual disabilities, tacts often are taught for objects (e.g., ball), object features (e.g., color, size, shape), activities (e.g., jumping), prepositions (e.g., between), and emotions (e.g., sad) among others. Although conceptualized differently among therapeutic approaches, the tact relation occupies a central position in many early-intervention curricula. For example, Lovaas (2003) and Leaf and McEachin (1999) describe these relations as expressive labels and recommend that they be taught early in language training using three-dimensional objects accompanied by the supplemental questions “What is it?” or “What''s this?” Alternatively, Sundberg and Partington (1998) explicitly refer to the relation as a tact and recommend beginning instruction by including the question “What is it?” before eventually fading the question. In addition to these clinical manuals, the use of supplemental questions during tact training has appeared in some empirical studies on tact or expressive-label training (e.g., Braam & Sundberg, 1991; Coleman & Stedman, 1974), but not others (e.g., Williams & Greer, 1993). Regardless of whether tact training initially includes supplemental questions prior to response opportunities, tacts ultimately should be emitted readily under the sole control of the nonverbal S^D as well as when it happens to be accompanied by a question.Conceptually, at least four potential problems could arise from introducing supplemental questions early and consistently in tact training. First, the acquired responses might not be emitted unless the question is posed (i.e., prompt dependence). This problem would lead to few spontaneous tacts occurring outside the explicit stimulus control of the training environment. Williams and Greer (1993) compared comprehensive language training conducted under the stimulus control specified in Skinner''s (1957) taxonomy of verbal behavior to a more traditional psycholinguistic perspective with supplemental questions and instructions embedded within trials. For all three adolescents with developmental disabilities, the targets taught from the verbal behavior perspective were maintained better in natural contexts than those taught from the psycholinguistic perspective. However, because data were not reported for each individual verbal operant, it is unclear what specific impact their tact-training procedures had on the outcomes.The second potential problem is that the supplemental question might acquire intraverbal control over early responses and interfere with the acquisition of subsequent tact targets. For example, Partington, Sundberg, Newhouse, and Spengler (1994) showed that the tact repertoire of a child with autism had been hindered by prior instruction during which she was asked “What is this?” while being shown an object. The supplemental question subsequently evoked previously acquired responses and blocked the ability of new nonverbal S^Ds (i.e., objects) to evoke new responses. Partington et al. then showed that new tacts were acquired by eliminating the supplemental question from instructional trials.The third potential problem is that learners might imitate part of or the entire supplemental question prior to emitting the target response (e.g., “What is it” → “What is it … ball.”). For example, Coleman and Stedman (1974) demonstrated that a 10-year-old girl with autism imitated the question “What is this?” while being taught to label stimuli depicted in color photographs. Such an outcome results in a socially awkward tact repertoire and requires additional intervention to remedy the problem.Finally, including supplemental questions during tact training might impede skill acquisition, perhaps via a combination of the problems described earlier. Sundberg, Endicott, and Eigenheer (2000) taught sign tacts to two young children with autism who had prior difficulty acquiring tacts. In one condition, the experimenter held up an object and asked, “What is that?” In the comparison condition, the experimenter intraverbally prompted the participant to “sign [object name]” in the presence of the object. Sundberg et al. demonstrated substantially more efficient tact acquisition under the sign-prompt condition than when the question “What is that?” was included in trials; the latter condition sometimes failed to produce mastery-level responding.Teaching an entire tact repertoire while including supplemental questions (e.g., “What is it?”) during training trials could produce a learner who is able to talk about his or her environment only when asked to do so with similar questions. To the extent that this is not a therapist''s clinical goal, teaching the tact under its proper controlling variables may eliminate such problems. Of course, inclusion of supplemental questions during the early phases of language training could be faded over time such that the target tact relation is left intact prior to the end of training (Sundberg & Partington, 1998). However, the aforementioned studies have documented problems with using supplemental questions during tact training. Given the ubiquity of tact training in habilitation programs, the numerous problems that may arise when supplemental questions are included in training trials, and the limited research on the topic, further investigation is warranted. Thus, the purpose of the present study was to compare directly the rate of acquisition and subsequent maintenance of tacts taught using only a nonverbal S^D (i.e., object only) with tacts taught using a question (“What is this?”) in conjunction with the nonverbal S^D (i.e., object + question). The present study extends earlier research by examining both acquisition and maintenance and by including individuals with no prior history of formal tact training.