Effects of music on vocal stereotypy in children with autism

We examined the effects of manipulating the intensity (i.e., volume) of music on engagement in vocal stereotypy in 2 children with autism. Noncontingent access to music decreased immediate engagement in vocal stereotypy for each participant, but it produced only marginal effects on subsequent engagement in the behavior (i.e., after withdrawal). Manipulating the intensity of music did not produce differential effects on immediate engagement in vocal stereotypy. The implications of the results and applications for future research are discussed.     

The effects of verbal operant training and response interruption and redirection on appropriate and inappropriate vocalizations

Past research has shown that response interruption and redirection (RIRD) can effectively decrease automatically reinforced motor behavior (Hagopian & Adelinis, 2001). Ahearn, Clark, MacDonald, and Chung (2007) found that a procedural adaptation of RIRD reduced vocal stereotypy and increased appropriate vocalizations for some children, although appropriate vocalizations were not targeted directly. The purpose of the current study was to examine the effects of directly targeting appropriate language (i.e., verbal operant training) on vocal stereotypy and appropriate speech in 3 children with an autism spectrum disorder. The effects of verbal operant (i.e., tact) training were evaluated in a nonconcurrent multiple baseline design across participants. In addition, RIRD was implemented with 2 of the 3 participants to further decrease levels of vocal stereotypy. Verbal operant training alone produced slightly lower levels of stereotypy and increased appropriate vocalizations for all 3 participants; however, RIRD was required to produce acceptably low levels of stereotypy for 2 of the 3 participants.     

Dual-task automatization: The key role of sensory–motor modality compatibility

How do people automatize their dual-task performance through bottleneck bypassing (i.e., accomplish parallel processing of the central stages of two tasks)? In the present work we addressed this question, evaluating the impact of sensory–motor modality compatibility—the similarity in modality between the stimulus and the consequences of the response. We hypothesized that incompatible sensory–motor modalities (e.g., visual–vocal) create conflicts within modality-specific working memory subsystems, and therefore predicted that tasks producing such conflicts would be performed less automatically after practice. To probe for automaticity, we used a transfer psychological refractory period (PRP) procedure: Participants were first trained on a visual task (Exp. 1) or an auditory task (Exp. 2) by itself, which was later presented as Task 2, along with an unpracticed Task 1. The Task 1–Task 2 sensory–motor modality pairings were either compatible (visual–manual and auditory–vocal) or incompatible (visual–vocal and auditory–manual). In both experiments we found converging indicators of bottleneck bypassing (small dual-task interference and a high rate of response reversals) for compatible sensory–motor modalities, but indicators of bottlenecking (large dual-task interference and few response reversals) for incompatible sensory–motor modalities. Relatedly, the proportion of individuals able to bypass the bottleneck was high for compatible modalities but very low for incompatible modalities. We propose that dual-task automatization is within reach when the tasks rely on codes that do not compete within a working memory subsystem.

     

Abatement of intractable vocal stereotypy using an overcorrection procedure

We conducted a series of reversals to compare the effects of four different treatments on vocal stereotypy emitted by a 7‐year‐old boy with autism. The results showed that (1) the level of vocal stereotypy decreased during exposure to matched stimulation but returned to high levels immediately upon its removal; (2) stereotypy did not significantly decrease during differential reinforcement of other behavior; and (3) contingent withdrawal of movies and music (i.e., response cost) was only moderately effective. However, positive practice overcorrection decreased vocal stereotypy by clinically significant levels. Further, when differential reinforcement of engagement in a Lego^® building task was implemented, the level of engagement was significantly higher when positive practice overcorrection was in place than when overcorrection was withdrawn. Copyright © 2011 John Wiley & Sons, Ltd.     

A STIMULUS CONTROL PROCEDURE TO DECREASE MOTOR AND VOCAL STEREOTYPY

A changing criterion design was used to examine the effects of two stimuli (a green card and a red card), conditioned via discrimination training, on reducing motor and vocal stereotypy in a youngster with autism while he looked at books. During discrimination training, motor and vocal stereotypy was not interrupted in the presence of a green stimulus, but was interrupted in the presence of a red stimulus using manual guidance and appropriate behavior was reinforced. After the participant demonstrated successful discrimination of the stimuli (i.e., the absence of stereotypy in the presence of a red stimulus and the engagement in stereotypy in the presence of a green stimulus), intervention began. During intervention, upon meeting criterion for latency to engage in motor and vocal stereotypy in the presence of the red stimulus for a target duration, the participant was provided access to the green stimulus, which signaled that motor and vocal stereotypy would not be interrupted. The criterion latency to engage in stereotypy in the presence of the red stimulus was systematically increased. Simultaneously, the duration of access to the green stimulus was systematically decreased. The red and green stimuli were faded from poster boards to colored 10 × 10 cm cards, and stimulus control was generalized to the participant's classroom and to a community setting (i.e., public library). Results are discussed in terms of discrimination training as a useful intervention for reducing motor and vocal stereotypy. Copyright © 2011 John Wiley & Sons, Ltd.     

The sensorimotor contributions to implicit memory, familiarity, and recollection

The sensorimotor contributions to memory for prior occurrence were investigated. Previous research has shown that both implicit memory and familiarity draw on gains in stimulus-related processing fluency for old, compared with novel, stimuli, but recollection does not. Recently, it has been demonstrated that processing fluency itself resides in stimulus-specific motor simulations or reenactment (e.g., covert pronouncing simulations for words as stimuli). Combining these lines of evidence, it was predicted that stimulus-specific motor interference preventing simulations should impair both implicit memory and familiarity but leave recollection unaffected. This was tested for words as verbal stimuli associated to pronouncing simulations in the oral muscle system (but also for tunes as vocal stimuli and their associated vocal system, Experiment 2). It was found that oral (e.g., chewing gum), compared with manual (kneading a ball), motor interference prevented mere exposure effects (Experiments 1-2), substantially reduced repetition priming in word fragment completion (Experiment 3), reduced the familiarity estimates in a remember-know task (Experiment 5) and in receiver-operating characteristics (Experiment 6), and completely neutralized familiarity measured by self-reports (Experiment 4) and skin conductance responses (Experiment 7), while leaving recollection and free recall unaffected (across Experiments 1-7). This pattern establishes a rare memory dissociation in healthy participants, that is, explicit without implicit memory or recognizing without feeling familiar. Implications for embodied memory and neuropsychology are discussed.     

An experimental evaluation of tic suppression and the tic rebound effect

Tourette's syndrome (TS) is a neurobiological disorder consisting of motor and vocal tics that are thought to be temporarily suppressible. Many professionals, however, believe that a paradoxical increase in tic frequency (above baseline levels) occurs when efforts to suppress have ceased (i.e., a rebound effect). To date, little research has investigated tic suppression or its effects. This study examined tic frequency during baseline, suppression, and post-suppression conditions using an experimental preparation reported to reliably produce tic suppression in children. Six children with TS and one with chronic tic disorder (CTD) were recorded during baseline and repeated suppression and post-suppression conditions. Tic frequency was significantly lower during suppression as compared to baseline. Although tic frequency during post-suppression was higher than during suppression, it was lower than baseline levels, arguing against a "rebound" effect of tic suppression. Exploratory analyses revealed that scores on the attention problems subscale of the Child Behavior Checklist significantly predicted tic suppressibility. The relationships between age, tic severity, and tic suppressibility were also explored.     

Do response modality effects support multiprocessor models of divided attention?

Some studies have suggested that dual-task interference is greatly reduced when tasks requiring very different types of responses (e.g., manual and vocal) are combined. However, in those studies, the order of stimuli varied unpredictably. In Experiments 1 and 2, variable stimulus order greatly inflated interference between two manual tasks, whereas interference between a manual and a vocal task was only slightly exacerbated. However, central interference (the psychological refractory period) persisted even with the manual/vocal combination. Selection of 2 manual responses with unknown stimulus order may require a special strategy to preclude intertask intrusion errors. Experiment 3 demonstrated that such errors could be provoked with speed stress. Together, these results reconcile response modality effects with the response selection bottleneck model for dual-task interference (once it is suitably amended).     

Social priming of dyslexia and reduction of the Stroop effect: What component of the Stroop effect is actually reduced?

Recently, Goldfarb, Aisenberg, and Henik (2011) showed that in a manual format of the Stroop task, dyslexia priming eliminates the normal magnitude of the interference-based Stroop-like findings otherwise exhibited by individuals participating in such research. Goldfarb et al. (2011) consequently concluded that the effect of word reading in a Stroop task (i.e., one automatic behavior) can be effectively controlled through an automatic instruction “do not read” (i.e., another automatic behavior). The present study further investigated these ideas by examining when and how dyslexia priming controls different processes involved in a Stroop task. To this end, the original finding was first replicated (Experiment 1) and subsequently extended to the vocal (instead of manual) response modality to examine whether previously reported eliminations of the Stroop effect persist with this response format (i.e., format producing larger Stroop effects). Since past work (e.g., Augustinova & Ferrand, 2012a; Brown, Joneleit et al., 2002; Ferrand & Augustinova, 2013) had suggested that various interventions were likely to reduce (rather than eliminate) the interference-based Stroop-like findings with vocal responses, a further aim of these experiments was to identify the component of these findings that dyslexia priming actually reduces. To this end, the effects of this intervention were examined in a more fine-grained variant of the Stroop task that distinguished between interference resulting from task-irrelevant processes involved in computing the lexical and semantic representations of the word (i.e., a written distractor to ignore) and task-relevant processes involved in the selection of a response (i.e., a color target to name) that are both involved in this task. In line with our past work (e.g., Augustinova & Ferrand, 2012a; Ferrand & Augustinova, 2013), the results of two experiments (Experiments 2 and 3) showed that in the vocal format, dyslexia priming reduces but does not eliminate the normal magnitude of the interference-based Stroop-like findings and that this reduction is solely due to the control of processes involved in the selection of a response (i.e., a color target to name) – processes that are known to be controllable in this format (Ferrand & Augustinova, 2013). Given that in this format, dyslexia priming had no effect on task-irrelevant processes involved in computing the lexical and semantic representations of a written distractor to be ignored – processes that are known to be automatic – further implications for the control of automatic processes via dyslexia priming are considered and an interpretation in terms of a unitary control mechanism for both the manual and vocal formats is proposed.     

Interference effects of stimulus–response modality pairings in dual tasks and their robustness

Recent evidence suggests that the degree of interference in dual-task situations depends crucially on the pairings of input- and output modalities of the two component tasks with increased dual-task costs for modality incompatible (i.e., visual–vocal and auditory–manual) compared to modality compatible (i.e., visual–manual and auditory–vocal) dual tasks. These effects of modality pairings in dual tasks have been related to the overlap of non-preferred processing pathways in modality incompatible tasks. Until now, modality compatibility has not yet been related to other sources of interference in a dual-task context, such as stimulus–response (S–R) compatibility or crosstalk. In the present study, we conducted two experiments using the paradigm of the psychological refractory period (PRP) to test the effects of S–R compatibility and crosstalk on the effects of modality compatibility in temporally overlapping task situations. Experiment 1 revealed an overadditive interaction between stimulus onset asynchrony and modality compatibility for tasks with S–R compatible mappings, indicating that modality compatibility effects are present in different task situations, even when S–R mappings are otherwise compatible. In Experiment 2, we aimed at pinpointing the boundaries of the effects of modality compatibility in dual-task situations. We showed that additional sources of dual-task interference in a modality compatible dual task could overwrite the pronounced PRP effect previously shown for modality incompatible tasks. Taken together, these data provide new evidence that the specific types of stimulus–response modality pairings are an additional factor that might interact with other sources of interference in dual-task situations.     

The effect of acute exercise on cognitive and motor inhibition – Does fitness moderate this effect?

BackgroundGiven the extensive evidence on improvements in cognitive inhibition immediately following exercise, and the literature indicating that cognitive and motor inhibitory functions are mediated by overlapping brain networks, the aim of this study was to assess, for the first time, the effect of moderate intensity acute aerobic exercise on multi-limb motor inhibition, as compared to cognitive inhibition.MethodParticipants were 36 healthy adults aged 40–60 years old (mean age 46.8 ± 5.7), who were randomly assigned to experimental or control groups. One-to-two weeks following baseline assessment, participants were asked to perform a three-limb (3-Limb) inhibition task and a vocal version of the Stroop before and after either acute moderate-intense aerobic exercise (experimental group) or rest (control).ResultsSimilar rates of improvement were observed among both groups from baseline to the pre-test. Conversely, a meaningful, yet non-significant trend was seen among the experimental group in their pretest to posttest improvement in both cognitive and motor tasks. In addition, exploratory analysis revealed significant group differences in favor of the experimental group among highly fit participants on the 3-Limb task. A significant correlation was indicated between the inhibition conditions, i.e., choice in the motor inhibition and color/word (incongruent) in the cognitive inhibition, especially in the improvement observed following the exercise.DiscussionModerate-intensity acute aerobic exercise is a potential stimulator of both multi-limb motor inhibition and cognitive inhibition. It appears that high-fit participants benefit from exercise more than low-fit people. Additionally, performance on behavioral tasks that represent motor and cognitive inhibition is related. This observation suggests that fitness levels and acute exercise contribute to the coupling between cognitive and motor inhibition. Neuroimaging methods would allow examining brain-behavior associations of exercise-induced changes in the brain.     

Response selection and response execution in task switching: evidence from a go-signal paradigm

The present study used a go/no-go signal delay (GSD) to explore the role of response-related processes in task switching. A go/no-go signal was presented at either 100 ms or 1,500 ms after the stimulus. Participants were encouraged to use the GSD for response selection and preparation. The data indicate that the opportunity to select and prepare a response (i.e., long GSD) resulted in a substantial reduction of task-shift costs (Experiment 1) and n-2 task-repetition costs (i.e., backward inhibition; Experiment 2) in the current trial. These results suggest that interference from the preceding trial can be resolved during response selection and preparation. Furthermore, the shift costs and the n-2 repetition costs after no-go trials with long GSD (i.e., response selection but no execution) were markedly smaller than after go trials. These findings suggest that the interference that gives rise to shift costs and n-2 repetition costs is related not solely to response selection but also to response execution. Thus, the present study demonstrates dissociable contributions of response selection and response execution to interference effects in task switching.     

Motivational determinants of motor performance: The hidden second task

Summary The present study was designed to test facilitating and debilitating effects of motivational processes on motor behavior. It was predicted that motivational processes have a more pronounced effect on motor performance when control is frequently transferred to attentional mechanisms (i. e., early in the acquisition phase). The results were consistent with this expectation. A strong motive to achieve success and pretreatment designed to enhance achievement motivation were associated with an increase in the quality of performance. A strong tendency to engage in state-oriented cognitive activities, by contrast, (e.g., thinking about the potential threat to one's selfesteem resulting from failure) was associated with poorer performance, It is concluded that experiments on motor behavior in which subjects are instructed to perform a single motor task may actually involve dual-task (or even multiple-task) performance if some part of the subjects' attentional capacity is used for task-irrelevant cognitive activities.     

Interference and conflict monitoring in individuals with amnestic mild cognitive impairment: A structural study of the anterior cingulate cortex

Amnestic mild cognitive impairment (aMCI) is a clinical condition characterized by memory impairment in the absence of any other cognitive impairment and is commonly associated with high conversion to Alzheimer's disease. Recent evidence shows that executive functions and selective attention mechanisms could also be impaired in aMCI. In this study, we investigated performance differences (i.e., reaction times [RTs] and accuracy) between a group of aMCI participants and a group of age‐matched healthy individuals on the attentional network task (ANT) focusing on situations with increased interference. In particular, we assessed the relationship between interference and conflict effects and grey matter volumes (GMVs) of the anterior cingulate cortex (ACC)/pre‐supplementary motor area in the entire sample because of its crucial role in conflict monitoring. When compared with controls, aMCI participants were less accurate on the ANT, showing increased interference and conflict effects, but no differences in RTs. In addition, aMCI participants exhibited lower GMV in the ACC than controls. While better accuracy for interference and conflict effects was associated with an increase of GMV in the ACC for both groups, RTs from the interference effect were negatively correlated with GMV of the ACC only in aMCI participants. In other words, lower GMV values of the ACC were paralleled with significantly impaired performance in terms of interference resolution. In conclusion, our study suggests the presence of a selective impairment in interference and conflict monitoring in aMCI, which in turn is associated with decreased GMVs in the ACC.     

Pianists exhibit enhanced memory for vocal melodies but not piano melodies

Nonmusicians remember vocal melodies (i.e., sung to la la) better than instrumental melodies. If greater exposure to the voice contributes to those effects, then long-term experience with instrumental timbres should elicit instrument-specific advantages. Here we evaluate this hypothesis by comparing pianists with other musicians and nonmusicians. We also evaluate the possibility that absolute pitch (AP), which involves exceptional memory for isolated pitches, influences melodic memory. Participants heard 24 melodies played in four timbres (voice, piano, banjo, marimba) and were subsequently required to distinguish the melodies heard previously from 24 novel melodies presented in the same timbres. Musicians performed better than nonmusicians, but both groups showed a comparable memory advantage for vocal melodies. Moreover, pianists performed no better on melodies played on piano than on other instruments, and AP musicians performed no differently than non-AP musicians. The findings confirm the robust nature of the voice advantage and rule out explanations based on familiarity, practice, and motor representations.     

Further analysis of modifications to the three-step guided compliance procedure to enhance compliance among children with autism

Three-step guided compliance (vocal prompt, vocal plus model prompt, vocal prompt plus physical guidance) is a commonly used procedure to increase compliance among children with intellectual disabilities. Previous research has suggested that under some conditions, slight modifications to the three-step procedure may enhance its effectiveness. These modifications include omitting the model prompt and decreasing the interprompt interval. In the current study, we evaluated another modification to the procedure: the delivery of a high-preference item contingent upon compliance with the first vocal prompt (i.e., differential reinforcement). For 2 participants with autism, compliance remained low when we implemented differential reinforcement and the guided compliance procedure in isolation. However, compliance improved when we combined differential reinforcement and the three-step guided procedure, suggesting that for at least some children, the combination of contingent access to a high-preference item and the guided compliance procedure is more effective than either intervention alone.     

Socio-cognitive influences on the domain-specificity of prosocial behavior in the second year

The main aim of this study was to explain the domain-specificity of early prosocial behavior in different domains (i.e., helping, comforting, and cooperation) by simultaneously assessing specific socio-cognitive factors (i.e., self-other-differentiation and joint attentional skills) that were hypothesized to be differentially related to the three domains of prosocial behavior. Based on a longitudinal study design, observational and parental report data were collected when toddlers (N = 42) from German urban middle-class families were 15 and 18 months of age. At 15 months, regression analyses indicated differential relationships between socio-cognitive development and prosocial behavior (i.e., joint attentional skills were positively related with helping and, as hypothesized, both joint attentional skills and self-other differentiation were positively related with cooperation). Furthermore, self-other differentiation at 15 months predicted increases in coordination between 15 and 18 months. Finally, between 15 and 18 months, parental reports of socio-cognitive measures increased significantly while behavioral measures of both socio-cognitive concepts and prosocial behavior were stable across time. In sum, these results support the theoretical assumption of domain-specific socio-cognitive influences that constitute differential development of prosocial behavior. Implications of the results for theory and future studies are discussed from different perspectives with a focus on an interference interpretation calling for the integration of socialization approaches to the study of prosocial development.     

Further evaluation of response interruption and redirection as treatment for stereotypy

The effects of 2 forms of response interruption and redirection (RIRD)-motor RIRD and vocal RIRD-were examined with 4 boys with autism to evaluate further the effects of this intervention and its potential underlying mechanisms. In Experiment 1, the effects of motor RIRD and vocal RIRD on vocal stereotypy and appropriate vocalizations were compared for 2 participants. In Experiment 2, the effects of both RIRD procedures on both vocal and motor stereotypy and appropriate vocalizations were compared with 2 additional participants. Results suggested that RIRD was effective regardless of the procedural variation or topography of stereotypy and that vocal RIRD functioned as a punisher. This mechanism was further explored with 1 participant by manipulating the schedule of RIRD in Experiment 3. Results were consistent with the punishment interpretation.     

Motor simulation in verbal knowledge acquisition

Recent research highlights the importance of motor processes for a wide range of cognitive functions such as object perception and language comprehension. It is unclear, however, whether the involvement of the motor system goes beyond the processing of information that is gathered through active action experiences and affects also the representation of knowledge acquired through verbal learning. We tested this prediction by varying the presence of motor interference (i.e., squeezing a ball vs. oddball detection task) while participants verbally acquired functional object knowledge and examined the effects on a subsequent object detection task. Results revealed that learning of functional object knowledge was only impaired when participants performed an effector-specific motor task while training. The present finding of an effector-specific motor interference effect on object learning demonstrates the crucial role of the motor system in the acquisition of novel object knowledge and provides support for an embodied account to perception and cognition.