Age trends in stimulus overselectivity

Stimulus overselectivity refers to the phenomenon whereby stimulus control over behavior is exerted only by a limited subset of the total number of stimuli present during discrimination learning. It often is displayed by individuals with autistic spectrum disorders or learning disabilities, but is not exclusive to those groups. The present studies investigated the impact of aging on stimulus control and overselectivity. Three age groups--18-22, 47-55, and 70-80 year olds-were studied in two experiments. All participants were trained on a simple discrimination task, randomly assigned to one of two conditions (either with or without a distractor task), and then tested for the emergence of overselectivity (Experiment 1). In Experiment 2 responding controlled by the overselected stimulus elements was reduced by introducing a verbal punisher. In subsequent tests, control of behavior by the previously underselected elements from Experiment 1 was enhanced across the two younger age groups but not the oldest group of participants. The results are discussed in relation to the attention-deficit and overshadowing accounts of overselectivity.     

A preliminary evaluation of the emergence of novel mand forms

Strategies that produce generalized responding are valuable, especially with regard to language acquisition, because relatively little training may result in large behavior changes. Conditions that result in generalized manding were analyzed in the current study. We demonstrated in reversal designs that undesirable or single-word responses were the predominant mand forms of 3 preschool children. Multiple baseline designs with 2 participants and a reversal design with 1 participant were then used to demonstrate the extent to which differential reinforcement of single-word mands (e.g., "cars") or framed mands (e.g., "I want the cars, please") would result in the emergence of other single-word and framed mands for different items (e.g., mands for music, puppets, or puzzles). Results showed that prompting and differential reinforcement of one or two mand frames resulted in the emergence of other framed mands for all participants.     

Further evaluation of emerging speech in children with developmental disabilities: training verbal behavior

The conceptual basis for many effective language-training programs are based on Skinner's (1957) analysis of verbal behavior. Skinner described several elementary verbal operants including mands, tacts, intraverbals, and echoics. According to Skinner, responses that are the same topography may actually be functionally independent. Previous research has supported Skinner's assertion of functional independence (e.g., Hall & Sundberg, 1987; Lamarre & Holland, 1985), and some research has suggested that specific programming must be incorporated to achieve generalization across verbal operants (e.g., Sigafoos, Reichle, & Doss, 1990). The present study provides further analysis of the independence of verbal operants when teaching language to children with autism and other developmental disabilities. In the current study, 3 participants' vocal responses were first assessed as mands or tacts. Generalization for each verbal operant across alternate conditions was then assessed and subsequent training provided as needed. Results indicated that generalization across verbal operants occurred across some, but not all, vocal responses. These results are discussed relative to the functional independence of verbal operants as described by Skinner.     

Assessment of the functions of vocal behavior in children with developmental disabilities: a replication

Although experimental analysis methodologies have been useful for identifying the function of a wide variety of target behaviors (e.g., Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994), only recently have such procedures been applied to verbal operants (Lerman et al., 2005). In the current study, we conducted a systematic replication of the methodology developed by Lerman et al. Participants were 4 children who had been diagnosed with developmental disabilities and who engaged in limited vocal behavior. The function of vocal behavior was assessed by exposing target vocal responses to experimental analyses. Results showed that experimental analyses were generally useful for identifying the functions of vocal behavior across all participants.     

A day of great illumination: B. F. Skinner's discovery of shaping

Despite the seminal studies of response differentiation by the method of successive approximation detailed in chapter 8 of The Behavior of Organisms (1938), B. F. Skinner never actually shaped an operant response by hand until a memorable incident of startling serendipity on the top floor of a flour mill in Minneapolis in 1943. That occasion appears to have been a genuine eureka experience for Skinner, causing him to appreciate as never before the significance of reinforcement mediated by biological connections with the animate social environment, as opposed to purely mechanical connections with the inanimate physical environment. This insight stimulated him to coin a new term (shaping), and also led directly to a shift in his perspective on verbal behavior from an emphasis on antecedents and molecular topographical details to an emphasis on consequences and more molar, functional properties in which the social dyad inherent to the shaping process became the definitive property of verbal behavior. Moreover, the insight seems to have emboldened Skinner to explore the greater implications of his behaviorism for human behavior writ large, an enterprise that characterized the bulk of his post-World War II scholarship.     

Relations between enabling skills and reading comprehension: a follow-up study of Latvian students from first to second grade

In order to examine the relationships among various phonological skills and reading comprehension, Latvian children were followed from grade 1 to grade 2 and were tested with a battery of phonological, word reading, and reading comprehension tasks. A principal component analysis of the phonological tasks revealed three salient factors: a phonemic awareness factor, a rapid naming factor, and a short-term memory factor. In order to analyze the relationship between various phonological skills and reading comprehension, a structural modeling analysis was performed. Phonemic awareness and rapid naming explained approximately the same amount of unique variance in reading comprehension, but phonemic awareness had most predictive power indirectly via word decoding. Only rapid naming had a significant direct impact on reading comprehension.     

A comparison of metacognitions in patients with hallucinations,delusions, panic disorder,and non-patient controls

This study tested the hypothesis that metacognitions are a general vulnerability factor for psychological disorder. It was predicted that patients with psychosis (hallucinations or delusions), and patients with panic disorder would score higher than non-patients on measures of metacognition. Moreover, it was hypothesised that patients showing most dysregulation of thinking (voice-hearers) would endorse significantly higher metacognition scores than individuals in the other groups. The Meta-Cognitions Questionnaire (MCQ: ) was administered to patients who met DSM-IV criteria for schizophrenia spectrum disorders with auditory hallucinations, patients who met DSM-IV criteria for schizophrenia spectrum disorders with persecutory delusions, patients who met DSM-IV criteria for panic disorder and non-patients. The results showed that psychotic patients who experience auditory hallucinations tended to exhibit higher levels of dysfunctional metacognitive beliefs than other patient groups, scoring significantly higher than at least two of the three control groups on positive beliefs about worry, negative beliefs about uncontrollability and danger, cognitive confidence and negative beliefs including superstition, punishment and responsibility. It was also found that the metacognitive beliefs of patients with persecutory delusions and panic patients were often similar to each other, and elevated in comparison to non-patients, suggesting that such beliefs are generic vulnerability factors. The theoretical and clinical implications of these findings are discussed.     

ERP correlates of auditory negative priming

Negative priming refers to slowed down reactions when the distractor on one trial becomes the target on the next. Following two popular accounts, the effect might be due either to inhibitory processes associated with the frontal cortex, or to an ambiguity in the retrieval of episodic information. We used event-related brain potentials (ERPs) to identify the processing stage primarily associated with negative priming. In an auditory categorization task, reactions in negative priming trials were compared to reactions in a standard control (unrelated primes and probes) and a repetition control (attended prime=ignored probe) condition. Reactions were slower for negative priming than for standard control (Delta32 ms) and repetition control trials (Delta64 ms). The corresponding ERP effect was reflected in an attenuation of a sustained parietal positivity extending from 300 to 600 ms. Because corresponding ERP components were found to be sensitive to stimulus recognition and familiarity, the results may be interpreted to support an episodic retrieval account of negative priming.     

Inconsistency as an interactional problem: a lesson from political rhetoric

The classical theory of cognitive dissonance suggests that when two related cognitions are mutually inconsistent, one of them will change to restore consistency. However, Billig suggests that inconsistency is primarily an interactional problem between subjects and not a cognitive problem within a subject. In the current paper, we adopt Billig's rhetorical approach to inconsistency and study inconsistency as an interactional problem in the context of political rhetoric. More specifically, we use Action-Implicative Discourse Analysis to identify the discursive strategies the former Israeli Prime Minister Benjamin Netanyahu, used to cope with the inconsistency between his national ideology and his contradictory behavior during his short term in office.     

Memory for melody: infants use a relative pitch code

Pitch perception is fundamental to melody in music and prosody in speech. Unlike many animals, the vast majority of human adults store melodic information primarily in terms of relative not absolute pitch, and readily recognize a melody whether rendered in a high or a low pitch range. We show that at 6 months infants are also primarily relative pitch processors. Infants familiarized with a melody for 7 days preferred, on the eighth day, to listen to a novel melody in comparison to the familiarized one, regardless of whether the melodies at test were presented at the same pitch as during familiarization or transposed up or down by a perfect fifth (7/12th of an octave) or a tritone (1/2 octave). On the other hand, infants showed no preference for a transposed over original-pitch version of the familiarized melody, indicating that either they did not remember the absolute pitch, or it was not as salient to them as the relative pitch.