Processing variant forms in spoken word recognition: the role of variant frequency

Recognition of a spoken word phonological variant--schwa vowel deletion (e.g., corporate --> corp'rate)--was investigated in vowel detection (absent/present) and syllable number judgment (two or three syllables) tasks. Variant frequency corpus analyses (Patterson, LoCasto, & Connine, 2003) were used to select words with either high or low schwa vowel deletion rates. Speech continua were created for each word in which schwa vowel length was manipulated (unambiguous schwa-present and schwa-absent endpoints, along with intermediate ambiguous tokens). Matched control nonwords were created with identical schwa vowel continua and surrounding segments. The low-deletion-rate words showed more three-syllable judgments than did the high-deletion-rate words. Matched control nonwords did not differ as a function of deletion rate. Experiments 2 and 3 showed a lexical decision reaction time advantage for more frequent surface forms, as compared with infrequent ones, for schwa-deleted (Experiment 2) and schwa-present (Experiment 3) stimuli. The results are discussed in terms of representations of variant forms of words based on variant frequency.     

SD-squared: on the association between semantic dementia and surface dyslexia

Within the connectionist triangle model of reading aloud, interaction between semantic and phonological representations occurs for all words but is particularly important for correct pronunciation of lower frequency exception words. This framework therefore predicts that (a) semantic dementia, which compromises semantic knowledge, should be accompanied by surface dyslexia, a frequency-modulated deficit in exception word reading, and (b) there should be a significant relationship between the severity of semantic degradation and the severity of surface dyslexia. The authors evaluated these claims with reference to 100 observations of reading data from 51 cases of semantic dementia. Surface dyslexia was rampant, and a simple composite semantic measure accounted for half of the variance in low-frequency exception word reading. Although in 3 cases initial testing revealed a moderate semantic impairment but normal exception word reading, all of these became surface dyslexic as their semantic knowledge deteriorated further. The connectionist account attributes such cases to premorbid individual variation in semantic reliance for accurate exception word reading. These results provide a striking demonstration of the association between semantic dementia and surface dyslexia, a phenomenon that the authors have dubbed SD-squared.     

The development of antisocial behaviour patterns in childhood and adolescence

A developmental model of antisocial behaviour is presented in this paper. Arguments and evidence are presented for the position that although many factors such as parent criminality, social and economic disadvantage, child temperament, and marital discord systematically affect the development of antisocial child behaviour, their influence is mediated by the extent to which they disrupt day-to-day parenting practices. Particularly, it is argued that irritable, ineffective discipline and poor parental monitoring are the most proximal determinants of the early development and maintenance of antisocial behaviour. The implications of this model for prevention and intervention in child conduct problems are discussed, using examples of promising clinical work that focuses on direct parent training.     

The Gradual Deterioration of Syntax and Semantics in a Patient with Progressive Aphasia

FM is a progressive aphasic patient whose language comprehension we studied over a 4-year period. We developed a variety of implicit and explicit tasks to chart progressive changes in the representation of linguistic knowledge (in particular, syntax and semantics) and the automatic and controlled processes which operate on that knowledge. The representation of FM's semantic knowledge remained essentially intact over the years, but she became increasingly impaired at combining the meanings of words. She also showed progressive impairments in the processes of syntactic combination. Thus, FM's disease resulted in a progressive inability to engage in those combinatorial processes necessary for the normal comprehension of a spoken utterance. This is not a selective deficit in the traditional sense of the term, since aspects of both syntax and semantics are implicated; but it is selective in the sense that other aspects of language comprehension remain intact.     

Cholinergic receptor antagonists impair formation of intermediate-term memory in the chick

Several experiments examined the effects of cholinergic receptor antagonists on formation of memory in the chick. Scopolamine produced amnesia in chicks trained on a one-trial peck avoidance task in a dose-dependent manner. Pretraining injection of scopolamine produced amnesia that developed between 15 and 30 min after training, suggesting that scopolamine interferes with intermediate-term memory (ITM), previously described to be active during this time (Patterson, Alvarado, Warner, Bennett, & Rosenzweig, 1986). Pretraining injection of scopolamine or ouabain, an inhibitor of ATPase activity shown previously to inhibit formation of ITM, produced identical time courses of amnesia development, supporting the hypothesis that scopolamine interferes with ITM. Pirenzepine, an inhibitor of M1 muscarinic receptors, was effective in producing amnesia, whereas gallamine, an M2 receptor inhibitor, did not produce amnesia. These results suggest that M1, but not M2, receptors are involved in memory formation in the chick.     

Phonological spelling

A case study is presented of phonological spelling, an acquired spelling disorder in which the primary symptom is the occurrence of phonologically plausible errors (e.g. "flood" → flud). Not all of the patient's spelling errors are as phonologically "perfect" as this example; but it is arguable that the errors primarily derive from a routine which segments a phonological code and assigns orthographic representations to these individual segments. This account of errors in phonological spelling is contrasted with an interpretation of oral reading errors in surface dyslexia. We conclude that errors in the two disorders do not reveal a precise parallel, and that the contrast is partly attributable to the differential role of comprehension in reading and spelling.     

Behavior modification consultation in a Mexican-American school

Following consultation by two psychologists with an elementary school populated primarily by Mexican-American students, absenteeism was chosen as the first problem area to attempt to change. A between-groups experimental design was used to evaluate the effect of contigent rewards on the students' attendance. Analysis of the data showed no improvement in attendance. The results of the study were discussed in terms of (1) a more thorough behavior analysis of the absenteeism problem, (2) methodological restraints of a between-groups experimental design, (3) the need for consultants to be familiar with the community in which they work, and (4) relatedly, the success of the local school psychologist in implementing behavior modification programs.     

Conditioning and post-hospital generalization of nondelusional responses in a chronic psychotic patient

An operant conditioning approach was successful in getting a chronic psychotic patient to give factual answers to direct questions that had previously elicited only delusional responses. Multiple baseline and reversal controls established that the changes were due to the experimental procedure. The subject was a female patient classified as paranoid schizophrenic who had persisted in giving bizarre responses to direct questions regarding her identity, age, and personal history during 26 yr of hospitalization. She was discharged after factual answers to these questions had been obtained, but operant conditioning trials were continued in the community to promote generalization. Two follow-up interviews were conducted 36 and 52 days after discharge to evaluate generalization. No generalization was found in the first interview, but the second gave evidence of some generalization.