Sentence processing deficits in two Cantonese aphasic patients

This paper reports the performances of two Cantonese aphasics on tasks examining their sentence processing deficits. The data on sentence comprehension show that thematically noncanonical sentences, full passives, and subject-gap sentences present greater difficulty to these patients than canonical sentences, truncated passives, and object-gap sentences, respectively. These patterns are consistent with previous observations on Chinese aphasics and are expected given the structural differences between Chinese and English. In a Cantonese grammaticality judgment test, a set of structures are identified that can elicit clear judgments from normal subjects and aphasics, contrary to the claim that grammaticality judgments in Chinese are probabilistic and fragile. Most interestingly, the patients' overall performance patterns reveal a double dissociation between sentence comprehension and judgment of sentence well-formedness, suggesting that the two tasks are supported by independent processing mechanisms.     

A psychometric evaluation of the social skills rating system in children with attention deficit hyperactivity disorder

The social skills rating system (SSRS) was developed to assess social skills of children, as observed by multiple raters (teacher, parent, child). Studies of the SSRS have been conducted with handicapped, mentally retarded and learning disabled children. No studies have reported the psychometric properties of the SSRS in a clinical ADHD sample. This is important, because deficient social functioning is associated with ADHD. The present study assesses the psychometric properties of the teacher, parent and child versions of the SSRS in children with ADHD (n = 123), and normal controls (n = 239). Also, the social skills of children with ADHD, as rated on the SSRS were examined. Results support the factor structure and internal consistency of the original SSRS-teacher version. Moreover, support was found for 3 out of 4 scales of the SSRS-parent version. The factor structure of the SSRS-child version could not be replicated. An explanatory factor analysis on the SSRS-child version yielded two factors. Evidence was found for discriminative ability of the SSRS between normal controls and children with ADHD. Finally, informant agreement between raters was found to be poor.     

Ruminative coping and post-event processing in social anxiety

Cognitive models of social anxiety implicate various factors in the initiation and maintenance of socially anxious states, including anticipatory processing, self-focused attention and post-event processing. The present study focused on post-event processing, which is a post-mortem analysis following a social event that is described as ruminative in nature and serves to maintain social anxiety. Participants (N=112; 64 women, 48 men) were presented with vignettes that involved making mistakes in public and were instructed to record their thoughts to allow for the examination of the content of post-event processing. Ruminative coping and distraction were assessed via self-report. Results indicated that participants high in social anxiety (n=55) were more likely to ruminate and less likely to distract when faced with socially anxious stressors compared to those low in social anxiety (n=57). Further, as hypothesized, participants high in social anxiety recorded more negative thoughts and more upward counterfactual thoughts ('if only' type thoughts on how things could have been better; associated with negative affect) compared to those low in social anxiety. These results are discussed in terms of cognitive models of social anxiety.     

Psychiatric correlates of childhood shyness in a nationally representative sample

Relations between adult anxiety and mood disorders and retrospective reports of excessive childhood shyness were investigated in the US National Comorbidity, Survey (n=5877). Results indicated that 26% of women and 19% of men described themselves as 'very shy' when they were growing up. Of these shy individuals, 53% of women and 40% of men met criteria for a lifetime diagnosis of one or more anxiety or mood disorders. Relations between excessive shyness and each of the anxiety and mood disorders were examined after adjusting for elevated neuroticism, self-criticism, and low maternal care. The largest odds ratios were found for social phobia in both men and women, particularly for the complex subtype of this disorder. Significant associations also emerged for posttraumatic stress disorder in women and for major depressive disorder in men. Childhood shyness remained significantly associated with a lifetime history of social phobia when individuals with current (past year) social phobia were excluded from the analysis. The results of this study suggest that childhood shyness is strongly related to the complex subtype of social phobia in the general population. Excessive shyness does not appear to be strongly associated with other anxiety and mood disorders when related psychosocial and developmental dimensions are statistically controlled. Finally, many individuals who report excessive childhood shyness do not meet criteria for any anxiety or mood disorder. In a similar fashion, approximately 50% of individuals with a lifetime history of complex social phobia did not view themselves as very shy when growing up.     

Quantity judgments and individuation: evidence that mass nouns count

Three experiments explored the semantics of the mass-count distinction in young children and adults. In Experiments 1 and 2, the quantity judgments of participants provided evidence that some mass nouns refer to individuals, as such. Participants judged one large portion of stuff to be "more" than three tiny portions for substance-mass nouns (e.g. mustard, ketchup), but chose according to number for count nouns (e.g. shoes, candles) and object-mass nouns (e.g. furniture, jewelry). These results suggest that some mass nouns quantify over individuals, and that therefore reference to individuals does not distinguish count nouns from mass nouns. Thus, Experiments 1 and 2 failed to support the hypothesis that there exist one-to-one mappings between mass-count syntax and semantics for either adults or young children. In Experiment 3, it was found that for mass-count flexible terms (e.g. string, stone) participants based quantity judgments on number when the terms were used with count syntax, but on total amount of stuff when used with mass syntax. Apparently, the presence of discrete physical objects in a scene (e.g. stones) is not sufficient to permit quantity judgments based on number. It is proposed that object-mass nouns (e.g. furniture) can be used to refer to individuals due to lexically specified grammatical features that normally occur in count syntax. Also, we suggest that children learning language parse words that refer to individuals as count nouns unless given morpho-syntactic and referential evidence to the contrary, in which case object-mass nouns are acquired.     

The social context of imitation in infancy

Infants increasingly generalize deferred imitation across environmental contexts between 6 and 18 months of age. In three experiments with 126 6-, 9-, 12-, 15-, and 18-month-olds, we examined the role of the social context in deferred imitation. One experimenter demonstrated target actions on a hand puppet, and a second experimenter tested imitation 24h later. When the second experimenter was novel, infants did not exhibit deferred imitation at any age; when infants were preexposed to the second experimenter, all of them did. Imitating immediately after the demonstration also facilitated deferred imitation in a novel social context at all ages but 6 months. Infants' pervasive failure to exhibit deferred imitation in a novel social context may reflect evolutionary selection pressures that favored conservative behavior in social animals.     

An experimental study of the emergence of human communication systems

The emergence of human communication systems is typically investigated via 2 approaches with complementary strengths and weaknesses: naturalistic studies and computer simulations. This study was conducted with a method that combines these approaches. Pairs of participants played video games requiring communication. Members of a pair were physically separated but exchanged graphic signals through a medium that prevented the use of standard symbols (e.g., letters). Communication systems emerged and developed rapidly during the games, integrating the use of explicit signs with information implicitly available to players and silent behavior-coordinating procedures. The systems that emerged suggest 3 conclusions: (a) signs originate from different mappings; (b) sign systems develop parsimoniously; (c) sign forms are perceptually distinct, easy to produce, and tolerant to variations.     

Bottlenose dolphin (Tursiops truncatus) calves appear to model their signature whistles on the signature whistles of community members

Bottlenose dolphins are unusual among non-human mammals in their ability to learn new sounds. This study investigates the importance of vocal learning in the development of dolphin signature whistles and the influence of social interactions on that process. We used focal animal behavioral follows to observe six calves in Sarasota Bay, Fla., recording their social associations during their first summer, and their signature whistles during their second. The signature whistles of five calves were determined. Using dynamic time warping (DTW) of frequency contours, the calves signature whistles were compared to the signature whistles of several sets of dolphins: their own associates, the other calves associates, Tampa Bay dolphins, and captive dolphins. Whistles were considered similar if their DTW similarity score was greater than those of 95% of the whistle comparisons. Association was defined primarily in terms of time within 50 m of the mother/calf pair. On average, there were six dolphins with signature whistles similar to the signature whistles of each of the calves. These were significantly more likely to be Sarasota Bay resident dolphins than non-Sarasota dolphins, and (though not significantly) more likely to be dolphins that were within 50 m of the mother and calf less than 5% of the time. These results suggest that calves may model their signature whistles on the signature whistles of members of their community, possibly community members with whom they associate only rarely.     

Tool-use learning in Tonkean macaques (Macaca tonkeana)

The transmission of tool use is a rare event in monkeys. Such an event arose in a group of semi-free-ranging Tonkean macaques (Macaca tonkeana) in which leaning a pole against the parks fence (branch leaning) appeared and spread to several males. This prompted us to test individual and social learning of this behavior in seven young males. In the first experiment, three males learned individually to obtain a food reward using a wooden pole as a climbing tool. They began using the pole to retrieve the reward only when they could alternatively experience acting on the object and reaching the target. In a second experiment, we first tested whether four other subjects could learn branch leaning after having observed a group-mate performing the task. Despite repeated opportunities to observe the demonstrator, they did not learn to use the pole as a tool. Hence we exposed the latter subjects to individual learning trials and they succeeded in the task. Tool use was not transmitted in the experimental situation, which contrasts with observations in the park. We can conclude that the subjects were not able to recognize the target as such. It is possible that they recognized it and learned the task individually when we alternated the opportunity to act upon the object and to reach the reward. This suggests that these macaques could then have associated the action they exercised upon the pole and the use of the pole as a means to reach the reward.     

Something from nothing: exploring dimensions of children's knowing through the repeated reading of favourite books

Witte‐Townsend and DiGiulio explore some of the dimensions of knowing that children, teachers and parents may engage together during story‐time. They reflect on some of their own long‐term relationships with children and children's books, especially Phoebe Gilman's Gilman P 1992 Something from nothing (New York, NY, Scholastic Inc)  [Google Scholar] Something from nothing (published in 1992) and Simms Taback's Taback S 1999 Joseph had a little overcoat (New York, NY, Viking‐Penguin)  [Google Scholar] Joseph had a little overcoat, published in 1999. The authors probe issues such as why children ask to hear a favourite story over and over and why they suddenly abandon all interest and move on to a new book. They explore the meaning of the silences that sometimes arise during story‐time, pooling around the young listeners as the last words of the book are read. Witte‐Townsend and DiGiulio remind us of the value of literature in the lives of children and they affirm that the reading and re‐reading of favourite stories enables the understanding of complex human issues and contributes significantly to social, emotional and spiritual growth.