Two-year-olds learn novel nouns,verbs, and conventional actions from massed or distributed exposures

Two-year-old children were taught either 6 novel nouns, 6 novel verbs, or 6 novel actions over 1 month. In each condition, children were exposed to some items in massed presentations (on a single day) and some in distributed presentations (over the 2 weeks). Children's comprehension and production was tested at 3 intervals after training. In comprehension, children learned all types of items in all training conditions at all retention intervals. For production, the main findings were that (a) production was better for nonverbal actions than for either word type, (b) children produced more new nouns than verbs, (c) production of words was better following distributed than massed exposure, and (d) time to testing (immediate, 1 day, 1 week) did not affect retention. A follow-up study showed that the most important timing variable was the number of different days of exposure, with more days facilitating production. Results are discussed in terms of 2 key issues: (a) the domain-generality versus domain-specificity of processes of word learning and (b) the relative ease with which children learn nouns versus verbs.     

Gender role and personality disorders

Many researchers have hypothesized relationships between personality disorders and gender role (i.e., masculinity and femininity). However, research has not addressed if people who are masculine or feminine more often meet the criteria for personality disorders. The present study examined whether college students (N = 665, 60% women) higher in masculinity or femininity more often exhibited features of the 10 DSM-IV personality disorders. Feminine men exhibited more features of all the personality disorders except antisocial. Dependent traits were associated with higher femininity and lower masculinity. Antisocial traits were associated with masculinity. Both men and women who typically behaved consistent with their gender had more narcissistic and histrionic features, whereas participants who typically behaved unlike their gender had more features of the Cluster A personality disorders.     

Accounting for belief bias in a mental model framework: comment on Klauer, Musch, and Naumer (2000)

K. C. Klauer, J. Musch, and B. Naumer (2000; see record 2000-02818-008) presented a general multinomial model of belief bias effects in syllogistic reasoning. They claimed to map a particular mental model account of belief bias (J. V. Oakhill, P. N. Johnson-Laird, & A. Garnham, 1989; see record 1989-38845-001)) onto this model and to show empirically that it is incorrect. The authors argue that this mental model account does not map onto the multinomial model and that it can account for the data presented by Klauer et al. (Experiments 1-4). The authors further argue that additional data Klauer et al. presented in support of a new model of their own (Experiments 5-8) are explained by this mental model account. The mental model account is, therefore, refuted neither by Klauer et al.'s theoretical analysis nor by any of the results they presented. Furthermore, the account can accommodate more recent findings on belief bias in a more satisfactory way than can alternative models that have been proposed.     

Testing comprehension abilities in users of British Sign Language following CVA

Recent imaging (e.g., MacSweeney et al., 2002) and lesion (Hickok, Love-Geffen, & Klima, 2002) studies suggest that sign language comprehension depends primarily on left hemisphere structures. However, this may not be true of all aspects of comprehension. For example, there is evidence that the processing of topographic space in sign may be vulnerable to right hemisphere damage (e.g., Hickok, Say, Bellugi, & Klima, 1996), and the influence of iconicity on comprehension has yet to be explored. In this study, comprehension testing was conducted with 15 signers with unilateral brain damage, and with elderly Deaf controls. Four tests were administered: a test of iconic and non-iconic noun comprehension, a test of verb and sentence comprehension, a test of locative sentence comprehension, and a test of classifier comprehension. All tests were administered in British Sign Language (BSL), a language that has only recently been explored with lesioned signers (see Atkinson, Marshall, Thacker, & Woll, 2004; Marshall, Atkinson, Thacker, Woll, & Smulevitch, 2004; Marshall, Atkinson, Woll, & Thacker, in press). People with left hemisphere damage were impaired relative to controls on all tests. Those with right hemisphere damage performed well in the first two tests, but were impaired on locative sentences and classifiers. Neither group showed any effect of iconicity. The results shed further light on the laterality of sign language comprehension.     

Cortical regions associated with different aspects of object recognition performance

In the present object recognition study, we examined the relationship between brain activation and four behavioral measures: error rate, reaction time, observer sensitivity, and response bias. Subjects perceptually matched object pairs in which structural similarity (SS), an index of structural differentiation, and exposure duration (DUR), an index of task difficulty, were manipulated. The SS manipulation affected the fMRI signal in the left anterior fusiform and parietal cortices, which in turn reflected a bias to respond same. Conversely, an SS-modulated fMRI signal in the right middle frontal gyrus reflected a bias to respond different. The DUR manipulation affected the fMRI signal in occipital and posterior fusiform regions, which in turn reflected greater sensitivity, longer reaction times, and greater accuracy. These findings demonstrate that the regions most strongly implicated in processing object shape (SS-modulated regions) are associated with response bias, whereas regions that are not directly involved in shape processing are associated with successful recognition performance.