Mechanisms Underlying the Emergence of Object Representations during Infancy

The effects of individual versus category training, using behavioral indices of stimulus discrimination and neural ERPs indices of holistic processing, were examined in infants. Following pretraining assessments at 6 months, infants were sent home with training books of objects for 3 months. One group of infants was trained with six different strollers labeled individually, and another group was trained with the same six strollers labeled at the category level (i.e., “stroller”). Infants returned for posttraining assessments at 9 months. Discrimination of objects was facilitated for infants trained with the individually labeled strollers but was unchanged after training at the category level. Relative to pretraining and to category-level training, individual-level training resulted in increased holistic processing of strollers recorded over occipital brain regions. These results suggest that labeling nonface objects individually, in infancy, facilitates discrimination and leads to the emergence of holistic neural representations not present with category-level labeling.

Effects of peer group rejection, group membership, and group norms, on children's outgroup prejudice

This study examined the effects on 6- and 8-year old children ( n = 160) of rejection versus acceptance by an initial group, the reason for the rejection or acceptance (personal versus category-based), and the norms (inclusion versus exclusion) of a new group to which the children were assigned, on their negative affect and attitudes towards the initial group, new group and an outgroup. Results showed that rejected compared with accepted children had a negative attitude towards the initial group, but that both were equally positive towards their new group. In addition, whereas accepted participants were less positive towards the outgroup, rejected participants displayed outgroup prejudice. Results also revealed main effects on group attitudes of participants' age and group norms, as well as a peer status × status reason interaction, but participants' negative affect was only affected by their age. The basis of the effect of peer group rejection on outgroup prejudice is discussed.

Delusions: The Continuum Versus Category Debate

Objective: In this paper I critically review the recently developed idea that delusions are best considered as part of a continuum along with more ordinary human beliefs. Method: A literature review of the area was guided by a Medline search, and supplemented with material already known to the author. Claims that recent research supports the continuum hypothesis is critiqued. Results: The argument and evidence advanced for the continuum approach to delusions depends largely on: (i) inadequacies of prevailing definitions of delusion, particularly in the light of evidence that delusional conviction is often not absolute; and (ii) the high prevalence of unusual beliefs in community populations. To the extent that the delusion construct contains much in addition to conviction and unusual or false belief content, the continuity approach is weak. The category of delusions continues to have some validity. Conclusion: Both categorical and continuous approaches to delusions have validity that depends at any time on our immediate clinical or scientific needs. No definitive resolution of the category versus continuum debate is likely to emerge.