Conditional Heresies

The principles of Conditional Excluded Middle (CEM ) and Simplification of Disjunctive Antecedents (SDA) have received substantial attention in isolation. Both principles are plausible generalizations about natural language conditionals. There is however little discussion of their interaction. This paper aims to remedy this gap and explore the significance of having both principles constrain the logic of the conditional. Our negative finding is that, together with elementary logical assumptions, CEM and SDA yield a variety of implausible consequences. Despite these incompatibility results, we open up a narrow space to satisfy both. We show that, by simultaneously appealing to the alternative-introducing analysis of disjunction and to the theory of homogeneity presuppositions, we can satisfy both. Furthermore, the theory that validates both principles resembles a recent semantics that is defended by Santorio on independent grounds. The cost of this approach is that it must give up the transitivity of entailment: we suggest that this is a feature, not a bug, and connect it with recent developments of intransitive notions of entailment.     

Effects of Expectancies and Personalized Feedback on Fat Consumption, Taste, and Preference

Previous studies have shown that people develop expectations about the taste and effects of consumed substances and that those expectations can guide future behavior, cognitions, and affect. Identifying expectancies for the taste of both low- and high-fat foods is important in determining people's reactions to changes in their diets. Study 1 was designed to determine the existence of expectancies for the taste of low-and high-fat foods and the effects of these expectations on food consumption and preference. Ninety-seven subjects tasted a bowl of ice cream and rated the taste on taste judgment forms. The fat content of the ice cream (high- versus low-fat) and the expectancy of high- versus low-fat content were independently manipulated using a balanced placebo design. Expectancy affected the consumption of ice cream under most circumstances: For women who received high-fat ice cream and for men, regardless of the ice cream received, consumption was higher when high-fat ice cream was expected than when low-fat ice cream was expected. Study 2 was designed to investigate the effects of educating individuals about the diet-cancer link on consumption and preference. Receiving information about diet and cancer, especially when the information was personalized, decreased overall consumption and reported preference. Current levels of daily fat consumption also affected laboratory consumption and preference. This study has several implications for interventions to lower dietary fat.     

Visual search for simple volumetric shapes

Five experiments measured reaction time (RT) to detect the presence or absence of a simple volumetric shape (target) dependent on the number of display items (distractors) and their depicted three-dimensional (3-D) orientation. Experiments 1–4 examined every pairwise combination of two different simple volumetric shapes in two 3-D orientations. Conditions exhibiting “pop-out” could be predicted by differences in their two-dimensional (2-D) features. Conditions in which search was slower support previously found search asymmetries for particular 2-D features. When the distractors were a mixture of the other shapes in the same 3-D orientation, search was serial, except when the target had a curved principal axis (Experiment 5). The results suggest that these simple volumetric shapes are not processed preattentively.     

Psychiatric sequelae of low birth weight at 6 years of age

The study examined the association between low birth weight (LBW) (2,500 g) and attention deficit hyperactivity disorder (ADHD) in two socioeconomically disparate populations. LBW and normal birth weight (NBW) children from the 1983 to 1985 newborn lists of an urban and a suburban hospital in Southeast Michigan were randomly selected. A total of 823 children, 473 LBW and 350 NBW, participated. Data were gathered in 1990 to 1992, when the children were 6 to 7 years of age. The National Institute of Mental Health Diagnostic Interview Schedule for children—Parent version (DISC-P) was used to elicit information on DSM-III-R diagnoses of simple phobia, overanxious, separation anxiety, oppositional defiant, and ADHD. Teachers' ratings of behavior problems were obtained. LBW was associated with ADHD but not with childhood anxiety disorders or oppositional defiant disorder. The association was stronger in the urban than in the suburban population. Data from teachers' ratings revealed an association between LBW and attention problems. The prognostic significance of the observed psychopathology at 6 years of age requires follow-up assessment as the children mature.This research was supported by NIMH research grant MH-44586 and NIMH Research Scientist Development Award MH-00380 to Dr. Breslau.     

Can Communication Deviance Be Measured in a Family Problem-Solving Interaction?

Communication deviance (CD) refers to confusing and fragmented communication that prevents family members from attaining a shared focus of attention and meaning. Levels of communication deviance based on individual parental projective test protocols--Thematic Apperception Test (TAT) and Rorschach--have repeatedly been found to be higher in parents of schizophrenic offspring than in parents of normal or nonpsychotic offspring. CD has also been measured in family transactions in which parents and their offspring interact with one another around a projective test stimulus, the Consensus Rorschach. There have been relatively few attempts to measure specific CD codes in familial interaction that is not initiated around an ambiguous visual stimulus. The present article examines the reliability and construct validity of an interactional measure (ICD) obtained from family transactions in which parents and patients are working toward the solution of a salient family problem. ICD from this family problem-solving task was compared to more traditional measures of CD from parental TAT protocols in a sample of 59 parents of 37 recent-onset schizophrenic patients. Results indicated that CD could be reliably measured in an interactive setting not initiated around a projective test stimulus, and provided evidence for the construct validity of ICD.