Homonymy in the Lexicons of Young Children Acquiring American Sign Language

The incidence of homonymy in children's early sign language production was examined in nine young children of deaf parents. Analysis of parental reports of how their children formed their signs revealed that all of the children produced homonymous forms (i.e., a single manual form used to represent two or more different adult target signs). Altogether, the children were reported as producing 26 sets of homonymous forms to represent 59 adult target signs. This incidence of homonymy in the children's early signing did not differ significantly from the incidence of homonymy previously reported in a study of normally developing children acquiring spoken language. This finding is interpreted as indicating an important similarity in language acquisition processes across language modalities. Analysis of the sign formational characteristics of the children's homonymous forms revealed that the children's signs and the adult target signs typically shared a common location aspect. The movement and handshape aspects of the adult target signs were less frequently retained in the children's homonymous forms.     

Genetic and Environmental Influences on the Continuous Scales of the Myers-Briggs Type Indicator: An Analysis Based on Twins Reared Apart

The Myers-Briggs Type Indicator was administered to a sample of 61 monozygotic twins reared apart (MZA), 49 dizygotic twins reared apart (DZA), and 92 spouses, who participated in the Minnesota Study of Twins Reared Apart (MISTRA) from 1979 to 1995. Twins' scores on the continuous scales were subjected to behavior genetic model-fitting procedures. Extraversion-Introversion and Thinking-Feeling yielded heritabilities of about .60, consisting largely of nonadditive genetic variance. Sensing-Intuition and Judgment-Perception yielded heritabilities of about .40, consisting largely of additive genetic variance. Spouse correlations for three of the four scales were near zero and not statistically significant; one spouse correlation (Sensing-Intuition) was modestly positive and statistically significant.     

Potential perceptual bases for successful use of a vibrotactile speech perception aid

This paper examines the possibility that perception of vibrotactile speech stimuli is enhanced in adults with early and life-long use of hearing aids. We present evidence that vibrotactile aid benefit in adults is directly related to the age at which the hearing aid was fitted and the duration of its use. The stimulus mechanism responsible for this effect is hypothesized to be long-term vibrotactile stimulation by high powered hearing aids. We speculate on possible mechanisms for enhanced vibrotactile speech perception as the result of hearing aid use: (1) long-term experience receiving degraded or impoverished speech stimuli results in a speech processing system that is more effective for novel stimuli, independent of perceptual modality; and/or (2) long-term sensory/perceptual experience causes neural changes that result in more effective delivery of speech information via somatosensory pathways.     

Perceptions of Liver Transplant Candidates with or Without an Alcohol Use History

Cirrhosis secondary to alcohol use is a primary cause of liver disease and a medical condition for which liver transplantation is a viable treatment option. However, there remains considerable debate within both the lay and the medical communities regarding the distribution of a scarce medical resource to adults with alcoholism. This study examined college students' perceptions toward an adult, presented in a written vignette, for whom liver transplantation was medically indicated. The influence of gender (female and male) and alcohol use history (no alcohol history, alcoholism history with long-term abstinence, alcoholism history with current use) on these ratings was examined. Subjects rated the adult presented with no alcohol history more positively than they did the adults presented with a history of alcoholism. Also, the adult with no alcohol history was more likely to be offered transplantation and was given higher priority ratings for transplantation by subjects. While subjects' own alcohol use history and organ donor registration status were not associated with ratings, having a family member with an alcohol problem and personally knowing a transplant recipient were related to more favorable ratings toward the adult presented in the vignette. Implications of these findings as well as limitations of the study are discussed.     

Kripke on functionalism and automata

Saul Kripke has proposed an argument to show that there is a serious problem with many computational accounts of physical systems and with functionalist theories in the philosophy of mind. The problem with computational accounts is roughly that they provide no noncircular way to maintain that any particular function with an infinite domain is realized by any physical system, and functionalism has the similar problem because of the character of the functional systems that are supposed to be realized by organisms. This paper shows that the standard account of what it is for a physical system to compute a function can avoid Kripke's criticisms without being reduced to circularity; a very minor and natural elaboration of the standard account suffices to save both functionalist theories and computational accounts generally.I am indebted to Saul Kripke for several helpful discussions of this material. I also benefitted from the discussions following the presentations of earlier versions of this paper at the University of Pennsylvania (February, 1984), UCLA (June, 1984), and Rutgers University (December, 1984), and particularly from my discussions with Elizabeth Spelke and Scott Weinstein.