Search PubMed⌕ Search

Biomedical subjects

M Siegal

Publications and source records attributed to M Siegal.

At least 19 recordsLinked to original sources
PubMed1998

Preschoolers' understanding of lies and innocent and negligent mistakes.

It has often been proposed that young children are not capable of distinguishing mistakes from lies and that they do not discriminate between the reactions that are generated by innocent and negligent mistakes. In our investigation, children aged 3 to 5 years were asked to choose whether a perpetrator had made a mistake or had lied about a food's contact with contaminants and were required to indicate whether this choice would produce a neutral or a negative reaction in the facial expression of a bystander. In this context, many children distinguished mistakes from lies and displayed an incipient ability to discriminate between lies and negligent mistakes that often generate negative reactions and innocent mistakes that do not.

Child Development↗
PubMed1997

Explicitly questioning the nature of suggestibility in preschoolers' memory and retention.

In research designed to investigate children's suggestible responses on memory tests, 190 preschoolers were read a short story. The same day or six days later, they were exposed to information that was either consistent with the original story details or inconsistent and misleading. One and seven weeks after hearing the story, the children were tested on two types of recognition tasks that involved a choice either between the original and misleading information or between the original and new information with questions that were either explicit or nonexplicit as to the time of the information to be reported. At the 1-week test, children who were exposed to misleading information were significantly less accurate under nonexplicit questioning in recognizing the original from the misleading information than were children presented with consistent information. With explicit questioning, this difference was not significant. When the choice for the children was between original and new items following exposure to delayed misleading postevent information, explicit questioning resulted in significantly more accurate responses at the 7-week test than did nonexplicit questioning. Children questioned explicitly rather than nonexplicitly were more likely to maintain correct responses on both tests. The results are discussed in terms of conversational processes and competing forms of representation in memory retention.

Attention↗
PubMed1996

Theory of mind and pragmatic understanding following right hemisphere damage.

It has been maintained that 3-year-olds' difficulties in correctly predicting the undesired outcome of false beliefs reflects difficulties in interpreting the implications of conversations rather than a conceptual limitation in their theory of mind. As the right hemisphere has been seen to be responsible for the interpretation of the pragmatic aspects of communication, right-hemisphere-damaged (RHD) and left-hemisphere-damaged (LHD) adult patients in our study were compared on their ability to correctly draw inferences in false belief tasks. The RHD but not the LHD patients were found to have difficulties similar to those of young children in understanding the conversational implications test questions. Most reported that a central story character would look for a pet in the place where it was really located instead of where the character believed it was located. However, when then asked in a control question where the pet really was, the RHD patients often switched their answer to the test question and referred to the believed location. Removal of the need to infer the questioner's meaning enabled both RHD and LHD subjects to make correct false belief predictions. The results are discussed in terms of the effects of brain damage on spatial memory and the pragmatic demands of theory of mind tasks.

Adult↗
PubMed1996

Where to look first for suggestibility in young children.

Preschoolers' suggestibility following exposure to biased information has often been interpreted as indicating that memory traces have been genuinely altered. However, young children may not recognize that the purpose and relevance of questions in experiments on suggestibility is to determine whether they can ignore misinformation in remembering the original details of stories. Instead, children may be prompted to regard the original story details as trivial by experimenters who are perceived as having portrayed these details as unimportant or irrelevant in that they themselves did not bother to get these right. Under such conditions, children may interpret the biased information to mean that a biased alternative was an acceptable, or even a preferred, test choice when compared to the original details. We report the results of an investigation with 3- to 5-year-olds in which children heard a story followed the next day by either biased, unbiased, or no information. The children were able to identify the original story details 6 days later when the questions were phrased in an explicit manner that referred to the time of the information to be recalled.

Attention↗
PubMed1995

Deafness, conversation and theory of mind.

The child's developing theory of the mind as an interconnected network of beliefs, desires and feelings that govern behaviour provides a cornerstone for social and intellectual life. Recent research has suggested that autistic children have difficulty acquiring such a theory. Although it is speculated that a specific neurological deficit may be responsible for autistic children's difficulties on false belief tasks devised to test a theory of mind, these may also be due to a lack of exposure to conversation about mental states. In this study we explored the development of a theory of mind in a group of 26 signing, prelingually-deaf Australian children of normal intelligence, aged 8-13 years. Results revealed that 65% of these deaf children failed a simple test of false belief which normal preschoolers, mentally retarded children, and other handicapped groups--apart from children with autism--routinely pass at a mental age of 4-5 years. No significant difference emerged between deaf children's performance and that of autistic children tested on the same task in previous research. We discuss the results in terms of a conversational account of the development of a theory of mind in deaf children, and the extent to which this account is applicable to children with autism.

Adolescent↗
PubMed1994

Reasoning about food and contamination.

This article examines strategies that are used to reason about food and contamination. In Experiment 1, Ss refrained from choosing a substance that had been given a "poison" label when the intent of the labeler was ambiguous or malicious but preferred this substance when a rationale was provided that dispelled the implication that there once might have been contaminants present. Experiment 2 was designed to compare the effects of safety on conditional reasoning in food and food-irrelevant contexts. When the safety issue was relevant to food in the form of contamination, subjects were most likely to use formal logic in reasoning. A similar pattern of responses was found in Experiment 3 on tasks for which subjects' ratings of their experience of contexts were matched for plausibility, experience, and danger. The results are discussed in terms of an adaptive constraint that facilitates rationality in reasoning within the food domain.

Adult↗
PubMed1991

Where to look first for children's knowledge of false beliefs.

Recent research has shown that, although young children have a substantial knowledge of beliefs as internal mental states, they have considerable difficulty in understanding how a false belief can lead to an outcome which is in conflict with a desire. However, this evidence has come from tasks which assume that children follow an experimenter's "implicatures" in conversation and interpret the question "Where will a person (with the false belief) look for the object?" to mean "Where will the person look first?" rather than "Where will the person have to look (or go to look) to find the object?" In our investigation, even 3-year-olds often responded correctly when asked to predict the initial behavior of a story character with a false belief. We discuss these results in terms of the conversational worlds of children and adults.

Adult↗
PubMed1991

Antiarrhythmic actions of the ATP-regulated K+ current activated by pinacidil.

We tested the hypothesis that a selective increase in membrane current, as contrasted with the decreases in currents caused by most antiarrhythmic agents, would be an effective antiarrhythmic intervention. We studied models of early afterdepolarizations (EADs), delayed afterdepolarizations (DADs), and abnormal automaticity in single canine ventricular myocytes using intracellular microelectrodes or patch electrodes. EADs were induced by injected current, Bay K 8644 (0.5-1 microM), or ketanserin (1.0 microM); DADs were induced by ouabain intoxication (2 x 10(-7) M); and abnormal automaticity was induced by exposure to barium (0.25 mM). To increase outward K+ current, we used pinacidil and the protein kinase C activator 4 beta-phorbol 12,13-dibutyrate (PDBu). Under control conditions, 10-100 microM pinacidil caused a concentration-dependent and reversible decrease in action potential duration and an increase in steady-state outward current; both effects were blocked by glibenclamide and thus presumably reflected changes in the ATP-regulated potassium current. Pinacidil increased the current required to induce EADs and abolished EADs caused by Bay K 8644 or ketanserin. After exposure of myocytes to ouabain, pinacidil caused a decrease in action potential duration and diminished or abolished DADs. Finally, pinacidil arrested abnormal automaticity caused by Ba2+. PDBu (30 nM) shortened action potential duration without altering plateau amplitude in some of the myocytes. In these cells the depolarizing current needed to produce an EAD was increased by over 70%; outward potassium current tails were also increased, an effect consistent with an increase of the repolarizing potassium current (IK). These findings show that each of the mechanisms for abnormal impulse generation can be effectively antagonized by an increase in outward current and suggest to us that selective augmentation of a repolarizing current, possibly IK, might be a reasonable antiarrhythmic intervention.

Action Potentials↗
PubMed1991

Counting by children with Down syndrome.

Children's understanding of one-to-one, stable order, and cardinal principles was tested through error-detection and self-performance counting tasks. Gelman's modified counting task was used to test understanding of the order irrelevance principle. There were no significant differences between the mean task scores of 15 children with Down syndrome and 15 preschoolers with similar revised Peabody Picture Vocabulary test (PPVT-R) scores (mean age equivalent, 4 years, 7 months). Partial correlations showed several significant associations between counting principles and PPVT-R that were independent of chronological age. The results support the view that counting by children with Down syndrome can be guided by counting principles and that developmental level rather than the syndrome is associated with counting behavior.

Attention↗
PubMed1988

Children's knowledge of contagion and contamination as causes of illness.

Children's knowledge of contagion and contamination as causes of illness was examined in 3 experiments. In Experiment 1, preschoolers and children in grades 1 and 3 were shown videotaped segments of puppets with colds and toothaches who explained their ailments in terms of contagion and immanent justice. The children were instructed to evaluate and correct the puppets' explanations and, in addition, to indicate the possible effects on health of drinking milk that had come into contact with objects such as a cockroach, used comb, and spoon. Even preschoolers displayed some knowledge of contagion and contamination. However, compared to the third graders, younger children were less likely to reject proximity to a sick person and naughty behavior as causes of toothaches. They were also more likely to indicate that to drink milk that had come into contact with a spoon was unhealthy. In Experiment 2, preschoolers rejected the proposition that an ailment caused by accident (i.e., a scraped knee) is contagious and, in Experiment 3, they generally accepted that contamination through contact with a dirty spoon can be prevented by washing. Altogether, preschoolers have a more substantial knowledge of contagion and contamination than has been estimated previously. The results are discussed in terms of children's ability to understand causal relations.

Accidents↗
PubMed1984

Diminished responsibility as a mitigating circumstance in juvenile offenders' legal judgments.

The legal judgments of 20 juvenile offenders and 20 non-offenders were examined for three types of crimes: assault, arson and treason. Mitigating circumstances cast in the form of an inability to control events consisted of brain damage, passion and economic need, in contrast to a situation in which no mitigating circumstances were offered. The results indicated that despite the often-made legal argument, neither group regarded passion and economic need as circumstances warranting the reduction of sentencing. Compared to the non-offender group, offenders rated brain damage as less mitigating. While non-offenders rated passion and economic need more severely than brain damage, offenders' ratings of the three circumstances did not differ significantly. The findings are discussed in terms of perceptions of control and structural-developmental approaches to socialization.

Adolescent↗