47 Result(s)
within
William G. Iacono
Psychology
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Article
Eye tracking in normal twins
The influence of genetic factors on smooth-pursuit and saccadic eye tracking was determined using 34 pairs of monozygotic and 24 pairs of dizygotic twins. Subjects engaged in smooth-pursuit tracking of differe...
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The effects of instructions and an engaging visual task on habituation to loud tones: An evaluation of an alternative to the traditional habituation paradigm
The effects of ambiguous instructions and instructions to specifically ignore or attend to stimuli on electrodermal habituation were examined in 88 volunteers who were evenly divided among four groups. The sub...
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Selected Psychophysiological Measures in Depression: The Significance of Electrodermal Activity, Electroencephalographic Asymmetries, and Contingent Negative Variation to Behavioral and Neurobiological Aspects of Depression
Although the phenomenon of depression has been described in one form or another since the time of Hippocrates, major advances in understanding the etiology, course, and treatment of depression have come only r...
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Unequal rate of monozygotic and like-sex dizygotic twin birth: Evidence from the Minnesota twin family study
It is generally believed that in Caucasian populations the rate of monozygotic (MZ) twinning is approximately equal to the rate of like-sex dizygotic (DZ) twinning so that representative samples of like-sex tw...
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Life events and personality in late adolescence: Genetic and environmental relations
The relationship between life events and personality was investigated in the Minnesota Twin/Family Study, using 216 monozygotic and 114 dizygotic 17-year-old male twin pairs. Participants completed a life even...
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Searching for Interactive Effects in the Etiology of Early-Onset Substance Use
This study sought to expand the modest literature investigating gene × environment interactions in the prediction of substance use. Our sample consisted of 591 male twins from the Minnesota Twin Family Study. ...
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Physical Similarity and Twin Resemblance for Eating Attitudes and Behaviors: A Test of the Equal Environments Assumption
The Equal Environments Assumption (EEA) in twin studies of eating pathology was investigated by examining the hypothesis that twin resemblance for eating attitudes and behaviors is affected by their degree of ...
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Genetic and Environmental Influences on Psychopathy Trait Dimensions in a Community Sample of Male Twins
Psychopathy appears to be comprised of two broad dimensions: impulsivity/antisocial behavior and interpersonal detachment/callousness. This study examined the extent to which variance in these 2 psychopathy tr...
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Genetic and Environmental Influences on Adolescents’ Perceptions of Current Family Environment
Previous studies of the genetic and environmental components of the Family Environment Scale (FES) have typically reported that scales relating to familial acceptance are moderately to strongly genetically inf...
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The Association of Early Adolescent Problem Behavior and Adult Psychopathology: A Multivariate Behavioral Genetic Perspective
Research has documented a strong association between early adolescent problem behavior and adult disinhibitory psychopathology, leading some to suggest that the latter can be reduced by preventing or delaying ...
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The Environments of Adopted and Non-adopted Youth: Evidence on Range Restriction From the Sibling Interaction and Behavior Study (SIBS)
Previous reviews of the literature have suggested that shared environmental effects may be underestimated in adoption studies because adopted individuals are exposed to a restricted range of family environment...
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Environmental Contributions to Adolescent Delinquency: A Fresh Look at the Shared Environment
Few genetically-informative studies have attempted to explicitly identify the shared environmental (i.e., those environmental influences that contribute to sibling similarity) factors now known to contribute to a...
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Construct Validity of Adolescent Antisocial Personality Disorder
This study examined the construct validity of antisocial personality disorder (ASPD) diagnosed in adolescence. Boys and girls were grouped by history of DSM-III-R conduct disorder (CD) and ASPD: Controls (n=340) ...
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A Twin Study of the Genetics of High Cognitive Ability Selected from 11,000 Twin Pairs in Six Studies from Four Countries
Although much genetic research has addressed normal variation in intelligence, little is known about the etiology of high cognitive abilities. Using data from 11,000 twin pairs (age range = 6–71 years) from th...
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Shared-Environmental Contributions to High Cognitive Ability
Using a combined sample of adolescent twins, biological siblings, and adoptive siblings, we estimated and compared the differential shared-environmentality for high cognitive ability and the shared-environment...
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Are there Shared Environmental Influences on Adolescent behavior? Evidence from a Study of Adoptive Siblings
The failure to identify specific non-shared environmental influences on behavior coupled with the belief that shared environmental factors contribute minimally to individual differences in behavior has led to ...
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Brain Electrophysiological Endophenotypes for Externalizing Psychopathology: A Multivariate Approach
Abnormalities in electrophysiological measures of stimulus-evoked brain activity (including the P3 event-related potential (ERP) and its associated delta and theta time–frequency (TF) components), and intrinsi...
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Environmental Contributions to the Stability of Antisocial Behavior over Time: Are They Shared or Non-shared?
It has recently been argued that shared environmental influences are moderate, identifiable, and persistent sources of individual differences in most forms of child and adolescent psychopathology, including an...
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Harsh Discipline, Childhood Sexual Assault, and MAOA Genotype: An Investigation of Main and Interactive Effects on Diverse Clinical Externalizing Outcomes
We studied the impact of MAOA genotype, childhood sexual assault, and harsh discipline on clinical externalizing symptoms (substance problems, adult antisocial behavior, and conduct disorder). Participants wer...
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Psychometric and Genetic Architecture of Substance Use Disorder and Behavioral Disinhibition Measures for Gene Association Studies
Using large twin, family, and adoption studies conducted at the Minnesota Center for Twin and Family Research, we describe our efforts to develop measures of substance use disorder (SUD) related phenotypes for...
