Localization of deformations within the amygdala in individuals with psychopathy.
ABSTRACT Despite the repeated findings of impaired fear conditioning and affective recognition in psychopathic individuals, there has been a paucity of brain imaging research on the amygdala and no evidence suggesting which regions within the amygdala may be structurally compromised in individuals with psychopathy.
To detect global and regional anatomical abnormalities in the amygdala in individuals with psychopathy.
Cross-sectional design using structural magnetic resonance imaging.
Participants were recruited from high-risk communities (temporary employment agencies) in the Los Angeles, California, area and underwent imaging at a hospital research facility at the University of Southern California.
Twenty-seven psychopathic individuals as defined by the Hare Psychopathy Checklist-Revised and 32 normal controls matched on age, sex, and ethnicity.
Amygdala volumes were examined using traditional volumetric analyses and surface-based mesh modeling methods were used to localize regional surface deformations.
Individuals with psychopathy showed significant bilateral volume reductions in the amygdala compared with controls (left, 17.1%; right, 18.9%). Surface deformations were localized in regions in the approximate vicinity of the basolateral, lateral, cortical, and central nuclei of the amygdala. Significant correlations were found between reduced amygdala volumes and increased total and facet psychopathy scores, with correlations strongest for the affective and interpersonal facets of psychopathy.
Results provide the first evidence, to our knowledge, of focal amygdala abnormalities in psychopathic individuals and corroborate findings from previous lesion studies. Findings support prior hypotheses of amygdala deficits in individuals with psychopathy and indicate that amygdala abnormalities contribute to emotional and behavioral symptoms of psychopathy.
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ABSTRACT: Dysfunction in the prefrontal cortex, amygdala, and hippocampus is believed to underlie the development of much psychopathology. However, to date only limited longitudinal data relate early behavior with neural structure later in life. Our objective was to examine the relationship of early life externalizing behavior with adolescent brain structure. We report here the first lon-gitudinal study linking externalizing behavior during preschool to brain structure during ado-lescence. We examined the relationship of preschool externalizing behavior with amygdala, hippocampus, and prefrontal cortex volumes at age 15 years in a community sample of 76 ad-olescents followed longitudinally since their mothers' pregnancy. A significant gender by ex-ternalizing behavior interaction revealed that males—but not females—with greater early childhood externalizing behavior had smaller amygdala volumes at adolescence (t = 2.33, p = .023). No significant results were found for the hippocampus or the prefrontal cortex. Greater early externalizing behavior also related to smaller volume of a cluster including the angular gyrus and tempoparietal junction across genders. Results were not attributable to the impact of preschool anxiety, preschool maternal stress, school-age internalizing or externaliz-ing behaviors, or adolescent substance use. These findings demonstrate a novel, gender-specific relationship between early-childhood externalizing behavior and adolescent amygda-la volume, as well as a cross-gender result for the angular gyrus and tempoparietal junction.PLoS ONE 02/2015; 10(2):e0117453. DOI:10.1371/journal.pone.0117453 · 3.53 Impact Factor
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ABSTRACT: En este trabajo se propone identificar posibles marcadores neurobiológicos que contribuyan a la propuesta de un modelo explicativo de la génesis del Trastorno de Personalidad Antisocial (TPA) y la psicopatía. Estos neuromarcadores incluyen las alteraciones morfofuncionales detectadas a través del análisis del Electroencefalograma (EEG) y del grosor cortical calculado a partir de las imágenes de Resonancia Magnética Nuclear (RMN). En el diseño del estudio se tuvo en cuenta dos limitaciones de estudios previos. Primero, la caracterización adecuada de las muestras de sujetos violentos mediante criterios y escalas estandarizadas, para el diagnóstico de TPA y psicopatía. Segundo, la selección de muestras controles, integradas por individuos violentos que se encuentren en prisión, sin TPA, ni psicopatía. Este trabajo se extendió al estudio de la población de mujeres reas violentas. Así como, propone otros parámetros descriptores del funcionamiento cerebral, con la inclusión del análisis cuantitativo del EEG (EEGq). Los resultados demostraron diferencias entre los reos violentos con y sin diagnóstico psiquiátrico, tanto para TPA como la psicopatía. El patrón de las anomalías difirió entre mujeres y hombres psicópatas. Los sujetos violentos con TPA y psicopatía presentan un déficit en el procesamiento emocional, dado el patrón de anomalías identificadas en el circuito paralímbico. El EEG y la RMN estructural, fueron útiles para identificar posibles neuromarcadores, asociados con estas entidades psicopatológicas.07/2014, Degree: PhD, Supervisor: Alfredo Alvarez Amador
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ABSTRACT: P sychopathy is a serious per-sonality disorder that can have significant negative effects both on individuals and on society. 1 Psychopathy was first described by Hervey M. Cleckley in his classic book The Mask of San-ity, published in 1941 and still used today for its detailed case studies of psychopathy. 2 Psychopathy occurs worldwide and in all age groups, cultures, and ethnic groups, with a predominance in males. Although it is difficult to determine a precise figure, psychopaths constitute approximately 1% to 4% of the population. Psychopathy should not be con-fused with psychosis. Psychopaths can clearly distinguish reality from fantasy, although their view of the world differs significantly from that of the rest of society. The public perception of the psychopath is usu-ally that of a maniacal serial killer; however, many psychopaths do not commit crimes and they mingle freely in society. Psychopaths con-stitute a sizable share of the prison population (approximately 20%), however, and they are more likely than nonpsychopathic criminals to reoffend. 3U. S. pharmacist 11/2014; 39:485-495.