RESUMEN
Early childhood neglect can impact brain development across the lifespan. Using voxel-based approaches we recently reported that severe and time-limited institutional deprivation in early childhood was linked to substantial reductions in total brain volume in adulthood, >20 years later. Here, we extend this analysis to explore deprivation-related regional white matter volume and microstructural organization using diffusion-based techniques. A combination of tensor-based morphometry (TBM) analysis and tractography was conducted on diffusion-weighted imaging (DWI) data from 59 young adults who spent between 3 and 41 months in the severely depriving Romanian institutions of the 1980s before being adopted into United Kingdom families, and 20 nondeprived age-matched United Kingdom controls. Independent of total volume, institutional deprivation was associated with smaller volumes in localized regions across a range of white matter tracts including (1) long-ranging association fibers such as bilateral inferior longitudinal fasciculus (ILF), bilateral inferior fronto-occipital fasciculus (IFOF), left superior longitudinal fasciculi (SLFs), and left arcuate fasciculus; (2) tracts of the limbic circuitry including fornix and cingulum; and (3) projection fibers with the corticospinal tract particularly affected. Tractographic analysis found no evidence of altered microstructural organization of any tract in terms of hindrance modulated orientational anisotropy (HMOA), fractional anisotropy (FA), or mean diffusivity (MD). We provide further evidence for the effects of early neglect on brain development and their persistence in adulthood despite many years of environmental enrichment associated with successful adoption. Localized white matter effects appear limited to volumetric changes with microstructural organization unaffected.
Asunto(s)
Sustancia Blanca , Humanos , Preescolar , Adulto Joven , Adulto , Sustancia Blanca/diagnóstico por imagen , Imagen de Difusión Tensora/métodos , Estudios Prospectivos , Anisotropía , Encéfalo/diagnóstico por imagenRESUMEN
BACKGROUND: Institutional deprivation in early childhood is associated with neuropsychological deficits in adolescence. Using 20-year follow-up data from a unique natural experiment - the large-scale adoption of children exposed to extreme deprivation in Romanian institutions in the 1980s -we examined, for the first time, whether such deficits are still present in adulthood and whether they are associated with deprivation-related symptoms of attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). METHODS: Adult neuropsychological functioning was assessed across five domains (inhibitory control, emotion recognition, decision-making, prospective memory and IQ) in 70 previously institutionalized adoptees (mean age = 25.3, 50% female) and 22 non-deprived UK adoptees (comparison group, mean age = 24.6, 41% female). ADHD and ASD symptoms were assessed using parent-completed questionnaires. RESULTS: Early institutionalization was associated with impaired performance on all tasks in adulthood. Prospective memory deficits persisted after controlling for IQ. ADHD and ASD symptoms were positively correlated. After controlling for ASD symptoms, ADHD symptoms remained associated with deficits in IQ, prospective memory, proactive inhibition, decision-making quality and emotion recognition. ASD symptoms were not independently associated with neuropsychological deficits when accounting for their overlap with ADHD symptoms. Multiple regression analysis revealed that the link between childhood deprivation and adult ADHD symptoms was statistically explained by deprivation-related differences in adult IQ and prospective memory. CONCLUSIONS: These results represent some of the most compelling evidence to date of the enduring power of early, time-limited childhood adversity to impair long-term neuropsychological functioning across the lifespan - effects that are linked specifically to deprivation-related adult ADHD symptoms.
Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Trastornos de la Memoria/psicología , Carencia Psicosocial , Adulto , Niño Adoptado , Femenino , Estudios de Seguimiento , Humanos , Inteligencia , Masculino , Pruebas Neuropsicológicas , Rumanía/etnología , Reino Unido , Adulto JovenRESUMEN
Early childhood deprivation is associated with higher rates of neurodevelopmental and mental disorders in adulthood. The impact of childhood deprivation on the adult brain and the extent to which structural changes underpin these effects are currently unknown. To investigate these questions, we utilized MRI data collected from young adults who were exposed to severe deprivation in early childhood in the Romanian orphanages of the CeauÈescu era and then, subsequently adopted by UK families; 67 Romanian adoptees (with between 3 and 41 mo of deprivation) were compared with 21 nondeprived UK adoptees. Romanian adoptees had substantially smaller total brain volumes (TBVs) than nondeprived adoptees (8.6% reduction), and TBV was strongly negatively associated with deprivation duration. This effect persisted after covarying for potential environmental and genetic confounds. In whole-brain analyses, deprived adoptees showed lower right inferior frontal surface area and volume but greater right inferior temporal lobe thickness, surface area, and volume than the nondeprived adoptees. Right medial prefrontal volume and surface area were positively associated with deprivation duration. No deprivation-related effects were observed in limbic regions. Global reductions in TBV statistically mediated the observed relationship between institutionalization and both lower intelligence quotient (IQ) and higher levels of attention deficit/hyperactivity disorder symptoms. The deprivation-related increase in right inferior temporal volume seemed to be compensatory, as it was associated with lower levels of attention deficit/hyperactivity disorder symptoms. We provide compelling evidence that time-limited severe deprivation in the first years of life is related to alterations in adult brain structure, despite extended enrichment in adoptive homes in the intervening years.
Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/patología , Encéfalo/patología , Desarrollo Infantil/fisiología , Niño Institucionalizado/psicología , Carencia Psicosocial , Adopción , Adulto , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/etiología , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Inteligencia , Pruebas de Inteligencia , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Tamaño de los Órganos , Orfanatos , Estudios Prospectivos , Rumanía , Factores de Tiempo , Reino Unido , Adulto JovenRESUMEN
Many empathy tasks lack ecological validity due to their use of simplistic stimuli and static analytical approaches. Empathic accuracy tasks overcome these limitations by using autobiographical emotional video clips. Usually, a single measure of empathic accuracy is computed by correlating the participants' continuous ratings of the narrator's emotional state with the narrator's own ratings. In this study, we validated a modified empathic accuracy task. A valence-independent rating of the narrator's emotional intensity was added to provide comparability between videos portraying different primary emotions and to explore changes in neural activity related to variations in emotional intensity over time. We also added a new neutral control condition to investigate general emotional processing. In the scanner, 34 healthy participants watched 6 video clips of people talking about an autobiographical event (2 sad, 2 happy and 2 neutral clips) while continuously rating the narrator's emotional intensity. Fluctuation in perceived emotional intensity correlated with activity in brain regions previously implicated in cognitive empathy (bilateral superior temporal sulcus, temporoparietal junction, and temporal pole) and affective empathy (right anterior insula and inferior frontal gyrus). When emotional video clips were compared to neutral video clips, we observed higher activity in similar brain regions. Empathic accuracy, on the other hand, was only positively related to activation in regions that have been implicated in cognitive empathy. Our modified empathic accuracy task provides a new method for studying the underlying components and dynamic processes involved in empathy. While the task elicited both cognitive and affective empathy, successful tracking of others' emotions relied predominantly on the cognitive components of empathy. The fMRI data analysis techniques developed here may prove valuable in characterising the neural basis of empathic difficulties observed across a range of psychiatric conditions.
Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Emociones/fisiología , Empatía/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Adulto JovenRESUMEN
We recently reported that emotional detachment in adult psychopathy was associated with structural abnormalities in the dorsal 'default-mode' network (DMN). However, it is unclear whether these differences are present in young people at risk of psychopathy. The most widely recognised group at risk for psychopathy are children/adolescents with conduct disorder (CD) and callous-unemotional (CU) traits. We therefore examined the microstructure of the dorsal DMN in 27 CD youths (14-with/13-without CU traits) compared to 16 typically developing controls using DTI tractography. Both CD groups had significantly (pâ¯<â¯0.025) reduced dorsal DMN radial diffusivity compared to controls. In those with diagnostically significant CU traits, exploratory analyses (uncorrected for multiple comparisons) suggested that radial diffusivity was negatively correlated with CU severity (Left: rhoâ¯=â¯-0.68, pâ¯=â¯0.015). These results suggest that CD youths have microstructural abnormalities in the same network as adults with psychopathy. Further, the association with childhood/adolescent measures of emotional detachment (CU traits) resembles the relationship between emotional detachment and network microstructure in adult psychopaths. However, these changes appear to occur in opposite directions - with increased myelination in adolescent CD but reduced integrity in adult psychopathy. Collectively, these findings suggest that developmental abnormalities in dorsal DMN may play a role in the emergence of psychopathy.
Asunto(s)
Síntomas Afectivos/diagnóstico por imagen , Trastorno de la Conducta/diagnóstico por imagen , Giro del Cíngulo/anatomía & histología , Giro del Cíngulo/diagnóstico por imagen , Red Nerviosa/anatomía & histología , Red Nerviosa/diagnóstico por imagen , Adolescente , Síntomas Afectivos/psicología , Niño , Trastorno de la Conducta/psicología , Imagen de Difusión Tensora/métodos , Humanos , MasculinoRESUMEN
BACKGROUND: The biological basis of severe antisocial behaviour in adolescents is poorly understood. We recently reported that adolescents with conduct disorder (CD) have significantly increased fractional anisotropy (FA) of the uncinate fasciculus (a white matter (WM) tract that connects the amygdala to the frontal lobe) compared to their non-CD peers. However, the extent of WM abnormality in other brain regions is currently unclear. METHODS: We used tract-based spatial statistics to investigate whole brain WM microstructural organisation in 27 adolescent males with CD, and 21 non-CD controls. We also examined relationships between FA and behavioural measures. Groups did not differ significantly in age, ethnicity, or substance use history. RESULTS: The CD group, compared to controls, had clusters of significantly greater FA in 7 brain regions corresponding to: 1) the bilateral inferior and superior cerebellar peduncles, corticopontocerebellar tract, posterior limb of internal capsule, and corticospinal tract; 2) right superior longitudinal fasciculus; and 3) left cerebellar WM. Severity of antisocial behavior and callous-unemotional symptoms were significantly correlated with FA in several of these regions across the total sample, but not in the CD or control groups alone. CONCLUSIONS: Adolescents with CD have significantly greater FA than controls in WM regions corresponding predominantly to the fronto-cerebellar circuit. There is preliminary evidence that variation in WM microstructure may be dimensionally related to behaviour problems in youngsters. These findings are consistent with the hypothesis that antisocial behaviour in some young people is associated with abnormalities in WM 'connectivity'.
Asunto(s)
Mapeo Encefálico/métodos , Trastorno de la Conducta/diagnóstico , Sustancia Blanca/patología , Adolescente , Conducta del Adolescente , Anisotropía , Trastorno de Personalidad Antisocial/diagnóstico , Trastorno de Personalidad Antisocial/patología , Estudios de Casos y Controles , Niño , Trastorno de la Conducta/patología , Imagen de Difusión Tensora , Consumidores de Drogas/psicología , Humanos , Masculino , Sustancia Blanca/diagnóstico por imagen , Adulto JovenRESUMEN
Children with conduct disorder (CD) are at increased risk of developing antisocial personality disorder and psychopathy in adulthood. Neuroimaging research has identified abnormal cortical volume (CV) in CD. However, CV comprises two genetically and developmentally separable components: cortical thickness (CT) and surface area (SA). Aim of this study is to explore the relationship between the cortical constituents of CV in boys with CD. We applied FreeSurfer software to structural MRI data to derive measures of CV, CT, and SA in 21 boys with CD and 19 controls. Relationships between these cortical measures were investigated. Boys with CD had significantly reduced CV and SA compared to non-CD boys in ventromedial and dorsolateral prefrontal cortex. We found no significant between-group differences in CT. Reduced prefrontal CV in boys with CD is associated with significantly reduced SA in the same regions. This finding may help to identify specific neurodevelopmental mechanisms underlying cortical deficits observed in CD.
Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno de la Conducta/patología , Imagen por Resonancia Magnética/métodos , Corteza Prefrontal/patología , Adolescente , Trastorno de Personalidad Antisocial , Atención , Estudios de Casos y Controles , Niño , Trastorno de la Conducta/psicología , Humanos , Masculino , Encuestas y Cuestionarios , Adulto JovenRESUMEN
OBJECTIVES: Maternal prenatal stress is associated with elevated risk of adverse behavioural outcomes in offspring. This association may involve developmental disruption to limbic-prefrontal white matter circuitry, of which the uncinate fasciculus is the major tract. One potential candidate for modulating brain development is maternal prenatal stress. We provide the first prospective study of prenatal stress and white matter microstructure in children. METHODS: A total of 22 healthy children (mean age 7 years) of mothers recruited in pregnancy underwent diffusion tensor magnetic resonance imaging. We examined correlations between prenatal stressful life events and white matter microstructural organisation indices (fractional anisotropy (FA) and perpendicular diffusivity (Dperp)) of the uncinate fasciculus and a "control" tract. RESULTS: Maternal prenatal stressful life events were correlated positively with right uncinate fasciculus FA, and negatively with right uncinate fasciculus Dperp in their child, with a similar trend with left uncinate fasciculus Dperp. Prenatal stress was not associated with control tract properties; sociodemographic/obstetric variables were not associated with FA/Dperp of either tract. CONCLUSIONS: Variation in maternal prenatal stress may be associated with differences in the development of white matter within brain networks underlying child social behaviour.
Asunto(s)
Encéfalo/patología , Imagen de Difusión Tensora/métodos , Red Nerviosa/patología , Complicaciones del Embarazo/psicología , Efectos Tardíos de la Exposición Prenatal/patología , Estrés Psicológico/complicaciones , Adulto , Niño , Imagen de Difusión Tensora/instrumentación , Femenino , Lóbulo Frontal/patología , Humanos , Acontecimientos que Cambian la Vida , Sistema Límbico/patología , Embarazo , Sustancia Blanca/patologíaRESUMEN
Little is known about how sex influences functional brain maturation. The current study investigated sex differences in the maturation of event-related potential (ERP) amplitudes during an auditory oddball task (N = 170; age = 6-17 years). Performance improved with age. N200 amplitude declined with age: parietal sites showed earlier development than temporal and frontal locations. Girls showed greater bilateral frontal P300 amplitude development, approaching the higher values observed in boys during childhood. After controlling for age, right frontal P300 amplitude was associated with reaction time in girls. The findings demonstrate sex differences in ERP maturation in line with behavioral and neuroimaging studies.
Asunto(s)
Envejecimiento/fisiología , Percepción Auditiva/fisiología , Encéfalo/fisiología , Potenciales Evocados/fisiología , Caracteres Sexuales , Estimulación Acústica , Adolescente , Encéfalo/crecimiento & desarrollo , Mapeo Encefálico , Niño , Preescolar , Electroencefalografía , Femenino , Humanos , Masculino , Tiempo de Reacción/fisiologíaRESUMEN
UNLABELLED: Antisocial personality disorder (ASPD) and psychopathy involve significant interpersonal and behavioural impairments. However, little is known about their underlying neurobiology and in particular, abnormalities in white matter (WM) microstructure. A preliminary diffusion tensor magnetic resonance imaging (DT-MRI) study of adult psychopaths employing tractography revealed abnormalities in the right uncinate fasciculus (UF) (Craig et al., 2009), indicating fronto-limbic disconnectivity. However, it is not clear whether WM abnormalities are restricted to this tract or are or more widespread, including other tracts which are involved in connectivity with the frontal lobe. We performed whole brain voxel-based analyses on WM fractional anisotropy (FA) and mean diffusivity (MD) maps acquired with DT-MRI to compare 15 adults with ASPD and healthy age, handedness and IQ-matched controls. Also, within ASPD subjects we related differences in FA and MD to measures of psychopathy. Significant WM FA reduction and MD increases were found respectively in ASPD subjects relative to controls. FA was bilaterally reduced in the genu of corpus callosum while in the right frontal lobe FA reduction was found in the UF, inferior fronto-occipital fasciculus (IFOF), anterior corona radiata and anterior limb and genu of the internal capsule. These differences negatively correlated with measures of psychopathy. Also in the right frontal lobe, increased MD was found in the IFOF and UF, and the corpus callosum and anterior corona radiata. There was a significant positive correlation between MD and psychopathy scores. CONCLUSIONS: The present study confirms a previous report of reduced FA in the UF. Additionally, we report for the first time, FA deficits in tracts involved in interhemispheric as well as frontal lobe connectivity in conjunction with MD increases in the frontal lobe. Hence, we provide evidence of significant WM microstructural abnormalities in frontal brain regions in ASPD and psychopathy.