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1.
Dev Neuropsychol ; 36(1): 118-35, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21253994

RESUMEN

This study investigated the association between different neonatal ultrasonographic classifications and adolescent cognitive, educational, and behavioral outcomes following very preterm birth. Participants included a group of 120 adolescents who were born very preterm (<33 weeks of gestation), subdivided into three groups according to their neonatal cerebral ultrasound (US) classifications: (a) normal (N = 69), (b) periventricular hemorrhage (PVH, N = 37), and (c) PVH with ventricular dilatation (PVH + DIL, N = 14), and 50 controls. The cognitive functions assessed were full-scale IQ, phonological and semantic verbal fluency, and visual-motor integration. Educational outcomes included reading and spelling; behavioral outcomes were assessed with the Rutter Parents' Scale and the Premorbid Adjustment Scale (PAS). Adolescent outcome scores were compared among the four groups. A main effect for group was observed for full-scale IQ, Rutter Parents' Scale total scores, and PAS total scores, after controlling for gestational age, socioeconomic status and gender, with the PVH + DIL group showing the most impaired scores compared to the other groups. The current results demonstrate that routine neonatal ultrasound classifications are associated with later cognitive and behavioral outcome. Neonatal ultrasounds could aid in the identification of subgroups of children who are at increased risk of neurodevelopmental problems. These at risk subgroups could then be referred to appropriate early intervention services.


Asunto(s)
Conducta del Adolescente , Trastornos del Conocimiento/diagnóstico por imagen , Trastornos del Conocimiento/etiología , Discapacidades del Desarrollo/complicaciones , Nacimiento Prematuro/diagnóstico por imagen , Nacimiento Prematuro/fisiopatología , Adolescente , Factores de Edad , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Discapacidades del Desarrollo/diagnóstico por imagen , Femenino , Edad Gestacional , Humanos , Pruebas de Inteligencia , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Desempeño Psicomotor , Lectura , Estadísticas no Paramétricas , Ultrasonografía/métodos
2.
Pharmacopsychiatry ; 44(1): 33-48, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21154218

RESUMEN

INTRODUCTION: Misattribution of distorted self-generated speech in patients with schizophrenia has been associated with increased lateral temporal activation. As a pharmacological model of schizophrenia, we tested whether ketamine would induce the same effects in healthy individuals. METHODS: Participants were 8 healthy male volunteers who were naïve to ketamine (mean age: 28 years). Ketamine (0.23 mg/kg bolus followed by 0.64 mg/kg/h) and placebo infusions were administered in a double-blind, randomised order, during 2 functional magnetic resonance imaging (fMRI) sessions. Each fMRI session consisted of a verbal self-monitoring task in which auditory feedback was experimentally modified. RESULTS: Ketamine was associated with psychotic and dissociative symptoms. Participants made more misattributions of distorted self-generated speech (P < 0.02) during the ketamine infusion. Ketamine led to reduced activation in the left superior temporal cortex during self-distorted speech, regardless of whether the speech was identified correctly or not, as compared to the placebo infusion. Misidentification of speech that had been distorted was not associated with any increase in brain activation in during the placebo infusion, however ketamine-induced misattributions were associated with a relative increase in left superior temporal cortex activation. DISCUSSION: These data are consistent with the notion that self-monitoring impairments underlie psychotic symptoms and suggest that N-methyl-D-aspartate (NMDA) receptor dysfunction may mediate self-monitoring deficits and psychotic phenomena in schizophrenia.


Asunto(s)
Ketamina/farmacología , Psicosis Inducidas por Sustancias/etiología , Lóbulo Temporal/efectos de los fármacos , Conducta Verbal/efectos de los fármacos , Adulto , Método Doble Ciego , Retroalimentación Psicológica/efectos de los fármacos , Humanos , Ketamina/efectos adversos , Imagen por Resonancia Magnética , Masculino , Trastornos Psicóticos
3.
J Int Neuropsychol Soc ; 16(4): 716-20, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20441689

RESUMEN

Reduced posterior corpus callosum (CC) area has been consistently observed in children and adolescents born very preterm (VPT). CC structural differences are also observed in people diagnosed with empathy disorders. This study examined empathy in relation to CC size in VPT adults and controls. CC area was manually measured for 17 VPT adults and 9 controls. Participants completed the Interpersonal Reactivity Index (Davis, 1980) and the Empathy Quotient (Baron-Cohen & Wheelwright, 2004). VPT adults had reduced posterior CC area in contrast to controls, and a positive linear trend was observed between posterior CC size and gestational age. No between-group empathy differences were observed, although self-reported personal distress in response to social situations was higher in VPT adults, and negatively associated with anterior CC area. We conclude that VPT adults have a smaller posterior CC, which is associated with gestational age, and elevated social distress, which may be mediated by anterior CC size.


Asunto(s)
Cuerpo Calloso/patología , Empatía/fisiología , Nacimiento Prematuro/patología , Nacimiento Prematuro/psicología , Adolescente , Análisis de Varianza , Cuerpo Calloso/crecimiento & desarrollo , Femenino , Edad Gestacional , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Pruebas Neuropsicológicas , Adulto Joven
4.
Psychol Med ; 40(12): 2025-35, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20146832

RESUMEN

BACKGROUND: Individuals with a history of bipolar disorder demonstrate abnormalities of executive function, even during euthymia. The neural architecture underlying this and its relationship with genetic susceptibility for illness remain unclear. METHOD: We assessed 18 remitted individuals with bipolar disorder, 19 of their unaffected first degree relatives and 19 healthy controls using functional magnetic resonance imaging (fMRI) and a paced verbal fluency task with two levels of difficulty. RESULTS: Bipolar patients made significantly more errors in the easy level of the verbal fluency task than their relatives or controls. Analysis of variance of fMRI data demonstrated a significant main effect of group in a large cluster including retrosplenial cortex and adjacent precuneate cortex (x=7, y=-56, x=15). All three groups showed deactivation in these areas during task performance relative to a neutral or rest condition. Group differences comprised a lesser amount of deactivation in unaffected relatives compared with controls in the easy condition [F(2, 55)=3.42, p=0.04] and in unaffected relatives compared with bipolar patients in the hard condition [F(2, 55)=4.34, p=0.018]. Comparison with the control group indicated that both bipolar patients and their relatives showed similar deficits of deactivation in retrosplenial cortex and reduced activation of left prefrontal cortex. CONCLUSIONS: Bipolar disorder may be associated with an inherited abnormality of a neural network incorporating left prefrontal cortex and bilateral retrosplenial cortex.


Asunto(s)
Trastorno Bipolar/genética , Trastorno Bipolar/fisiopatología , Imagen por Resonancia Magnética , Corteza Prefrontal/fisiopatología , Trastornos del Habla/etiología , Adulto , Trastorno Bipolar/complicaciones , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatología , Análisis y Desempeño de Tareas , Conducta Verbal
6.
Psychol Med ; 39(11): 1783-97, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19573260

RESUMEN

BACKGROUND: Morphometric endophenotypes which have been proposed for psychotic disorders include lateral ventricular enlargement and hippocampal volume reductions. Genetic epidemiological studies support an overlap between schizophrenia and bipolar disorder, and COMT, BDNF, 5-HTT, NRG1 and DTNBP1 genes have been implicated in the aetiology of both these disorders. This study examined associations between these candidate genes and morphometric endophenotypes for psychosis. METHOD: A total of 383 subjects (128 patients with psychosis, 194 of their unaffected relatives and 61 healthy controls) from the Maudsley Family Psychosis Study underwent structural magnetic resonance imaging and genotyping. The effect of candidate genes on brain morphometry was examined using linear regression models adjusting for clinical group, age, sex and correlations between members of the same family. RESULTS: The results showed no evidence of association between variation in COMT genotype and lateral ventricular, and left or right hippocampal volumes. Neither was there any effect of the BDNF, 5-HTTLPR, NRG1 and DTNBP1 genotypes on these regional brain volumes. CONCLUSIONS: Abnormal hippocampal and lateral ventricular volumes are among the most replicated endophenotypes for psychosis; however, the influences of COMT, BDNF, 5-HTT, NRG1 and DTNBP1 genes on these key brain regions must be very subtle if at all present.


Asunto(s)
Trastorno Bipolar/genética , Factor Neurotrófico Derivado del Encéfalo/genética , Proteínas Portadoras/genética , Catecol O-Metiltransferasa/genética , Genotipo , Hipocampo/patología , Ventrículos Laterales/patología , Neurregulina-1/genética , Trastornos Psicóticos/genética , Esquizofrenia/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Adolescente , Adulto , Anciano , Trastorno Bipolar/patología , Dominancia Cerebral/genética , Disbindina , Proteínas Asociadas a la Distrofina , Femenino , Estudios de Asociación Genética , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/genética , Fenotipo , Polimorfismo Genético , Polimorfismo de Nucleótido Simple/genética , Trastornos Psicóticos/patología , Valores de Referencia , Esquizofrenia/patología , Adulto Joven
7.
Eur Psychiatry ; 23(7): 527-31, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18774275

RESUMEN

OBJECTIVE: To investigate whether young adults born very preterm (VPT) (<33 weeks) are at increased risk for psychiatric illness in adulthood and whether a family history of psychiatric disorder further increases this risk. METHODS: We assessed 169 VPT and 101 term born individuals using the Clinical Interview Schedule - Revised. RESULTS: Young adults born VPT had an increased risk for psychiatric disorder compared to controls (OR=3.1, 95% CI=1.1-8.6, p=0.03). Those born VPT who had a history of psychiatric disorder in a first-degree relative, had an increase in risk for psychiatric disorder compared to those born VPT without a family history (OR=5.2, 95% CI=1.8-14.9, p=0.002). CONCLUSION: Individuals born VPT are at increased risk of psychiatric illness in young adulthood compared to controls. In addition, a family history of psychiatric disorder in a first-degree relative may leave young adults born VPT particularly vulnerable to psychiatric illness.


Asunto(s)
Trastornos Mentales/epidemiología , Trastornos Mentales/genética , Adolescente , Adulto , Niño , Estudios de Seguimiento , Humanos , Recién Nacido , Recien Nacido Prematuro , Adulto Joven
8.
J Neurol Neurosurg Psychiatry ; 79(4): 381-6, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17682017

RESUMEN

BACKGROUND: Adolescence is a critical period of brain structural reorganisation and maturation of cognitive abilities. This relatively late developmental reorganisation may be altered in individuals who were born preterm. METHODS: We carried out longitudinal neuropsychological testing in 94 very preterm individuals (VPT; before 33 weeks' gestation) and 44 term born individuals at mean ages of 15.3 years (adolescence) and 19.5 years (young adulthood). RESULTS: Full scale, verbal and performance IQ and phonological verbal fluency were significantly lower in the VPT group than the term group at both ages. Repeated measures ANOVA showed only one group by time point interaction for semantic verbal fluency (F = 10.25; df = 107; p = 0.002). Paired-sample t tests showed that semantic verbal fluency increased significantly in the term group over adolescence (t = -5.10; df = 42; p<0.001), but did not increase in the VPT group (t = 0.141; df = 69; p = 0.889). For verbal IQ, there was a significant interaction between time point and sex (F = 4.48; df = 1; p = 0.036) with paired-sample t tests showing that verbal IQ decreased in males between adolescence and adulthood (t = 3.35; df = 71; p = 0.001), but did not change significantly in females (t = 0.20; df = 52; p = 0.845). CONCLUSION: Decrements of intellectual functioning in VPT individuals persist into adulthood. Additionally, there is a deficit in the adolescent maturation of semantic verbal fluency in individuals born VPT.


Asunto(s)
Daño Encefálico Crónico/diagnóstico , Trastornos del Conocimiento/diagnóstico , Enfermedades del Prematuro/diagnóstico , Recién Nacido de muy Bajo Peso , Pruebas Neuropsicológicas , Adolescente , Adulto , Daño Encefálico Crónico/psicología , Niño , Preescolar , Trastornos del Conocimiento/psicología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Enfermedades del Prematuro/psicología , Inteligencia , Trastornos del Desarrollo del Lenguaje/diagnóstico , Trastornos del Desarrollo del Lenguaje/psicología , Masculino , Fonética , Valores de Referencia , Semántica , Medición de la Producción del Habla , Escalas de Wechsler
10.
J Neurol Neurosurg Psychiatry ; 77(4): 495-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16543529

RESUMEN

OBJECTIVE: Individuals born before 33 weeks' gestation (very preterm, VPT) have an increased likelihood of neurological abnormality, impaired cognitive function, and reduced academic performance in childhood. It is currently not known whether neurological signs detected in VPT children persist into adulthood or become attenuated by maturation of the CNS. METHOD: We assessed 153 VPT individuals and 71 term-born controls at 17-18 years old, using a comprehensive neurological examination. This examination divides neurological signs into primary and integrative domains, the former representing the localising signs of classical neurology, and the latter representing signs requiring integration between different neural networks or systems. Integrative signs are sub-divided into three groups: sensory integration, motor confusion, and sequencing. The VPT individuals have been followed up since birth, and neonatal information is available on them, along with the results of neurological assessment at 4 and 8 years of age and neuropsychological assessment at 18 years of age. RESULTS: The total neurology score and primary and integrative scores were significantly increased in VPT young adults compared to term-born controls. Within the integrative domain, sensory integration and motor confusion scores were significantly increased in the VPT group, but sequencing was not significantly different between the VPT and term groups. Integrative neurological abnormalities at 18 were strongly associated with reduced IQ but primary abnormalities were not. CONCLUSIONS: Neurological signs are increased in VPT adults compared to term-born controls, and are strongly associated with reduced neuropsychological function.


Asunto(s)
Encéfalo/anomalías , Encéfalo/fisiopatología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/fisiopatología , Adolescente , Niño , Preescolar , Trastornos del Conocimiento/epidemiología , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Examen Neurológico , Pruebas Neuropsicológicas , Variaciones Dependientes del Observador , Trastornos Psicomotores/diagnóstico , Trastornos Psicomotores/epidemiología , Índice de Severidad de la Enfermedad , Factores Socioeconómicos
11.
Brain ; 124(Pt 1): 60-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11133787

RESUMEN

Individuals born before 33 weeks' gestation are at risk of brain lesions, which have the potential to disrupt subsequent neurodevelopment. As a result they manifest an increased incidence of neuromotor signs and cognitive deficits, which can still be detected in adolescence. The cerebellum is known to be involved in both the co-ordination of movement and in cognitive processes. We therefore set out to establish whether cognitive and motor impairments in adolescents born very pre-term are associated with abnormalities of the cerebellum as revealed by volumetric analysis of brain MRI scans. The volume of the whole cerebellum was determined manually using a PC-based Cavalieri procedure in 67 adolescents born very pre-term and 50 age-matched, full-term born controls. Cognitive and neurological assessments were performed at 1, 4, 8 and 14-15 years of age as part of the long-term follow-up of the pre-term subjects. The pre-term-born subjects had significantly reduced cerebellar volume compared with term-born controls (P<0.001). This difference was still present after controlling for potential confounders. There was no association between cerebellar volume and motor neurological signs. However, there were significant associations between cerebellar volume and several cognitive test scores, in particular the Wechsler Intelligence Scale for Children-Revised, the Kaufman Assessment Battery for Children and the Schonnel reading age. This provides further evidence implicating the cerebellum in cognition and suggests that cerebellar abnormalities may underlie some of the cognitive deficits found in individuals born very pre-term.


Asunto(s)
Cerebelo/crecimiento & desarrollo , Cerebelo/fisiopatología , Trastornos del Conocimiento/diagnóstico , Recien Nacido Prematuro/crecimiento & desarrollo , Trastornos del Movimiento/diagnóstico , Adolescente , Cerebelo/patología , Niño , Preescolar , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/fisiopatología , Comorbilidad , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Trastornos del Movimiento/epidemiología , Trastornos del Movimiento/fisiopatología , Pruebas Psicológicas , Tiempo , Reino Unido/epidemiología
12.
Radiology ; 204(3): 833-8, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9280268

RESUMEN

PURPOSE: To determine the locations and extent of activation in areas of the brain at functional magnetic resonance (MR) imaging with olfactory stimulation and to determine whether accommodation or amplification of brain activation occurs with sequential olfactory stimulation. MATERIALS AND METHODS: Five adult men with normal senses of smell underwent multisection, gradient-echo, echo-planar imaging according to a blood-oxygen-level-dependent experimental paradigm. Odorants that nearly exclusively stimulate the olfactory system and odorants that stimulate the olfactory and trigeminal nerves were compared by using repetitive imaging procedures. RESULTS: Activation with olfactory nerve-mediated odorants was demonstrated in the orbitofrontal cortex (Brodmann area 11) with a right-sided predominance. Mild cerebellar stimulation was also observed. With repeated testing, overall activation with olfactory nerve-mediated odorants declined. Odorants that also stimulated the trigeminal nerve produced additional cingulate, temporal, cerebellar, and occipital activation. Activation with combined trigeminal and olfactory system odors increased more than sixfold with repeated testing. CONCLUSION: Olfactory nerve-mediated and combined olfactory and trigeminal nerve-mediated odorants activate different regions of the brain. Orbitofrontal stimulation spreads to all parts of the brain when a trigeminal component is added. Habituation (deactivation) occurs with repeated testing of olfactory nerve-mediated odorants, while, paradoxically, activation increases with repeated exposure to odors that also stimulate the trigeminal nerve.


Asunto(s)
Encéfalo/anatomía & histología , Encéfalo/fisiología , Imagen por Resonancia Magnética , Odorantes , Estimulación Física , Adulto , Humanos , Masculino , Nervio Olfatorio/fisiología , Nervio Trigémino/fisiología
13.
Magn Reson Imaging ; 15(3): 295-300, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9201676

RESUMEN

Magnetic resonance imaging gives high quality images of the urinary bladder with excellent contrast. We report here the first application of dynamic, multi-slice, echo planar imaging to a study of urinary bladder emptying. Changes in urinary bladder volumes and rates of urine expulsion from the bladder have been measured simultaneously with bladder pressure. The method shows promise for clinical applications involving compromised bladder function, for reappraising bladder contraction strength-volume relationships, and for investigating the rate of change of length, three-dimensional shape, and wall tension in different parts of the bladder during micturition.


Asunto(s)
Imagen Eco-Planar/métodos , Músculo Liso/fisiología , Vejiga Urinaria/anatomía & histología , Micción , Humanos , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Contracción Muscular , Presión , Recto/fisiología , Procesamiento de Señales Asistido por Computador , Método Simple Ciego , Transductores de Presión , Vejiga Urinaria/fisiología , Cateterismo Urinario , Orina , Urodinámica
14.
Magn Reson Imaging ; 13(6): 907-9, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8544664

RESUMEN

Cortical activation in visual association areas known to be responsible for the perception of motion was investigated in two volunteers who viewed a projected animated cartoon periodically "run" and "frozen" during collection of echoplanar MR images. Ten axial, contiguous, 5 mm thick, T2-weighted, gradient-echo images (TE 40 ms, TR 3000 ms) depicting BOLD contrast were acquired through the occipital lobe using a GE Signa 1.5 T system with an advanced NMR operating console. Images were analysed by time series regression modelling estimating power in the MR signal at the ON-OFF frequency of motion. Highly significant activation in response to motion perception was identified in both subjects bilaterally in area V5.


Asunto(s)
Imagen Eco-Planar , Percepción de Movimiento , Corteza Visual/fisiología , Humanos
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