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1.
Hum Brain Mapp ; 34(6): 1399-414, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22359374

RESUMO

BACKGROUND: The attachment model, as assessed by means of the Adult Attachment Interview (AAI), is crucial for understanding emotion regulation and feelings of security in human interactions as well as for the construction of the caregiving system. The caregiving system is a set of representations about affiliative behaviors, guided by sensitivity and empathy, and is fully mature in young-adulthood. Here, we examine how different attachment models influence brain responses in areas related to empathy and emotions in young-adult subjects with secure and dismissing attachment models. METHODS: By means of AAI, we selected 11 nulliparous young-adult females with a secure model and 12 with a dismissing model. Subjects underwent functional magnetic resonance, whereas imitating or observing and empathizing with infant facial expressions. Subjects were tested for alexithymia and reflective functioning. RESULTS: Dismissing subjects activated motor, mirror, and limbic brain areas to a significantly greater extent, but deactivated the medial orbitofrontal cortex (mOFC) and the perigenual anterior cingulated cortex (pACC). During emotional faces, increased activity in dismissing women was seen in the right temporal pole. Furthermore, greater alexithymia was correlated with greater activity in the entorhinal cortex and greater deactivation in the pACC/mOFC. CONCLUSIONS: These findings provide evidence of how the attachment model influences brain responses during a task eliciting attachment. In particular, hyperactivation of limbic and mirror areas may reflect emotional dysregulation of infantile experiences of rejection and lack of protection, whereas increased deactivation of fronto-medial areas may be the expression of the inhibition of attachment behaviors, which is a typical aspect of dismissing attachment.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiologia , Emoções/fisiologia , Empatia/fisiologia , Apego ao Objeto , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Paridade , Adulto Jovem
2.
Mult Scler ; 17(10): 1177-84, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21677022

RESUMO

BACKGROUND: Little is known about the cortical activation changes during clinical relapses in multiple sclerosis (MS). OBJECTIVE: To assess cross-sectional and longitudinal differences in functional magnetic resonance imaging (fMRI) cortical patterns between the relapsing and stable phases of MS. METHODS: We studied 32 patients with relapsing-remitting MS with mild disability: 19 within 48 h of symptom onset of a new relapse (G1) and 13 in the stable phase, relapse-free for at least 6 months (G2). All patients underwent fMRI twice, upon entry (time 1) and 30-50 days later (time 2), during right-hand movement. RESULTS: No between-group differences were observed in age, disability or T2 lesion load. Between-group analysis showed a significant difference in the ipsilateral precentral gyrus (IPG) activation at time 1. Activity differences in the IPG expressed reduced deactivation in G1 compared with G2. Longitudinal changes in brain activity in the IPG were significantly greater in G1 than G2. G1 patients with a slow clinical recovery (n = 8) showed different activity at baseline and greater activity changes over time in the IPG than patients with a fast recovery (n = 11). CONCLUSION: This study shows that the relapsing phase is associated with reduced brain deactivation in the IPG, which is more marked in patients with a slow clinical recovery. Increased cortical excitability associated with inflammation may determine functional modifications within the ipsilateral motor area.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Movimento/fisiologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Adulto , Córtex Cerebral/patologia , Estudos Transversais , Feminino , Mãos/fisiopatologia , Humanos , Interpretação de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/patologia , Adulto Jovem
3.
Brain ; 128(Pt 9): 2146-53, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15901646

RESUMO

Using functional MRI (fMRI), patients with multiple sclerosis showed a greater extent of motor activation than controls. Although functional changes are often interpreted as adaptive and as a contributing factor in limiting the clinical deficit, no longitudinal studies have yet been performed for multiple sclerosis. Sixteen patients with multiple sclerosis, two patients with possible multiple sclerosis and nine age-matched controls underwent two fMRI studies with a time interval of 15-26 months. The motor task consisted of a self-paced sequential finger opposition movement with the right hand. Patients with multiple sclerosis exhibited greater bilateral activation than controls in both fMRI studies. At follow-up, patients showed a reduction in functional activity in the ipsilateral sensorimotor cortex and in the contralateral cerebellum. No significant differences between the two fMRI studies were observed in controls. Activation changes in ipsilateral motor areas correlated inversely with age, extent and progression of T1 lesion load, and occurrence of a new relapse. This study may help the understanding of the evolution of brain plastic changes in multiple sclerosis indicating that, in younger patients with a less structural brain damage and benign clinical course, the brain reorganizes its functional activity towards a more lateralized pattern of brain activation. The tendency towards a normalization of brain functional activity is hampered in older patients and in those developing relapses or new irreversible brain damage.


Assuntos
Atividade Motora , Córtex Motor/fisiopatologia , Esclerose Múltipla/fisiopatologia , Esclerose Múltipla/psicologia , Adulto , Mapeamento Encefálico/métodos , Progressão da Doença , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Desempenho Psicomotor
4.
Psychiatry Res Neuroimaging ; 249: 1-11, 2016 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-27000301

RESUMO

Maternal care during the first year of life provides the foundation for the infant's emotional and cognitive development. Depressive symptoms in mothers can undermine their early dyadic interaction, which may lead to various psychopathological disorders with long-term consequences. During this period, the mother-child interaction is exclusively preverbal and is based on the mother's ability to understand her infant's needs and feelings (i.e., empathy) and on reciprocal imitation of facial expressions that promote a social dialog that influences the development of the infant self. To study the effects of maternal depressive symptoms on neural circuits underlying these processes, we studied 16 healthy mothers (H) and 14 mothers with depressive symptoms (D), as assessed by the Center for Epidemiologic Studies Depression Scale. Subjects underwent functional magnetic resonance during observation/empathizing (OE) and imitation (IM) of the faces of both their own child and of that of an unknown child aged between 6 and 12 months. During OE, D deactivated the orbital and medial prefrontal cortex to a greater extent (compared with H), thus pointing to an increased internally focused cognitive style during rest. Moreover, D, in respect to H, displayed a greater reactivity of the right amygdala, which may be an expression of emotional dysregulation.


Assuntos
Depressão/fisiopatologia , Emoções , Empatia , Expressão Facial , Relações Mãe-Filho/psicologia , Mães/psicologia , Adulto , Tonsila do Cerebelo/fisiopatologia , Desenvolvimento Infantil , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/fisiopatologia
5.
Front Psychol ; 6: 1241, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26379578

RESUMO

The attachment and the caregiving system are complementary systems which are active simultaneously in infant and mother interactions. This ensures the infant survival and optimal social, emotional, and cognitive development. In this brief review we first define the characteristics of these two behavioral systems and the theory that links them, according to what Bowlby called the "attachment-caregiving social bond" (Bowlby, 1969). We then follow with those neuroimaging studies that have focused on this particular issue, i.e., those which have studied the activation of the careging system in women (using infant stimuli) and have explored how the individual attachment model (through the Adult Attachment Interview) modulates its activity. Studies report altered activation in limbic and prefrontal areas and in basal ganglia and hypothalamus/pituitary regions. These altered activations are thought to be the neural substrate of the attachment-caregiving systems interaction.

6.
J Neuroimaging ; 14(4): 380-4, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15358963

RESUMO

The authors describe a case of right fronto-parietal micropoligyria associated with small schizencephaly clefts and the presence of a frontal open-lip schizencephaly with corpus callosum agenesis. A functional magnetic resonance imaging (fMRI) study was performed to evaluate the possible reorganization of cortical functions in a patient presenting a complex malformation pattern and to investigate which cortical areas were activated during left finger movements. An fMRI study was performed during the execution of a repetitive index finger-to-thumb opposition movement with the right hand and the left hand in 2 separate sessions. Movement of the right hand induced a normal motor activation pattern involving the contralateral left sensory-motor cortex. Movement of the left hand produced significant activation of brain cortex. This fMRI study highlights the compensatory role of the ipsilateral cortical pathways in hand movements in the case of a complex brain malformation that involves the main motor activation areas.


Assuntos
Agenesia do Corpo Caloso , Imageamento por Ressonância Magnética/métodos , Córtex Somatossensorial/anormalidades , Meios de Contraste , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade
7.
Magn Reson Imaging ; 20(5): 383-8, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12206862

RESUMO

BACKGROUND AND PURPOSE: The stage at which normal appearing white matter (NAWM) abnormalities first appear in multiple sclerosis (MS) is not clear. The aim of our study was to monitor water diffusion changes over time in NAWM of patients with early MS. METHODS: Out of a consecutive series of patients enrolled in a MR study on clinically isolated syndrome (CIS), we selected 19 subjects who had completed a one year follow-up. The MR scans obtained at baseline and at 12 months were reviewed according to the new criteria on the diagnosis of MS. Lesion load on T2 and T1 weighted images and the trace of the apparent diffusion coefficient in NAWM were measured both at baseline and at 12 months in patients and in 12 healthy controls. RESULTS: In three patients the diagnosis of MS was done at baseline based on MR. Thirteen patients developed MS during the study and in three patients the diagnosis remained "possible MS." TADC in NAWM in patients was significantly higher than in controls at the 12 months' follow-up but not at baseline (controls mean tADC +/- sd = 0.745 +/- 0.02 mm(2)/sec x 10(-3); patients mean tADC(12) +/- sd = 0.767 +/- 0.02 mm(2)/sec x 10(-3); p < 0.02). TADC and T2 lesion load at 12 months were significantly correlated (p < 0.01). Patients exhibiting tADC(12) above a confidence interval had a significantly greater EDSS score at the same time period (EDSS(12) +/- sd = 1.9 +/- 0.5 and = 1.1 +/- 0.4 respectively; p < 0.01). CONCLUSIONS: This study suggests that diffusion MR cannot detect alterations in NAWM of patients with a CIS suggestive of MS. After one year, when most patients develop MS, diffusion MR abnormalities in NAWM become apparent. These abnormalities are correlated with T2 lesion load and may contribute to neurological impairment.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Esclerose Múltipla/patologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Estudos Prospectivos , Estatísticas não Paramétricas
8.
PLoS One ; 8(6): e65315, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23799005

RESUMO

OBJECTIVES: Examination of sensorimotor activation alone in multiple sclerosis (MS) patients may not yield a comprehensive view of cerebral response to task stimulation. Additional information may be obtained by examining the negative BOLD response (deactivation). Aim of this work was to characterize activation and deactivation patterns during passive hand movements in MS patients. METHODS: 13 relapsing remitting-MS patients (RRMS), 18 secondary progressive-MS patients (SPMS) and 15 healthy controls (HC) underwent an fMRI study during passive right-hand movements. Activation and deactivation contrasts in the three groups were entered into ANOVA, age and gender corrected. Post-hoc analysis was performed with one-sample and two-sample t-tests. For each patient we obtained lesion volume (LV) from both T1- and T2-weighted images. RESULTS: Activations showed a progressive extension to the ipsilateral brain hemisphere according to the group and the clinical form (HC

Assuntos
Córtex Motor/fisiopatologia , Esclerose Múltipla Crônica Progressiva/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Retroalimentação Sensorial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Movimento , Estimulação Física
9.
J Alzheimers Dis ; 19(1): 147-59, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20061634

RESUMO

This study investigates abnormalities of grey (GM) and white matter (WM) in Alzheimer's disease (AD), by modeling the AD pathological process as a continuous course between normal aging and fully developed dementia, with amnesic mild cognitive impairment (aMCI) as an intermediate stage. All subjects (9 AD, 16 aMCI patients, and 13 healthy controls) underwent a full neuropsychological assessment and an MRI examination at 3 Tesla, including a volumetric scan and diffusion tensor (DT)-MRI. The volumes were processed to perform a voxel-based morphometric analysis of GM and WM volume, while DT-MRI data were analyzed using tract based spatial statistics, to estimate changes in fractional anisotropy and mean diffusivity data. GM and WM volume and mean diffusivity and fractional anisotropy were compared across the three groups, and their correlation with cognitive functions was investigated. While AD presented a pattern of widespread GM atrophy, tissue loss was more subtle in patients with aMCI. WM atrophy was mainly located in the temporal lobe, but evidence of WM microscopic damage, assessed by DT-MRI, was also observable in the thalamic radiations and in the corpus callosum. Memory and executive functions correlated with either GM volume or fractional anisotropy in fronto-temporal areas. In conclusion, this study shows a comprehensive assessment of the brain tissue damage across AD evolution, providing insights on different pathophysiological mechanisms (GM atrophy, Wallerian degeneration, and brain disconnection) and their possible association with clinical aspects of cognitive decline.


Assuntos
Doença de Alzheimer/patologia , Córtex Cerebral/patologia , Progressão da Doença , Fibras Nervosas Mielinizadas/patologia , Idoso , Doença de Alzheimer/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Hum Brain Mapp ; 28(7): 636-44, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17080438

RESUMO

Functional MRI (fMRI) studies have shown increased activation of ipsilateral motor areas during hand movement in patients with multiple sclerosis (MS). We hypothesized that these changes could be due to disruption of transcallosal inhibitory pathways. We studied 18 patients with relapsing-remitting MS. Conventional T1- and T2-weighted images were acquired and lesion load (LL) measured. Diffusion tensor imaging (DTI) was performed to estimate fractional anisotropy (FA) and mean diffusivity (MD) in the body of the corpus callosum (CC). fMRI was obtained during a right-hand motor task. Patients were studied to evaluate transcallosal inhibition (TCI, latency and duration) and central conduction time (CCT). Eighteen normal subjects were studied with the same techniques. Patients showed increased MD (P < 0.0005) and reduced FA (P < 0.0005) in the body of the CC. Mean latency and duration of TCI were altered in 12 patients and absent in the others. Between-group analysis showed greater activation in patients in bilateral premotor, primary motor (M1), and middle cingulate cortices and in the ipsilateral supplementary motor area, insula, and thalamus. A multivariate analysis between activation patterns, structural MRI, and neurophysiological findings demonstrated positive correlations between T1-LL, MD in the body of CC, and activation of the ipsilateral motor cortex (iM1) in patients. Duration of TCI was negatively correlated with activation in the iM1. Our data suggest that functional changes in iM1 in patients with MS during a motor task partially represents a consequence of loss of transcallosal inhibitory fibers.


Assuntos
Corpo Caloso/patologia , Lateralidade Funcional/fisiologia , Córtex Motor/fisiopatologia , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Desempenho Psicomotor/fisiologia , Adulto , Mapeamento Encefálico , Corpo Caloso/irrigação sanguínea , Imagem de Difusão por Ressonância Magnética , Avaliação da Deficiência , Estimulação Elétrica , Potencial Evocado Motor , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Córtex Motor/irrigação sanguínea , Oxigênio/sangue , Tempo de Reação/fisiologia , Análise de Regressão , Estimulação Magnética Transcraniana
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