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1.
IEEE Trans Haptics ; 13(1): 45-51, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32092013

RESUMO

Ultrasound transducer arrays are capable of producing tactile sensations on the hand, promising hands-free haptic interaction for virtual environments. However, controlling such an array with respect to reproducing a desired perceived interaction remains a challenging problem. In this article, we approach this problem as a dynamic mapping of virtual interactions to existing control metaphors of ultrasound devices, namely, the modulation of focal point positions and intensities over time, a method known as Spatiotemporal Modulation (STM). In particular, we propose an optimization approach that takes into account known perceptual parameters and limitations of the STM method. This results in a set of focal point paths optimized to best reconstruct an arbitrary target pressure field.

2.
Psychiatry Res ; 286: 112822, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32086029

RESUMO

The DSM-5 Level 1 Cross-Cutting Symptom Measure-Adult (DSM XC) was developed by the American Psychiatric Association (APA) as a transdiagnostic measure of current mental health symptomatology. This paper describes utilization of the DSM XC to screen volunteers for participation in mental health research studies as healthy controls. Research volunteers completed an online, modified version of the DSM XC, which along with other clinical information, was used to determine eligibility for participation as a healthy control. The sensitivity and specificity of screening positive on the DSM XC for this eligibility decision were calculated. Of 506 volunteers who completed the screening process, 159 (31%) were ineligible due to mental health reasons. The DSM XC sensitivity in predicting this determination was 64.2% [95% CI: 56.5 - 71.3] and its specificity was 83.9% [95% CI: 79.7 - 87.5]. When DSM XC responses were combined with information about current psychotropic medication use, an important determinant of study eligibility, the sensitivity improved to 81.8% [95% CI: 75.3 - 87.2). These findings provide preliminary support for the use of the DSM XC as an initial screening tool for mental health studies that enroll healthy research volunteers, particularly when supplemented by additional clinical history such as psychotropic medication use.

3.
Ann Plast Surg ; 83(6): 618-621, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31688106

RESUMO

AIM: Over the new year period, we recognized a high number of admissions with postoperative complications following cosmetic surgery abroad. We aimed to determine the driving forces behind this and financial impact on the National Health Service (NHS). METHODS: Cases of all patients attending the regional plastic surgery unit with complications following surgery abroad were reviewed. Patients completed a survey on the perioperative period abroad and driving forces. In addition, the costing department was contacted to determine the financial burden associated with cosmetic tourism. RESULTS: Six patients were admitted to the regional unit after independently organizing surgery abroad. Countries visited included Turkey, Belgium, Poland, Estonia, and India. Reasons included cost and access to procedures not recommended by UK surgeon. Type of surgery included breast (5), abdominoplasty (2), liposuction (2), and labiaplasty (1), and 50% had multiple procedures. Complications included necrotic wounds (33%), infected breast implant (33%), venous thromboembolism investigated (33%), and wound infection (17%). Overall, 67% required surgery on the NHS. The total cost was £23,976.82, with an average of £4000/patient (range, £1294-£6291). DISCUSSION/CONCLUSIONS: This surge in cosmetic complications occurred in the New Year period. Complications were seen after a wide range of surgical procedures. All patients required an inpatient stay, and two-thirds required surgery with a significant cost burden to the NHS. Patients are unaware of the risks involved, highlighted by the lack of preoperative counseling and follow-up. In addition, this series has highlighted the risks associated with traveling in the perioperative period, with 2 patients investigated for pulmonary embolus.

4.
Clin Psychopharmacol Neurosci ; 16(4): 449-460, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30466217

RESUMO

Objective: Prior functional magnetic resonance imaging (fMRI) work has revealed that children/adolescents with disruptive behavior disorders (DBDs) show dysfunctional reward/non-reward processing of non-social reinforcements in the context of instrumental learning tasks. Neural responsiveness to social reinforcements during instrumental learning, despite the importance of this for socialization, has not yet been previously investigated. Methods: Twenty-nine healthy children/adolescents and 19 children/adolescents with DBDs performed the fMRI social/non-social reinforcement learning task. Participants responded to random fractal image stimuli and received social and non-social rewards/non-rewards according to their accuracy. Results: Children/adolescents with DBDs showed significantly reduced responses within the caudate and posterior cingulate cortex (PCC) to non-social (financial) rewards and social non-rewards (the distress of others). Connectivity analyses revealed that children/adolescents with DBDs have decreased positive functional connectivity between the ventral striatum (VST) and the ventromedial prefrontal cortex (vmPFC) seeds and the lateral frontal cortex in response to reward relative to non-reward, irrespective of its sociality. In addition, they showed decreased positive connectivity between the vmPFC seed and the amygdala in response to non-reward relative to reward. Conclusion: These data indicate compromised reinforcement processing of both non-social rewards and social non-rewards in children/adolescents with DBDs within core regions for instrumental learning and reinforcement-based decision- making (caudate and PCC). In addition, children/adolescents with DBDs show dysfunctional interactions between the VST, vmPFC, and lateral frontal cortex in response to rewarded instrumental actions potentially reflecting disruptions in attention to rewarded stimuli.

5.
Neurology ; 91(20): e1870-e1879, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-30305450

RESUMO

OBJECTIVE: To explore alterations in gray matter volume in patients with functional movement disorders. METHODS: We obtained T1-weighted MRI on 48 patients with clinically definite functional movement disorders, a subset of functional neurologic symptom disorder characterized by abnormal involuntary movements, and on 55 age- and sex-matched healthy controls. We compared between-group differences in gray matter volume using voxel-based morphometry across the whole brain. All participants in addition underwent a thorough neuropsychological battery, including the Hamilton Anxiety and Depression Scales and the Childhood Trauma Questionnaire. To determine whether confounding factors such as comorbid depression, anxiety, or childhood trauma exposure contributed to the observed structural changes, nonparametric correlation analysis was performed. RESULTS: Patients with functional movement disorders exhibited increased volume of the left amygdala, left striatum, left cerebellum, left fusiform gyrus, and bilateral thalamus, and decreased volume of the left sensorimotor cortex (whole-brain corrected p ≤ 0.05). Volumetric differences did not correlate with measures of disease duration or patient-rated disease severity. CONCLUSION: This study demonstrates that patients with functional movement disorders exhibit structural gray matter abnormalities in critical components of the limbic and sensorimotor circuitry. These abnormalities may represent a premorbid trait rendering patients more susceptible to disease, the disease itself, or a compensatory response to disease.


Assuntos
Encéfalo/patologia , Substância Cinzenta/patologia , Transtornos dos Movimentos/patologia , Adulto , Idoso , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
PLoS One ; 13(8): e0202097, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30138455

RESUMO

PURPOSE: To determine the incidence of new choroidal neovascularization (CNV) in eyes with dry age-related macular degeneration (AMD) following subthreshold diode micropulse laser (SDM). METHOD: In an observational retrospective cohort study, the records of all patients active in the electronic medical records database were reviewed to identify eyes with dry AMD treated with SDM. Identified eyes were classified by simplified AREDS categories, and analyzed for the primary endpoint of new CNV after treatment. RESULTS: The EMR revealed SDM was offered to 373/392 (95%) patients with dry AMD and elected by 363/373 (97%) between 2008-2017. Follow up was available for 354/363 patients (547 eyes, 98%) (range 6-108 mos., avg. 22). CNV risk factors included age (median 84 years, 67% > 80); reticular pseudodrusen (214 eyes, 39%); AREDS category (78% category 3 and 4); and fellow eye CNV (128 eyes, 23%). New CNV developed in 9/547 eyes (1.6%, annualized rate 0.87%). Visual acuity was unchanged. There were no adverse treatment effects. SUMMARY: In a review of a large group of eyes with exceptionally high-risk AMD, SDM was followed by a very low incidence of new CNV. If confirmed by further study, SDM would offer a new and highly effective treatment to reduce the risk of vision loss from AMD.


Assuntos
Neovascularização de Coroide/epidemiologia , Neovascularização de Coroide/etiologia , Terapia a Laser/efeitos adversos , Degeneração Macular/complicações , Degeneração Macular/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Seguimentos , Humanos , Incidência , Estimativa de Kaplan-Meier , Terapia a Laser/métodos , Degeneração Macular/terapia , Masculino , Medição de Risco , Fatores de Risco
7.
Compend Contin Educ Dent ; 39(5): 318-324, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29714498

RESUMO

OBJECTIVE: To evaluate the reliability, ease, and efficiency of data entry for an oral health screening app that allows iPad® entry of data, including permanent versus deciduous teeth present, visual image comparison grading of demineralization/caries, fluorosis, periodontal inflammation, oral hygiene status, identification of sealants/restorations, dental trauma, orthodontic malocclusion, mandibular joint dysfunction, and early childhood caries. METHODS: 89 consented children were examined first by a public health dental hygienist in a dental office reception area and then by a dentist in a treatment operatory. The same research associate was used to prompt and record both examinations. RESULTS: The screenings prompted by the electronic oral health screening system were completed in 2 to 3 minutes each with favorable levels of comparison between examiners as assessed by weighted Kappa scores measuring 0.531 for all teeth examined, with the lower back teeth showing the greatest agreement (K = 0.601) and the upper back and upper front demonstrating less agreement (K = 0.446 and 0.468, respectively). Neither examiner identified any carious lesions among the lower front teeth. CONCLUSIONS: This study provides the first description of an oral health screening entry app with visual image comparisons and touchscreen data entry for efficient collection of oral health information.


Assuntos
Registros Odontológicos , Diagnóstico Bucal , Programas de Rastreamento/métodos , Saúde Bucal , Software , Criança , Humanos
8.
J Abnorm Child Psychol ; 46(4): 741-754, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28776147

RESUMO

Theoretical models have implicated amygdala dysfunction in the development of Disruptive Behavior Disorders (DBDs; Conduct Disorder/Oppositional Defiant Disorder). Amygdala dysfunction impacts valence evaluation/response selection and emotion attention in youth with DBDs, particularly in those with elevated callous-unemotional (CU) traits. However, amygdala responsiveness during social cognition and the responsiveness of the acute threat circuitry (amygdala/periaqueductal gray) in youth with DBDs have been less well-examined, particularly with reference to CU traits. 31 youth with DBDs and 27 typically developing youth (IQ, age and gender-matched) completed a threat paradigm during fMRI where animate and inanimate, threatening and neutral stimuli appeared to loom towards or recede from participants. Reduced responsiveness to threat variables, including visual threats and encroaching stimuli, was observed within acute threat circuitry and temporal, lateral frontal and parietal cortices in youth with DBDs. This reduced responsiveness, at least with respect to the looming variable, was modulated by CU traits. Reduced responsiveness to animacy information was also observed within temporal, lateral frontal and parietal cortices, but not within amygdala. Reduced responsiveness to animacy information as a function of CU traits was observed in PCC, though not within the amygdala. Reduced threat responsiveness may contribute to risk taking and impulsivity in youth with DBDs, particularly those with high levels of CU traits. Future work will need to examine the degree to which this reduced response to animacy is independent of amygdala dysfunction in youth with DBDs and what role PCC might play in the dysfunctional social cognition observed in youth with high levels of CU traits.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico por imagem , Transtorno da Conduta/diagnóstico por imagem , Adolescente , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Criança , Transtorno da Conduta/psicologia , Emoções/fisiologia , Humanos , Imagem por Ressonância Magnética , Masculino
9.
Clin Psychopharmacol Neurosci ; 15(4): 369-381, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-29073749

RESUMO

Objective: In the current study we investigated neurodevelopmental changes in response to social and non-social reinforcement. Methods: Fifty-three healthy participants including 16 early adolescents (age, 10-15 years), 16 late adolescents (age, 15-18 years), and 21 young adults (age, 21-25 years) completed a social/non-social reward learning task while undergoing functional magnetic resonance imaging. Participants responded to fractal image stimuli and received social or non-social reward/non-rewards according to their accuracy. ANOVAs were conducted on both the blood oxygen level dependent response data and the product of a context-dependent psychophysiological interaction (gPPI) analysis involving ventromedial prefrontal cortex (vmPFC) and bilateral insula cortices as seed regions. Results: Early adolescents showed significantly increased activation in the amygdala and anterior insula cortex in response to non-social monetary rewards relative to both social reward/non-reward and monetary non-rewards compared to late adolescents and young adults. In addition, early adolescents showed significantly more positive connectivity between the vmPFC/bilateral insula cortices seeds and other regions implicated in reinforcement processing (the amygdala, posterior cingulate cortex, insula cortex, and lentiform nucleus) in response to non-reward and especially social non-reward, compared to late adolescents and young adults. Conclusion: It appears that early adolescence may be marked by: (i) a selective increase in responsiveness to non-social, relative to social, rewards; and (ii) enhanced, integrated functioning of reinforcement circuitry for non-reward, and in particular, with respect to posterior cingulate and insula cortices, for social non-reward.

10.
Neuroimage Clin ; 16: 498-506, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28971003

RESUMO

Atypical amygdala responses to emotional stimuli have been consistently reported in youth with Disruptive Behavior Disorders (DBDs; Conduct Disorder/Oppositional Defiant Disorder). However, responding to animacy stimuli has not been systematically investigated. Yet, the amygdala is known to be responsive to animacy stimuli and impairment in responsiveness to animacy information may have implications for social cognitive development. Twenty-nine youth with DBDs and 20 typically developing youth, matched for IQ, age (Mage  = 14.45, SD = 2.05) and gender, completed a dot probe task during fMRI. Stimuli consisted of negative/faces, negative/objects, neutral/faces and neutral/objects images. Youth with DBDs, relative to typically developing youth, showed: i) reduced amygdala and lateral temporal cortex responses to faces relative to objects. Moreover, within the group of youth with DBDs, increasing callous-unemotional traits were associated with lesser amygdala responses to faces relative to objects. These data suggest that youth with DBDs, particularly those with high levels of CU traits exhibit dysfunction in animacy processing in the amygdala. This dysfunction may underpin the asociality reported in these youth.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Emoções/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino
11.
IEEE Trans Haptics ; 10(4): 580-600, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28500008

RESUMO

In the last decade, we have witnessed a drastic change in the form factor of audio and vision technologies, from heavy and grounded machines to lightweight devices that naturally fit our bodies. However, only recently, haptic systems have started to be designed with wearability in mind. The wearability of haptic systems enables novel forms of communication, cooperation, and integration between humans and machines. Wearable haptic interfaces are capable of communicating with the human wearers during their interaction with the environment they share, in a natural and yet private way. This paper presents a taxonomy and review of wearable haptic systems for the fingertip and the hand, focusing on those systems directly addressing wearability challenges. The paper also discusses the main technological and design challenges for the development of wearable haptic interfaces, and it reports on the future perspectives of the field. Finally, the paper includes two tables summarizing the characteristics and features of the most representative wearable haptic systems for the fingertip and the hand.


Assuntos
Mãos , Estimulação Física/instrumentação , Tato , Dispositivos Eletrônicos Vestíveis , Retroalimentação , Humanos , Dispositivos Eletrônicos Vestíveis/classificação
12.
Psychosomatics ; 57(6): 566-575, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27377316

RESUMO

BACKGROUND: Patients with functional movement disorders (FMDs) are commonly seen by neurologists and psychosomatic medicine psychiatrists. Research literature provides scant information about the subjective experiences of individuals with this often chronic problem. OBJECTIVE: To enhance our understanding of psychologic aspects of FMDs by conducting qualitative interviews of research subjects. METHODS: In total, 36 patients with FMDs were recruited from the Human Motor Control clinic at the National Institutes of Health. Each subject participated in a qualitative psychiatric interview and a structured diagnostic psychiatric interview. RESULTS: Of our 36 subjects, 28 had current or lifetime psychiatric disorders in addition to conversion disorder and 22 had current disorders. Qualitative interviews provided rich information on patients' understanding of their illnesses and impaired cognitive processing of emotions. CONCLUSION: Our study supports the addition of open-ended qualitative interviews to delineate emotional dynamics and conceptual frameworks among such patients. Exploratory interviews generate enhanced understanding of such complex patients, above and beyond that gained by assessing DSM diagnostic comorbidities.


Assuntos
Entrevista Psicológica/métodos , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Transtornos dos Movimentos/psicologia , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Transtornos dos Movimentos/complicações
13.
Am J Psychiatry ; 173(3): 282-90, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26441155

RESUMO

OBJECTIVE: Youths with disruptive behavior disorders (DBD) (conduct disorder and oppositional defiant disorder) have an elevated risk for maladaptive reactive aggression. Theory suggests that this is due to an elevated sensitivity of basic threat circuitry implicated in retaliation (amygdala/periaqueductal gray) in youths with DBD and low levels of callous-unemotional traits and dysfunctional regulatory activity in the ventromedial prefrontal cortex in youths with DBD irrespective of callous-unemotional traits. METHOD: A total of 56 youths 10-18 years of age (23 of them female) participated in the study: 30 youths with DBD, divided by median split into groups with high and low levels of callous-unemotional traits, and 26 healthy youths. All participants completed an ultimatum game task during functional MRI. RESULTS: Relative to the other groups, youths with DBD and low levels of callous-unemotional traits showed greater increases in activation of basic threat circuitry when punishing others and dysfunctional down-regulation of the ventromedial prefrontal cortex during retaliation. Relative to healthy youths, all youths with DBD showed reduced amygdala-ventromedial prefrontal cortex connectivity during high provocation. Ventromedial prefrontal cortex responsiveness and ventromedial prefrontal cortex-amygdala connectivity were related to patients' retaliatory propensity (behavioral responses during the task) and parent-reported reactive aggression. CONCLUSIONS: These data suggest differences in the underlying neurobiology of maladaptive reactive aggression in youths with DBD who have relatively low levels of callous-unemotional traits. Youths with DBD and low callous-unemotional traits alone showed significantly greater threat responses during retaliation relative to comparison subjects. These data also suggest that ventromedial prefrontal cortex-amygdala connectivity is critical for regulating retaliation/reactive aggression and, when dysfunctional, contributes to reactive aggression, independent of level of callous-unemotional traits.


Assuntos
Agressão/fisiologia , Tonsila do Cerebelo/fisiopatologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo , Comportamento Infantil/fisiologia , Emoções/fisiologia , Córtex Pré-Frontal/fisiopatologia , Adolescente , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/terapia , Criança , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Comportamento Problema , Escalas de Graduação Psiquiátrica , Análise e Desempenho de Tarefas
14.
Neuroimage Clin ; 9: 545-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26640766

RESUMO

BACKGROUND: There are suggestions that patients with attention-deficit/hyperactivity disorder (ADHD) show impairment in executive attention control and emotion regulation. This study investigated emotion regulation as a function of the recruitment of executive attention in patients with ADHD. METHODS: Thirty-five healthy children/adolescents (mean age = 13.91) and twenty-six children/adolescents with ADHD (mean age = 14.53) participated in this fMRI study. They completed the affective Stroop paradigm viewing positive, neutral and negative images under varying cognitive loads. A 3-way ANOVA (diagnosis-by-condition-by-emotion) was conducted on the BOLD response data. Following this, 2 3-way ANOVAs (diagnosis-by-condition-by-emotion) were applied to context-dependent psychophysiological interaction (gPPI) analyses generated from a dorsomedial frontal cortex and an amygdala seed (identified from the BOLD response ANOVA main effects of condition and emotion respectively). RESULTS: A diagnosis-by-condition interaction within dorsomedial frontal cortex revealed reduced recruitment of dorsomedial frontal cortex as a function of increased task demands in the children/adolescents with ADHD relative to healthy children/adolescents. The level of reduction in recruitment of dorsomedial frontal cortex was significantly correlated with symptom severity (total and hyperactivity) measured by Conner's Parent Report Scale in the children/adolescents with ADHD. In addition, analysis of gPPI data from a dorsomedial frontal cortex seed revealed significant diagnosis-by-condition interactions within lateral frontal cortex; connectivity between dorsomedial frontal cortex and lateral frontal cortex was reduced in the patients with ADHD relative to comparison youth during congruent and incongruent task trials relative to view trials. There were no interactions of group, or main effect of group, within the amygdala in the BOLD response ANOVA (though children/adolescents with ADHD showed increased responses to positive images within temporal cortical regions during task trials; identified by the diagnosis-by-condition-by-emotion interaction). However, analysis of gPPI data from an amygdala seed revealed decreased connectivity between amygdala and lentiform nucleus in the presence of emotional stimuli in children/adolescents with ADHD (diagnosis-by-emotion interaction). CONCLUSION: The current study demonstrated disrupted recruitment of regions implicated in executive function and impaired connectivity within those regions in children/adolescents with ADHD. There were also indications of heightened representation of emotional stimuli in patients with ADHD. However, as the findings were specific for positive stimuli, the suggestion of a general failure in emotion regulation in ADHD was not supported.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Encéfalo/irrigação sanguínea , Transtornos Cognitivos/etiologia , Função Executiva/fisiologia , Transtornos do Humor/etiologia , Adolescente , Análise de Variância , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Escalas de Graduação Psiquiátrica , Tempo de Reação/fisiologia
15.
IEEE Trans Haptics ; 7(4): 533-44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25122594

RESUMO

With real-time models of friction that take velocity as input, accuracy depends in great part on adequately estimating velocity from position measurements. This process can be sensitive to noise, especially at high sampling rates. In audio-haptic acoustic simulations, often characterized by friction-induced, relaxation-type stick-slip oscillations, this gives a gritty, dry haptic feel and a raspy, unnatural sound. Numerous techniques have been proposed, but each depend on tuning parameters so that they may offer a good trade-off between delay and noise rejection. In an effort to compare fairly, each of thirteen methods considered in the present study was automatically optimized and evaluated; finally a subset of these were compared subjectively. Results suggest that no one method is ideal for all gain levels, though the best general performance was found by using a sliding-mode differentiator as input to a Kalman integrator. An additional conclusion is that estimators do not approach the quality available in physical velocity transduction, and therefore such sensors should be considered in haptic device design.


Assuntos
Algoritmos , Simulação por Computador , Ergonomia/métodos , Fricção , Modelos Teóricos , Som , Acústica , Desenho de Equipamento
16.
Neuropsychologia ; 62: 277-85, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25128588

RESUMO

In this study, we aimed to investigate age related changes in systems implicated in top down attention and the implications of this for amygdala responses to emotional distracters. Fifty-one healthy subjects including 18 children (aged 10-14), 15 adolescents (aged 14-18), and 18 young adults (aged 18-25) completed the affective Stroop paradigm while undergoing functional MRI. While achieving comparable behavioral performance, children, relative to adolescents and adults, showed increased activation in areas including anterior cingulate gyrus and precentral gyrus in task relative to view trials. In addition, children showed increased activation within the amygdala and fusiform gyrus in response to emotional stimuli. Notably, the group difference within the amygdala was particularly pronounced during task trials. Also children showed increased connectivity between amygdala and superior frontal gyrus and bilateral postcentral gyrii in response to negative task trials. These data are consistent with previous work indicating less consolidated functional integrity in regions implicated in top down attention in children relative to older participants and extend this work by indicating that this less consolidated functional integrity leads to reduced automatic emotion regulation as a function of top down attention. Given that reduced automatic emotion regulation as a function of top down attention is considered a risk factor for the development of anxiety disorders, these data may contribute to an understanding of the increased risk for the development of these disorders at this age.


Assuntos
Atenção/fisiologia , Encéfalo/crescimento & desenvolvimento , Desenvolvimento Infantil/fisiologia , Emoções/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Adolescente , Adulto , Análise de Variância , Encéfalo/irrigação sanguínea , Mapeamento Encefálico , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Masculino , Vias Neurais/irrigação sanguínea , Vias Neurais/crescimento & desenvolvimento , Oxigênio/sangue , Teste de Stroop , Adulto Jovem
17.
Retina ; 34(10): 2010-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24837050

RESUMO

PURPOSE: To determine the safety of transfoveal subthreshold diode micropulse laser for fovea-involving diabetic macular edema. METHODS: The records of all patients treated with transfoveal subthreshold diode micropulse laser for fovea-involving diabetic macular edema in two retina clinics were reviewed. The eligibility included fovea-involving diabetic macular edema by spectral domain optical coherence tomography and pretreatment visual acuity of 20/40 or better. RESULTS: Thirty-nine eyes of 27 patients aged 50 years to 87 years (mean, 69 years) were included. Postoperative follow-up ranged from 3 months to 36 months (mean, 11 months). Fourteen patients were insulin dependent, and 19 had nonproliferative retinopathy. The preoperative visual acuity was 20/20 (10 eyes), 20/25 (10 eyes), 20/30 (8 eyes), and 20/40 (11 eyes). No eye had evidence of laser-induced macular damage by any imaging means postoperatively. There were no adverse treatment effects. Logarithm of the minimum angle of resolution visual acuity was improved on average of 0.03 units at 4 months to 7 months of follow-up (P = 0.0449, paired t-test) and otherwise stable. The central foveal thickness was improved at 4 months to 7 months (P = 0.05, paired t-test) and 8 months to 12 months, postoperatively (P = 0.04, mixed model accounting). Maximum macular thickness was improved at 4 months to 7 months postoperatively (P = 0.01, paired t-test and mixed model accounting). CONCLUSION: In a small retrospective series, transfoveal subthreshold diode micropulse laser was safe and effective for the treatment of fovea-involving diabetic macular edema in eyes with good preoperative visual acuity that were not the candidates for conventional photocoagulation or intravitreal injection. Further study is warranted.


Assuntos
Retinopatia Diabética/radioterapia , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade , Edema Macular/radioterapia , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/fisiopatologia , Feminino , Seguimentos , Fóvea Central , Humanos , Edema Macular/diagnóstico , Edema Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Limiar Sensorial , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
18.
J Am Acad Child Adolesc Psychiatry ; 53(5): 579-88.e9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24745957

RESUMO

OBJECTIVE: Youth with disruptive behavior disorders (DBD), including conduct disorder (CD) and oppositional defiant disorder (ODD), have difficulties in reinforcement-based decision making, the neural basis of which is poorly understood. Studies examining decision making in youth with DBD have revealed reduced reward responses within the ventromedial prefrontal cortex/orbitofrontal cortex (vmPFC/OFC), increased responses to unexpected punishment within the vmPFC and striatum, and reduced use of expected value information in the anterior insula cortex and dorsal anterior cingulate cortex during the avoidance of suboptimal choices. Previous work has used only monetary reinforcement. The current study examined whether dysfunction in youth with DBD during decision making extended to environmental reinforcers. METHOD: A total of 30 youth (15 healthy youth and 15 youth with DBD) completed a novel reinforcement-learning paradigm using environmental reinforcers (physical threat images, e.g., striking snake image; contamination threat images, e.g., rotting food; appetitive images, e.g., puppies) while undergoing functional magnetic resonance imaging (fMRI). RESULTS: Behaviorally, healthy youth were significantly more likely to avoid physical threat, but not contamination threat, stimuli than youth with DBD. Imaging results revealed that youth with DBD showed significantly reduced use of expected value information in the bilateral caudate, thalamus, and posterior cingulate cortex during the avoidance of suboptimal responses. CONCLUSIONS: The current data suggest that youth with DBD show deficits to environmental reinforcers similar to the deficits seen to monetary reinforcers. Importantly, this deficit was unrelated to callous-unemotional (CU) traits, suggesting that caudate impairment may be a common deficit across youth with DBD.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo/fisiopatologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Transtorno da Conduta/fisiopatologia , Transtorno da Conduta/psicologia , Imagem por Ressonância Magnética , Meio Social , Adolescente , Nível de Alerta/fisiologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/diagnóstico , Encéfalo/fisiopatologia , Núcleo Caudado/fisiopatologia , Criança , Transtorno da Conduta/diagnóstico , Tomada de Decisões/fisiologia , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Rede Nervosa/fisiopatologia
19.
J Am Acad Child Adolesc Psychiatry ; 53(4): 456-65.e1, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24655655

RESUMO

OBJECTIVE: Although there is growing evidence of brain abnormalities among individuals with conduct disorder (CD), the structural neuroimaging literature is mixed and frequently aggregates cortical volume rather than differentiating cortical thickness from surface area. The current study assesses CD-related differences in cortical thickness, surface area, and gyrification as well as volume differences in subcortical structures critical to neurodevelopmental models of CD (amygdala; striatum) in a carefully characterized sample. We also examined whether group structural differences were related to severity of callous-unemotional (CU) traits in the CD sample. METHOD: Participants were 49 community adolescents aged 10 to 18 years, 22 with CD and 27 healthy comparison youth. Structural MRI was collected and the FreeSurfer image analysis suite was used to provide measures of cortical thickness, surface area, and local gyrification as well as subcortical (amygdala and striatum) volumes. RESULTS: Youths with CD showed reduced cortical thickness in the superior temporal cortex. There were also indications of reduced gyrification in the ventromedial frontal cortex, particularly for youths with CD without comorbid attention-deficit/hyperactivity disorder. There were no group differences in cortical surface area. However, youths with CD also showed reduced amygdala and striatum (putamen and pallidum) volumes. Right temporal cortical thickness was significantly inversely related to severity of CU traits. CONCLUSIONS: Youths with CD show reduced cortical thickness within superior temporal regions, some indication of reduced gyrification within ventromedial frontal cortex and reduced amygdala and striatum (putamen and pallidum) volumes. These results are discussed with reference to neurobiological models of CD.


Assuntos
Tonsila do Cerebelo/patologia , Transtorno da Personalidade Antissocial/patologia , Transtorno da Conduta/patologia , Globo Pálido/patologia , Córtex Pré-Frontal/patologia , Putamen/patologia , Lobo Temporal/patologia , Adolescente , Criança , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino
20.
Hum Brain Mapp ; 35(5): 2137-47, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23868733

RESUMO

OBJECTIVES: The neural correlates of human cooperative behavior remain poorly understood. Previous work has suggested that increases in striatal activation while punishing unfair offers represents reward signaling. However, other regions are also implicated when punishing others, for example dorsomedial frontal cortex (dmFC), anterior insula cortex (AIC), and periaqueductal gray (PAG). Moreover, the response of other regions implicated in signaling reward, for example ventromedial prefrontal cortex (vmPFC) or posterior cingulate cortex (PCC), has not been systematically examined. EXPERIMENTAL DESIGN: Functional magnetic resonance imaging utilizing parametric modulation was conducted on 21 healthy adults participating in a social exchange paradigm. PRINCIPAL OBSERVATIONS: Participants showed significant positive modulation of activity as a function of delivered punishment in caudate, dmFC, AIC, and PAG; that is, higher punishments by participants of unsatisfactory offers were associated with increasing activity within these regions. However, participants showed significant negative modulation of activity as a function of delivered punishment in vmPFC and PCC; increases in punishment level by participants were associated with decreases in activity within these regions. CONCLUSIONS: The current data question whether caudate activity when punishing unfair offers should be considered to indicate the reward value of this punishment. Instead, this activity, in conjunction with activity within dmFC, AIC, and PAG, may represent the organization of an untypical, punishing response that represents a reactive aggressive response to provocation. Notably, an inverse, regulatory relationship between vmPFC and PAG activity has been previously implicated in the context of another stimulus for reactive aggression; looming threat (Mobbs et al. [2007]: Science 317:1079-1083).


Assuntos
Agressão/fisiologia , Encéfalo/fisiologia , Princípios Morais , Punição , Recompensa , Adulto , Encéfalo/irrigação sanguínea , Feminino , Jogos Experimentais , Humanos , Processamento de Imagem Assistida por Computador , Modelos Lineares , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Adulto Jovem
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