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1.
Gesundheitswesen ; 85(10): 926-936, 2023 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-37793410

RESUMO

OBJECTIVE: The aim of this study was to give an overview of the content, procedure and diagnostic methods used for the school entrance examination (SEE) in Germany. The focus was on the general implementation of the SEE and the developmental screening methods in the individual federal states of Germany. METHOD: A total of 183 employees from the public health authorities from 15 different states took part in an online survey. RESULTS: The results showed a very heterogeneous picture with regard to the SEE, with the information provided by the employees varying both between and within most states. However, most frequently the SEE was carried out by physicians from the public health service within one examination (single stage), took 46 to 60 minutes per child, and administered not earlier than 12 months before school entrance. In terms of content, the focus was on the physical and cognitive development of the children. Most employees of the health authorities reported that they had specific requirements from the state or municipality for the implementation of the SEE. The Social Pediatric Screening of Developmental Status for School Entry (SOPESS) was the screening instrument used most often. In addition, it was reported that the majority of screenings lasted between 16 to 30 minutes, were executed completely and carried out in the same order. In around 50-60% of the cases, it was assumed that the screenings used met the scientific quality criteria. CONCLUSIONS: The present study offers an opportunity to compare the different approaches to the implementation of the SEE and to suggest further developments.


Assuntos
Programas de Rastreamento , Saúde Pública , Humanos , Criança , Alemanha , Instituições Acadêmicas , Exame Físico
2.
Gesundheitswesen ; 85(10): 937-944, 2023 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-37527688

RESUMO

The School Entrance Examination (SEE) provides important information about the educational needs of pre-school children and for health reporting. The SEE should reflect the latest scientific knowledge and generate high-quality data. To do this, it must meet scientific quality criteria and be continuously evaluated and further developed. Regarding the high relevance of the data and the enormous resources needed to test all pre-school children, the SEE must face a scientific and public debate with regard to its usefulness, content and structure. This requires a transparent communication and publication practice. The aim of this overview article was to summarize the publicly available information on the developmental screening incorporated in the SEE in the different federal states of Germany and to evaluate it in terms of transparency, completeness and scientific quality. While the assessed abilities were very similar, there were major differences in the timing of the SEE, whether a one- or multi-stage procedure was used and the extent to which all children were examined by physicians from the public health service. SOPESS is the most frequently used developmental screening method in Germany, for which sufficient quality criteria have been identified. For some of the other widely used methods, validation and standardization were found to be lacking. Overall, there is little publicly available information or scientific publications on the SEE. The heterogeneity of the procedures used in Germany can be seen as an opportunity for the further development and improvement of the SEE. Continuous communication between public health authorities and users as well as thorough scientific monitoring and public debate would be desirable in this context.

3.
Psychol Res ; 86(1): 125-140, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33595706

RESUMO

Stimuli that predict a rewarding outcome can cause difficulties to inhibit unfavourable behaviour. Research suggests that this is also the case for stimuli with a history of reward extending these effects on action control to situations, where reward is no longer accessible. We expand this line of research by investigating if previously reward-predictive stimuli promote behavioural activation and impair motor inhibition in a second unrelated task. In two experiments participants were trained to associate colours with a monetary reward or neutral feedback. Afterwards participants performed a cued go/no-go task, where cues appeared in the colours previously associated with feedback during training. In both experiments training resulted in faster responses in rewarded trials providing evidence of a value-driven response bias as long as reward was accessible. However, stimuli with a history of reward did not interfere with goal-directed action and inhibition in a subsequent task after removal of the reward incentives. While the first experiment was not conclusive regarding an impact of reward-associated cues on response inhibition, the second experiment, validated by Bayesian statistics, clearly questioned an effect of reward history on inhibitory control. This stands in contrast to earlier findings suggesting that the effect of reward history on subsequent action control is not as consistent as previously assumed. Our results show that participants are able to overcome influences from Pavlovian learning in a simple inhibition task. We discuss our findings with respect to features of the experimental design which may help or complicate overcoming behavioural biases induced by reward history.


Assuntos
Inibição Psicológica , Recompensa , Teorema de Bayes , Condicionamento Clássico , Sinais (Psicologia) , Humanos , Aprendizagem
4.
Atten Percept Psychophys ; 80(6): 1436-1448, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29675555

RESUMO

In past years, an extensive amount of research has focused on how past experiences guide future attention. Humans automatically attend to stimuli previously associated with reward and stimuli that have been experienced during visual search, even when it is disadvantageous in present situations. Recently, the relationship between "reward history" and "search history" has been discussed critically. We review results from research on value-driven attentional capture (VDAC) with a focus on these two experience-based attentional selection processes and their distinction. To clarify inconsistencies, we examined VDAC within a design that allows a direct comparison with other mechanisms of attentional selection. Eighty-four healthy adults were trained to incidentally associate colors with reward (10 cents, 2 cents) or with no reward. In a subsequent visual search task, distraction by reward-associated and unrewarded stimuli was contrasted. In the training phase, reward signals facilitated performance. When these value-signaling stimuli appeared as distractors in the test phase, they continuously shaped attentional selection, despite their task irrelevance. Our findings clearly cannot be attributed to a history of target search. We conclude that once an association is established, value signals guide attention automatically in new situations, which can be beneficial or not, depending on the congruency with current goals.


Assuntos
Viés de Atenção , Recompensa , Adolescente , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
5.
Atten Percept Psychophys ; 79(7): 1871-1877, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28785966

RESUMO

Contextual cueing can be enhanced by reward. However, there is a debate if reward is associated with the repeated target-distractor configurations or with the repeated target locations that occur in both repeated and new displays. Based on neuroimaging evidence, we hypothesized that reward becomes associated with the target location only in new displays, but not in repeated displays, where the repeated target location is overshadowed by the more salient repeated target-distractor configuration. To test this hypothesis, we varied the reward value associated with the same target location in repeated and new displays. The results confirmed the overshadowing hypothesis in that search facilitation in repeated target-distractor configurations was modulated by the variable value associated with the target location. This effect was observed mainly in early learning.


Assuntos
Sinais (Psicologia) , Aprendizagem , Recompensa , Adulto , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 112(24): 7593-8, 2015 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-26034283

RESUMO

Better-performing younger adults typically express greater brain signal variability relative to older, poorer performers. Mechanisms for age and performance-graded differences in brain dynamics have, however, not yet been uncovered. Given the age-related decline of the dopamine (DA) system in normal cognitive aging, DA neuromodulation is one plausible mechanism. Hence, agents that boost systemic DA [such as d-amphetamine (AMPH)] may help to restore deficient signal variability levels. Furthermore, despite the standard practice of counterbalancing drug session order (AMPH first vs. placebo first), it remains understudied how AMPH may interact with practice effects, possibly influencing whether DA up-regulation is functional. We examined the effects of AMPH on functional-MRI-based blood oxygen level-dependent (BOLD) signal variability (SD(BOLD)) in younger and older adults during a working memory task (letter n-back). Older adults expressed lower brain signal variability at placebo, but met or exceeded young adult SD(BOLD) levels in the presence of AMPH. Drug session order greatly moderated change-change relations between AMPH-driven SD(BOLD) and reaction time means (RT(mean)) and SDs (RT(SD)). Older adults who received AMPH in the first session tended to improve in RT(mean) and RT(SD) when SD(BOLD) was boosted on AMPH, whereas younger and older adults who received AMPH in the second session showed either a performance improvement when SD(BOLD) decreased (for RT(mean)) or no effect at all (for RT(SD)). The present findings support the hypothesis that age differences in brain signal variability reflect aging-induced changes in dopaminergic neuromodulation. The observed interactions among AMPH, age, and session order highlight the state- and practice-dependent neurochemical basis of human brain dynamics.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Dextroanfetamina/farmacologia , Memória de Curto Prazo/efeitos dos fármacos , Adulto , Idoso , Dopamina/fisiologia , Método Duplo-Cego , Feminino , Neuroimagem Funcional , Humanos , Análise dos Mínimos Quadrados , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Modelos Psicológicos , Análise Multivariada , Adulto Jovem
7.
J Neurosci ; 33(43): 17150-9, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24155318

RESUMO

The comprehensive relations between healthy adult human brain white matter (WM) microstructure and gray matter (GM) function, and their joint relations to cognitive performance, remain poorly understood. We investigated these associations in 27 younger and 28 older healthy adults by linking diffusion tensor imaging (DTI) with functional magnetic resonance imaging (fMRI) data collected during an n-back working memory task. We present a novel application of multivariate Partial Least Squares (PLS) analysis that permitted the simultaneous modeling of relations between WM integrity values from all major WM tracts and patterns of condition-related BOLD signal across all GM regions. Our results indicate that greater microstructural integrity of the major WM tracts was negatively related to condition-related blood oxygenation level-dependent (BOLD) signal in task-positive GM regions. This negative relationship suggests that better quality of structural connections allows for more efficient use of task-related GM processing resources. Individuals with more intact WM further showed greater BOLD signal increases in typical "task-negative" regions during fixation, and notably exhibited a balanced magnitude of BOLD response across task-positive and -negative states. Structure-function relations also predicted task performance, including accuracy and speed of responding. Finally, structure-function-behavior relations reflected individual differences over and above chronological age. Our findings provide evidence for the role of WM microstructure as a scaffold for the context-relevant utilization of GM regions.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia
8.
Neurobiol Aging ; 34(1): 358.e1-10, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22939506

RESUMO

Aging compromises dopamine transporter (DAT) and receptor mechanisms in the frontostriatal circuitry. In a sample of 1288 younger and older adults, we investigated (i) whether individual differences in genotypes of the DAT gene (i.e., SLC6A3, the DAT variable number of tandem repeat 9/9, 9/10, and 10/10) and in the D2 receptor (DRD2) gene (i.e., the C957T [rs6277] CC and any T) interactively contribute to phenotype variations in episodic memory performance; and (ii) whether these genetic effects are magnified in older adults, because of considerable declines in the dopamine functions. Our results showed that carrying genotypes associated with higher levels of striatal synaptic dopamine (DAT 9/9) and higher density of extrastriatal D2 receptors (C957T CC) were associated with better backward serial recall, an episodic memory task with high encoding and retrieval demands. Critically, the gene-gene interaction effect was reliably stronger in older than in younger adults. In line with the resource modulation hypothesis, our findings suggest that aging-related decline in brain phenotypes (e.g., dopamine functions) could alter the relations between genotypes and behavioral phenotypes (e.g., episodic memory).


Assuntos
Envelhecimento , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Memória/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Dopamina D2/genética , Adulto , Idoso , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estatísticas não Paramétricas , Adulto Jovem
9.
Hum Brain Mapp ; 33(7): 1607-20, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21739526

RESUMO

Executive functions that are dependent upon the frontal-parietal network decline considerably during the course of normal aging. To delineate neuroanatomical correlates of age-related executive impairment, we investigated the relation between cortical thickness and executive functioning in 73 younger (20-32 years) and 56 older (60-71 years) healthy adults. Executive functioning was assessed using the Wisconsin Card Sorting Test (WCST). Cortical thickness was measured at each location of the cortical mantle using surface-based segmentation procedures on high-resolution T1-weighted magnetic resonance images. For regions involved in WCST performance, such as the lateral prefrontal and parietal cortices, we found that thicker cortex was related to higher accuracy. Follow-up ROI-based analyses revealed that these associations were stronger in older than in younger adults. Moreover, among older adults, high and low performers differed in cortical thickness within regions generally linked to WCST performance. Our results indicate that the structural cortical correlates of executive functioning largely overlap with previously identified functional patterns. We conclude that structural preservation of relevant brain regions is associated with higher levels of executive performance in old age, and underscore the need to consider the heterogeneity of brain aging in relation to cognitive functioning.


Assuntos
Envelhecimento/fisiologia , Córtex Cerebral/fisiologia , Função Executiva/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia , Adulto , Idoso , Envelhecimento/patologia , Córtex Cerebral/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
J Cogn Neurosci ; 23(8): 2030-45, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20828302

RESUMO

Individual differences in working memory (WM) performance have rarely been related to individual differences in the functional responsivity of the WM brain network. By neglecting person-to-person variation, comparisons of network activity between younger and older adults using functional imaging techniques often confound differences in activity with age trends in WM performance. Using functional magnetic resonance imaging, we investigated the relations among WM performance, neural activity in the WM network, and adult age using a parametric letter n-back task in 30 younger adults (21-31 years) and 30 older adults (60-71 years). Individual differences in the WM network's responsivity to increasing task difficulty were related to WM performance, with a more responsive BOLD signal predicting greater WM proficiency. Furthermore, individuals with higher WM performance showed greater change in connectivity between left dorsolateral prefrontal cortex and left premotor cortex across load. We conclude that a more responsive WM network contributes to higher WM performance, regardless of adult age. Our results support the notion that individual differences in WM performance are important to consider when studying the WM network, particularly in age-comparative studies.


Assuntos
Envelhecimento/fisiologia , Mapeamento Encefálico , Encéfalo/irrigação sanguínea , Memória de Curto Prazo/fisiologia , Adulto , Fatores Etários , Idoso , Análise de Variância , Encéfalo/fisiologia , Sinais (Psicologia) , Feminino , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Individualidade , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/irrigação sanguínea , Rede Nervosa/fisiologia , Testes Neuropsicológicos , Oxigênio/sangue , Psicofísica , Tempo de Reação/fisiologia , Fatores de Tempo , Adulto Jovem
11.
J Cogn Neurosci ; 22(5): 875-87, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19413475

RESUMO

Neurophysiological data suggest that the integration of prior information and incoming sensory evidence represents the neural basis of the decision-making process. Here, we aimed to identify the brain structures involved in the integration of prior information about the average magnitude of a stimulus set and current sensory evidence. Specifically, we investigated whether prior average information already biases vibrotactile decision making during stimulus perception and maintenance before the comparison process. For this purpose, we used a vibrotactile delayed discrimination task and fMRI. At the behavioral level, participants showed the time-order effect. This psychophysical phenomenon has been shown to result from the influence of prior information on the perception of and the memory for currently presented stimuli. Similarly, the fMRI signal reflected the integration of prior information about the average vibration frequency and the currently presented vibration frequency. During stimulus encoding, the fMRI signal in primary and secondary somatosensory (S2) cortex, thalamus, and ventral premotor cortex mirrored an integration process. During stimulus maintenance, only a region in the intraparietal sulcus showed this modulation by prior average information. Importantly, the fMRI signal in S2 and intraparietal sulcus correlated with individual differences in the degree to which participants integrated prior average information. This strongly suggests that these two regions play a pivotal role in the integration process. Taken together, these results support the notion that the integration of current sensory and prior average information is a major feature of how the human brain perceives, remembers, and judges magnitude stimuli.


Assuntos
Viés , Tomada de Decisões/fisiologia , Percepção do Tato/fisiologia , Tato/fisiologia , Vibração , Vias Aferentes/irrigação sanguínea , Vias Aferentes/fisiologia , Mapeamento Encefálico , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/fisiologia , Discriminação Psicológica/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Testes Neuropsicológicos , Oxigênio/sangue , Estimulação Física/métodos , Psicofísica/métodos , Estatística como Assunto
12.
Neuropsychologia ; 48(2): 402-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19804789

RESUMO

Individual differences in episodic memory are highly heritable. Several studies have linked a polymorphism in the gene encoding the KIBRA protein to episodic memory performance. Results regarding CLSTN2, the gene encoding the synaptic protein calsyntenin 2, have been less consistent, possibly pointing to interactions with other genes. Given that both KIBRA and CLSTN2 are expressed in the medial temporal lobe and have been linked to synaptic plasticity, we investigated whether KIBRA and CLSTN2 interactively modulate episodic memory performance (n=383). We replicated the beneficial effect of the KIBRA T-allele on episodic memory, and discovered that this effect increases with the associative demands of the memory task. Importantly, the memory-enhancing effect of the KIBRA T-allele was boosted by the presence of the CLSTN2 C-allele, which positively affected memory performance in some previous studies. In contrast, the presence of CLSTN2 C-allele led to reduced performance in subjects homozygous for the KIBRA C-allele. Overall, these findings suggest that KIBRA and CLSTN2 interactively modulate episodic memory performance, and underscore the need for delineating the interactive effects of multiple genes on brain and behavior.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Proteínas de Membrana/genética , Memória/fisiologia , Polimorfismo Genético/genética , Proteínas/genética , Adulto , Aprendizagem por Associação/fisiologia , Cognição/fisiologia , Função Executiva/fisiologia , Feminino , Frequência do Gene , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Testes Neuropsicológicos , Fosfoproteínas , Fatores Sexuais , Adulto Jovem
13.
Proc Natl Acad Sci U S A ; 106(52): 22552-7, 2009 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20018709

RESUMO

Working memory (WM) shows pronounced age-related decline. Functional magnetic resonance imaging (fMRI) studies have revealed age differences in task-related brain activation. Evidence based primarily on episodic memory studies suggests that brain activation patterns can be modulated by task difficulty in both younger and older adults. In most fMRI aging studies on WM, however, performance level has not been considered, so that age differences in activation patterns are confounded with age differences in performance level. Here, we address this issue by comparing younger and older low and high performers in an event-related fMRI study. Thirty younger (20-30 years) and 30 older (60-70 years) healthy adults were tested with a spatial WM task with three load levels. A region-of-interest analysis revealed marked differences in the activation patterns between high and low performers in both age groups. Critically, among the older adults, a more "youth-like" load-dependent modulation of the blood oxygen level-dependent signal was associated with higher levels of spatial WM performance. These findings underscore the need of taking performance level into account when studying changes in functional brain activation patterns from early to late adulthood.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Encéfalo/fisiologia , Memória/fisiologia , Adulto , Idoso , Encéfalo/anatomia & histologia , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Córtex Motor/anatomia & histologia , Córtex Motor/fisiologia , Rede Nervosa/anatomia & histologia , Rede Nervosa/fisiologia , Lobo Parietal/anatomia & histologia , Lobo Parietal/fisiologia , Análise e Desempenho de Tarefas , Adulto Jovem
14.
Cereb Cortex ; 18(11): 2686-700, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18372293

RESUMO

Recent studies investigating the influence of spatial-selective attention on primary somatosensory processing have produced inconsistent results. The aim of this study was to explore the influence of tactile spatial-selective attention on spatiotemporal aspects of evoked neuronal activity in the primary somatosensory cortex (S1). We employed simultaneous electroencephalography (EEG)-functional magnetic resonance imaging (fMRI) in 14 right-handed subjects during bilateral index finger Braille stimulation to investigate the relationship between attentional effects on somatosensory evoked potential (SEP) components and the blood oxygenation level-dependent (BOLD) signal. The 1st reliable EEG response following left tactile stimulation (P50) was significantly enhanced by spatial-selective attention, which has not been reported before. FMRI analysis revealed increased activity in contralateral S1. Remarkably, the effect of attention on the P50 component as well as long-latency SEP components starting at 190 ms for left stimuli correlated with attentional effects on the BOLD signal in contralateral S1. The implications are 2-fold: First, the correlation between early and long-latency SEP components and the BOLD effect suggest that spatial-selective attention enhances processing in S1 at 2 time points: During an early passage of the signal and during a later passage, probably via re-entrant feedback from higher cortical areas. Second, attentional modulations of the fast electrophysiological signals and the slow hemodynamic response are linearly related in S1.


Assuntos
Atenção/fisiologia , Potenciais Somatossensoriais Evocados/fisiologia , Córtex Somatossensorial/fisiologia , Percepção Espacial/fisiologia , Tato/fisiologia , Adulto , Eletroencefalografia , Feminino , Dedos/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos , Probabilidade , Adulto Jovem
15.
Neuroimage ; 37(2): 410-21, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17566768

RESUMO

The neural systems regulating food intake in obese individuals remain poorly understood. Previous studies applied positron emission tomography and manipulated hunger and satiety to investigate differences in appetitive processing between obese and normal-weight individuals. However, it is not known whether manipulation of stimulus value may yield different neural activity in obese as compared to control subjects when intrinsic physiological states are kept constant. We used functional magnetic resonance imaging to investigate 13 obese and 13 normal-weight subjects and manipulated food motivation by presenting visual food stimuli differing in their caloric content and energy density. In contrast to controls, obese women selectively activated the dorsal striatum while viewing high-caloric foods. Moreover, in the high-calorie condition body mass index (BMI) predicted activation in the dorsal striatum, anterior insula, claustrum, posterior cingulate, postcentral and lateral orbitofrontal cortex. The results indicate that in obese individuals simple visual stimulation with food stimuli activates regions related to reward anticipation and habit learning (dorsal striatum). Additionally, high-calorie food images yielded BMI-dependent activations in regions associated with taste information processing (anterior insula and lateral orbitofrontal cortex), motivation (orbitofrontal cortex), emotion as well as memory functions (posterior cingulate). Collectively, the results suggest that the observed activation is independent of the physiological states of hunger and satiation, and thus may contribute to pathological overeating and obesity. Some of the observed activations (dorsal striatum, orbitofrontal cortex) are likely to be dopamine-mediated.


Assuntos
Mapeamento Encefálico , Corpo Estriado/fisiologia , Alimentos , Obesidade/fisiopatologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Estimulação Luminosa
16.
J Neurosci ; 26(51): 13231-9, 2006 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-17182773

RESUMO

Recent neurophysiological studies in macaques identified a network of brain regions related to vibrotactile working memory (WM), including somatosensory, motor, premotor, and prefrontal cortex. In these studies, monkeys decided which of two vibrotactile stimuli that were sequentially applied to their fingertips and separated by a short delay had the higher vibration frequency. Using the same task, the objective of the present study was to identify the neural correlates related to the different task periods (encoding, maintenance, and decision making) of vibrotactile WM in the human brain. For this purpose, we used event-related functional magnetic resonance imaging and contrasted WM trials with a control condition of vibrotactile stimulation that did not require maintenance and decision making. We found that vibrotactile WM has a similar but not identical neural organization in humans and monkeys. Consistent with neurophysiological data in monkeys and behavioral studies in humans, the primary somatosensory and the ventral premotor cortex exhibited increased activity during encoding. Maintenance of a vibrotactile memory trace evoked activity in the premotor and ventrolateral prefrontal cortex. Decision making caused activation in the somatosensory, premotor, and lateral prefrontal cortex. However, human vibrotactile WM recruited additional areas. Decision making activated a broader network than that studied thus far in monkeys. Maintenance and decision making additionally activated the inferior parietal lobe. Although the different task components evoked activity in distinctive neural networks, there was considerable overlap of activity, especially regarding maintenance and decision making, indicating that similar neural mechanisms are required for the subprocesses related to these task components.


Assuntos
Encéfalo/fisiologia , Memória/fisiologia , Rede Nervosa/fisiologia , Tato/fisiologia , Vibração , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Desempenho Psicomotor/fisiologia , Fatores de Tempo
17.
J Affect Disord ; 75(3): 223-35, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12880935

RESUMO

BACKGROUND: The prevalence of major depression for women is about twice that for men. This gender difference in prevalence rates has led to much research addressing gender differences in the presentation and features of major depression, and, to a lesser extent, research addressing gender differences in treatment response and personality. However, studies differ considerably in the population sampled, and findings vary significantly. In the current retrospective examination of data, we investigated all of these variables in one single sample of outpatients with major depression seen in a tertiary care centre. METHODS: A sample of 139 men and 246 women with major depression receiving antidepressant treatment (SSRIs, TCAs, SNRIs, MAOIs, or RIMAs) in an outpatient setting were contrasted with regard to symptoms and severity of depression, course of illness, treatment response, and personality. RESULTS: Women were found to experience more vegetative and atypical symptoms, anxiety, and anger than men, and to report higher severity of depression on self-report measures. Regarding personality, women scored higher on conscientiousness, the extraversion facet warmth, the openness facet feelings, and sociotropy. Effect sizes were small to moderate. No differences were found in the course of the illness and treatment response. LIMITATIONS: Findings are not generalizable to inpatient or community samples, and some of the gender differences may be accounted for by gender differences in treatment seeking behaviour. CONCLUSIONS: While men and women receiving antidepressant treatment show some gender differences in the psychopathology of major depression, these differences do not appear to translate into differences in response to antidepressants. Gender differences in personality appear less profound than in the average population, indicating the potential role of a certain personality type that predisposes individuals to develop clinical depression, independent of gender. CLINICAL RELEVANCE: The current examination underscores the role gender plays in the presentation and treatment of major depression.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Adolescente , Adulto , Antidepressivos/classificação , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inventário de Personalidade , Prevalência , Índice de Gravidade de Doença , Distribuição por Sexo , Transtornos Somatoformes/epidemiologia , Transtornos Somatoformes/psicologia
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