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1.
Front Psychiatry ; 15: 1362188, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757137

RESUMO

Introduction: Self-harming behavior in prisoners is a prevalent phenomenon, with international studies estimating a 4% prevalence rate. However, studies on self-injurious behavior in the German prison system are currently lacking. Therefore, our study aims to conduct an initial assessment. Methods: The Criminological Service for the Berlin Prison System distributed questionnaires on incidents of self-harm to all Berlin prisons, except for juvenile detention centers. The questionnaires were supplemented with medical data, such as psychiatric diagnoses and medication. Results: 62 questionnaires were returned, which could be attributed to 52 inmates. Compared to the average population in the Berlin prison system, the study sample exhibited variations in age, gender distribution and nationality. 94% of the inmates received a psychiatric diagnosis. Two-thirds of the male inmates had substance use disorders, while 83% of the female inmates had emotionally unstable personality resp. borderline disorders. Prior to self-harm, 87% of the inmates were administered psychiatric medication. Discussion: Our study found similarities between the study population and international studies in the distribution of certain characteristics. We assume that many of the postulated risk factors can also apply to Berlin prisoners. However, the study is limited by the small number of cases and the absence of a control group.

2.
Front Neurosci ; 17: 1218510, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901437

RESUMO

Introduction: Sensory inference and top-down predictive processing, reflected in human neural activity, play a critical role in higher-order cognitive processes, such as language comprehension. However, the neurobiological bases of predictive processing in higher-order cognitive processes are not well-understood. Methods: This study used electroencephalography (EEG) to track participants' cortical dynamics in response to Austrian Sign Language and reversed sign language videos, measuring neural coherence to optical flow in the visual signal. We then used machine learning to assess entropy-based relevance of specific frequencies and regions of interest to brain state classification accuracy. Results: EEG features highly relevant for classification were distributed across language processing-related regions in Deaf signers (frontal cortex and left hemisphere), while in non-signers such features were concentrated in visual and spatial processing regions. Discussion: The results highlight functional significance of predictive processing time windows for sign language comprehension and biological motion processing, and the role of long-term experience (learning) in minimizing prediction error.

3.
Int J Behav Dev ; 45(5): 397-408, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34690387

RESUMO

Acquisition of natural language has been shown to fundamentally impact both one's ability to use the first language, and the ability to learn subsequent languages later in life. Sign languages offer a unique perspective on this issue, because Deaf signers receive access to signed input at varying ages. The majority acquires sign language in (early) childhood, but some learn sign language later - a situation that is drastically different from that of spoken language acquisition. To investigate the effect of age of sign language acquisition and its potential interplay with age in signers, we examined grammatical acceptability ratings and reaction time measures in a group of Deaf signers (age range: 28-58 years) with early (0-3 years) or later (4-7 years) acquisition of sign language in childhood. Behavioral responses to grammatical word order variations (subject-object-verb vs. object-subject-verb) were examined in sentences that included: 1) simple sentences, 2) topicalized sentences, and 3) sentences involving manual classifier constructions, uniquely characteristic of sign languages. Overall, older participants responded more slowly. Age of acquisition had subtle effects on acceptability ratings, whereby the direction of the effect depended on the specific linguistic structure.

4.
Sci Data ; 8(1): 136, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34021166

RESUMO

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.


Assuntos
Biodiversidade , Oligoquetos/classificação , Animais , Biomassa
5.
J Neural Eng ; 18(2)2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33440368

RESUMO

Objective.Understanding and differentiating brain states is an important task in the field of cognitive neuroscience with applications in health diagnostics, such as detecting neurotypical development vs. autism spectrum or coma/vegetative state vs. locked-in state. Electroencephalography (EEG) analysis is a particularly useful tool for this task as EEG data can detect millisecond-level changes in brain activity across a range of frequencies in a non-invasive and relatively inexpensive fashion. The goal of this study is to apply machine learning methods to EEG data in order to classify visual language comprehension across multiple participants.Approach.26-channel EEG was recorded for 24 Deaf participants while they watched videos of sign language sentences played in time-direct and time-reverse formats to simulate interpretable vs. uninterpretable sign language, respectively. Sparse optimal scoring (SOS) was applied to EEG data in order to classify which type of video a participant was watching, time-direct or time-reversed. The use of SOS also served to reduce the dimensionality of the features to improve model interpretability.Main results.The analysis of frequency-domain EEG data resulted in an average out-of-sample classification accuracy of 98.89%, which was far superior to the time-domain analysis. This high classification accuracy suggests this model can accurately identify common neural responses to visual linguistic stimuli.Significance.The significance of this work is in determining necessary and sufficient neural features for classifying the high-level neural process of visual language comprehension across multiple participants.


Assuntos
Compreensão , Eletroencefalografia , Encéfalo/fisiologia , Humanos , Idioma , Aprendizado de Máquina
6.
J Exp Psychol Learn Mem Cogn ; 47(6): 998-1011, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33211523

RESUMO

Nonsigners viewing sign language are sometimes able to guess the meaning of signs by relying on the overt connection between form and meaning, or iconicity (cf. Ortega, Özyürek, & Peeters, 2020; Strickland et al., 2015). One word class in sign languages that appears to be highly iconic is classifiers: verb-like signs that can refer to location change or handling. Classifier use and meaning are governed by linguistic rules, yet in comparison with lexical verb signs, classifiers are highly variable in their morpho-phonology (variety of potential handshapes and motion direction within the sign). These open-class linguistic items in sign languages prompt a question about the mechanisms of their processing: Are they part of a gestural-semiotic system (processed like the gestures of nonsigners), or are they processed as linguistic verbs? To examine the psychological mechanisms of classifier comprehension, we recorded the electroencephalogram (EEG) activity of signers who watched videos of signed sentences with classifiers. We manipulated the sentence word order of the stimuli (subject-object-verb [SOV] vs. object-subject-verb [OSV]), contrasting the two conditions, which, according to different processing hypotheses, should incur increased processing costs for OSV orders. As previously reported for lexical signs, we observed an N400 effect for OSV compared with SOV, reflecting increased cognitive load for linguistic processing. These findings support the hypothesis that classifiers are a linguistic part of speech in sign language, extending the current understanding of processing mechanisms at the interface of linguistic form and meaning. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Psicolinguística , Língua de Sinais , Adulto , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Front Psychiatry ; 11: 794, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32903474

RESUMO

BACKGROUND: Among people living in detention, substance use is highly prevalent, including opioid dependence. Opioid agonist treatment (OAT) has been established as an evidence-based, first-line treatment for opioid dependence. Despite high prevalence of opioid dependence, conclusive data regarding its prevalence and the OAT practice in German prisons is scarce; rather, the existing data widely diverges concerning the rates of people in detention receiving OAT. MATERIALS AND METHODS: We conducted a cross-sectional survey of all detention facilities in Berlin. On the date of data collection, a full census of the routine records was completed based on the medical documentation system. For each opioid dependent individual, we extracted sociodemographic data (i.e., age, sex, and non-/German nationality, whether people experienced language-related communication barriers), information about OAT, comorbidities (HIV, hepatitis C, schizophrenia), and the detention center, as well as the anticipated imprisonment duration and sentence type. The data was first analyzed descriptively and secondly in an evaluative-analytical manner by analyzing factors that influence the access to OAT of people living in detention. RESULTS: Among the 4,038 people in detention in the Berlin custodial setting under investigation, we identified a 16% prevalence of opioid dependence. Of the opioid-dependent individuals, 42% received OAT; 31% were treated with methadone, 55% were treated with levomethadone, and 14% were treated with buprenorphine. Access to OAT seemed mainly dependent upon initial receipt of OAT at the time of imprisonment, detention duration, the prisons in which individuals were detained, German nationality, and sex. The overall prevalence of HIV was 4-8%, hepatitis C was 31-42%, and schizophrenia was 5%. CONCLUSIONS: The prevalence of opioid dependence and access to OAT remains a major health issue in the custodial setting. OAT implementation must be especially intensified among male, non-German, opioid-dependent individuals with a short detention period. Treatment itself must be diversified regarding the substances used for OAT, and institutional treatment differences suggest the need for a consistent treatment approach and the standardized implementation of treatment guidelines within local prison's standard operating procedures. Testing for infectious diseases should be intensified among opioid-dependent people living in detention to address scarcely known infection statuses and high infection rates.

8.
Behav Sci Law ; 38(5): 482-492, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32833256

RESUMO

Surveys confirm risk factors for the incarceration of patients with psychosis including homelessness and comorbidity. There is also agreement that severe psychosis can lead to violence. Data describing prisoners with psychosis in Germany are scarce. We aimed to compare patients with psychosis in a prison hospital and patients with psychosis in a community hospital. Demographic data were collected, as well as comorbidity in the form of substance dependence and a psychiatric assessment using the German version of the 18-item Brief Psychiatric Rating Scale (BPRS) and the Positive and Negative Syndrome Scale (PANSS). In the prison hospital group more patients were homeless (17 versus 2%) and non-German (36 versus 4%). There were also more patients with substance dependence or abuse in the prison hospital group. The total scores of BPRS and PANSS were lower in the prison hospital group (BPRS, 43.8 versus 51.2; PANSS, 71.5 versus 83.7). We assume that social disintegration for mentally disturbed offenders prior to incarceration hindered effective treatment. To avoid further social disintegration and possible further deterioration of mental health status of released offenders, which may lead to reoffending after imprisonment, discharge management after release from prison should be improved.


Assuntos
Hospitais Comunitários , Hospitais Psiquiátricos , Pacientes Internados/psicologia , Prisioneiros/psicologia , Prisões , Transtornos Psicóticos/epidemiologia , Adulto , Escalas de Graduação Psiquiátrica Breve/estatística & dados numéricos , Comorbidade , Alemanha/epidemiologia , Pessoas Mal Alojadas/psicologia , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , Prisioneiros/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Violência/psicologia
9.
Behav Sci Law ; 38(5): 471-481, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32633430

RESUMO

The risk of violent behavior is known to be higher for patients who suffer from a severe mental disorder. However, specific prediction tools for clinical work in prison psychiatry are lacking. In this single-center study, two violence risk assessment tools (Forensic Psychiatry and Violence Tool, "FoVOx," and Mental Illness and Violence Tool, "OxMIV") were applied to a prison hospital population with a primary psychotic or bipolar disorder and subsequently compared. The required information on all items of both tools was obtained retrospectively for a total of 339 patients by evaluation of available patient files. We obtained the median and inter-quartile range for both FoVOx and OxMIV, and their rank correlation coefficient along with 95% confidence intervals (CIs)-for the full cohort, as well as for cohort subgroups. The two risk assessment tools were strongly positively correlated (Spearman correlation = 0.83; 95% CI = 0.80-0.86). Such a high correlation was independent of nationality, country of origin, type of detention, schizophrenia-spectrum disorder, previous violent crime and alcohol use disorder, where correlations were above 0.8. A lower correlation was seen with patients who were 30 years old or more, married, with affective disorder and with self-harm behavior, and also in patients without aggressive behavior and without drug use disorder. Both risk assessment tools are applicable as an adjunct to clinical decision making in prison psychiatry.


Assuntos
Psiquiatria Legal/instrumentação , Prisioneiros/psicologia , Medição de Risco/métodos , Violência/psicologia , Adolescente , Adulto , Idoso , Berlim/epidemiologia , Transtorno Bipolar/diagnóstico , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Prisioneiros/estatística & dados numéricos , Transtornos Psicóticos/diagnóstico , Estudos Retrospectivos , Violência/estatística & dados numéricos
10.
Brain Lang ; 200: 104708, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31698097

RESUMO

One of the key questions in the study of human language acquisition is the extent to which the development of neural processing networks for different components of language are modulated by exposure to linguistic stimuli. Sign languages offer a unique perspective on this issue, because prelingually Deaf children who receive access to complex linguistic input later in life provide a window into brain maturation in the absence of language, and subsequent neuroplasticity of neurolinguistic networks during late language learning. While the duration of sensitive periods of acquisition of linguistic subsystems (sound, vocabulary, and syntactic structure) is well established on the basis of L2 acquisition in spoken language, for sign languages, the relative timelines for development of neural processing networks for linguistic sub-domains are unknown. We examined neural responses of a group of Deaf signers who received access to signed input at varying ages to three linguistic phenomena at the levels of classifier signs, syntactic structure, and information structure. The amplitude of the N400 response to the marked word order condition negatively correlated with the age of acquisition for syntax and information structure, indicating increased cognitive load in these conditions. Additionally, the combination of behavioral and neural data suggested that late learners preferentially relied on classifiers over word order for meaning extraction. This suggests that late acquisition of sign language significantly increases cognitive load during analysis of syntax and information structure, but not word-level meaning.


Assuntos
Envelhecimento , Surdez/fisiopatologia , Surdez/psicologia , Eletroencefalografia , Desenvolvimento da Linguagem , Aprendizagem/fisiologia , Linguística , Língua de Sinais , Adulto , Potenciais Evocados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasticidade Neuronal , Vocabulário
11.
Science ; 366(6464): 480-485, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31649197

RESUMO

Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide.


Assuntos
Biodiversidade , Oligoquetos , Distribuição Animal , Animais , Biomassa , Clima , Planeta Terra , Ecossistema , Modelos Lineares , Modelos Biológicos , Solo
12.
Lang Speech ; 62(4): 652-680, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30354860

RESUMO

Previous studies of Austrian Sign Language (ÖGS) word-order variations have demonstrated the human processing system's tendency to interpret a sentence-initial (case-) ambiguous argument as the subject of the clause ("subject preference"). The electroencephalogram study motivating the current report revealed earlier reanalysis effects for object-subject compared to subject-object sentences, in particular, before the start of the movement of the agreement marking sign. The effects were bound to time points prior to when both arguments were referenced in space and/or the transitional hand movement prior to producing the disambiguating sign. Due to the temporal proximity of these time points, it was not clear which visual cues led to disambiguation; that is, whether non-manual markings (body/shoulder/head shift towards the subject position) or the transitional hand movement resolved ambiguity. The present gating study further supports that disambiguation in ÖGS is triggered by cues occurring before the movement of the disambiguating sign. Further, the present study also confirms the presence of the subject preference in ÖGS, showing again that signers and speakers draw on similar strategies during language processing independent of language modality. Although the ultimate role of the visual cues leading to disambiguation (i.e., non-manual markings and transitional movements) requires further investigation, the present study shows that they contribute crucial information about argument structure during online processing. This finding provides strong support for granting these cues some degree of linguistic status (at least in ÖGS).


Assuntos
Linguística , Movimento , Língua de Sinais , Áustria , Sinais (Psicologia) , Eletroencefalografia , Feminino , Humanos , Idioma , Masculino , Estimulação Luminosa , Fatores de Tempo
13.
Brain Res ; 1691: 105-117, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29627484

RESUMO

Research on spoken languages has identified a "subject preference" processing strategy for tackling input that is syntactically ambiguous as to whether a sentence-initial NP is a subject or object. The present study documents that the "subject preference" strategy is also seen in the processing of a sign language, supporting the hypothesis that the "subject"-first strategy is universal and not dependent on the language modality (spoken vs. signed). Deaf signers of Austrian Sign Language (ÖGS) were shown videos of locally ambiguous signed sentences in SOV and OSV word orders. Electroencephalogram (EEG) data indicated higher cognitive load in response to OSV stimuli (i.e. a negativity for OSV compared to SOV), indicative of syntactic reanalysis cost. A finding that is specific to the visual modality is that the ERP (event-related potential) effect reflecting linguistic reanalysis occurred earlier than might have been expected, that is, before the time point when the path movement of the disambiguating sign was visible. We suggest that in the visual modality, transitional movement of the articulators prior to the disambiguating verb position or co-occurring non-manual (face/body) markings were used in resolving the local ambiguity in ÖGS. Thus, whereas the processing strategy of "subject preference" is cross-modal at the linguistic level, the cues that enable the processor to apply that strategy differ in signing as compared to speech.


Assuntos
Compreensão/fisiologia , Potenciais Evocados/fisiologia , Linguística , Língua de Sinais , Fala , Encéfalo/fisiologia , Eletroencefalografia , Feminino , Humanos , Idioma , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Fatores de Tempo
14.
J Cancer ; 7(5): 555-68, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27053954

RESUMO

BACKGROUND: Malignant melanoma is an aggressive type of skin cancer with high risk for metastasis and chemoresistance. Disruption of tightly regulated processes such as cell cycle, cell adhesion, cell differentiation and cell death are predominant in melanoma development. So far, conventional treatment options have been insufficient to treat metastatic melanoma and survival rates are poor. Anthraquinone compounds have been reported to have anti-tumorigenic potential by DNA-interaction, promotion of apoptosis and suppression of proliferation in various cancer cells. METHODS: In the current study, the racemic tetrahydroanthraquinone derivative (±)-4-deoxyaustrocortilutein (4-DACL) was synthesized and the cytotoxic activity against melanoma cells and melanoma spheroids determined by CellTiter-Blue viability Assay and phase contrast microscopy. Generation of reactive oxygen species (ROS) was determined with CellROX Green and Deep Red Reagent kit and microplate-based fluorometry. Luciferase reporter gene assays for nuclear factor kappa B (NF-κB) and p53 activities and western blotting analysis were carried out to detect the expression of anti-proliferative or pro-apoptotic (p53, p21, p27, MDM2, and GADD45M) and anti-apoptotic (p65, IκB-α, IKK) proteins. Cell cycle distribution and apoptosis rate were detected by flow cytometry, the morphological changes visualized by fluorescence microscopy and the activation of different caspase cascades distinguished by Caspase Glo 3/7, 8 and 9 Assays. RESULTS: We demonstrated that 4-DACL displayed high activity against different malignant melanoma cells and melanoma spheroids and only low toxicity to melanocytes and other primary cells. In particular, 4-DACL treatment induced mitochondrial ROS, reduced NF-κB signaling activity and increased up-regulation of the cell cycle inhibitors cyclin-dependent kinase inhibitor p21 (p21(WAF1/Cip1)) and the tumor suppressor protein p53 in a dose-dependent manner, which was accompanied by decreased cell proliferation and apoptosis via the intrinsic pathway. CONCLUSION: According to these results, we suggest that 4-DACL may be a promising therapeutic agent for the treatment of malignant melanoma.

15.
Ann Neurol ; 78(2): 235-47, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25940842

RESUMO

OBJECTIVE: Even though wakefulness at night leads to profound performance deterioration and is regularly experienced by shift workers, its cerebral correlates remain virtually unexplored. METHODS: We assessed brain activity in young healthy adults during a vigilant attention task under high and low sleep pressure during night-time, coinciding with strongest circadian sleep drive. We examined sleep-loss-related attentional vulnerability by considering a PERIOD3 polymorphism presumably impacting on sleep homeostasis. RESULTS: Our results link higher sleep-loss-related attentional vulnerability to cortical and subcortical deactivation patterns during slow reaction times (i.e., suboptimal vigilant attention). Concomitantly, thalamic regions were progressively less recruited with time-on-task and functionally less connected to task-related and arousal-promoting brain regions in those volunteers showing higher attentional instability in their behavior. The data further suggest that the latter is linked to shifts into a task-inactive default-mode network in between task-relevant stimulus occurrence. INTERPRETATION: We provide a multifaceted view on cerebral correlates of sleep loss at night and propose that genetic predisposition entails differential cerebral coping mechanisms, potentially compromising adequate performance during night work.


Assuntos
Nível de Alerta/genética , Atenção/fisiologia , Encéfalo/fisiopatologia , Ritmo Circadiano/genética , Proteínas Circadianas Period/genética , Tempo de Reação/genética , Privação do Sono/genética , Adulto , Nível de Alerta/fisiologia , Tronco Encefálico/fisiopatologia , Ritmo Circadiano/fisiologia , Feminino , Neuroimagem Funcional , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiopatologia , Polimorfismo Genético , Córtex Pré-Frontal/fisiopatologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Privação do Sono/fisiopatologia , Privação do Sono/psicologia , Tálamo/fisiopatologia , Adulto Jovem
16.
Front Behav Neurosci ; 8: 59, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24639634

RESUMO

Under sleep loss, vigilance is reduced and attentional failures emerge progressively. It becomes difficult to maintain stable performance over time, leading to growing performance variability (i.e., state instability) in an individual and among subjects. Task duration plays a major role in the maintenance of stable vigilance levels, such that the longer the task, the more likely state instability will be observed. Vulnerability to sleep-loss-dependent performance decrements is highly individual and is also modulated by a polymorphism in the human clock gene PERIOD3 (PER3). By combining two different protocols, we manipulated sleep-wake history by once extending wakefulness for 40 h (high sleep pressure condition) and once by imposing a short sleep-wake cycle by alternating 160 min of wakefulness and 80 min naps (low sleep pressure condition) in a within-subject design. We observed that homozygous carriers of the long repeat allele of PER3 (PER3 (5/5) ) experienced a greater time-on-task dependent performance decrement (i.e., a steeper increase in the number of lapses) in the Psychomotor Vigilance Task compared to the carriers of the short repeat allele (PER3 (4/4) ). These genotype-dependent effects disappeared under low sleep pressure conditions, and neither motivation, nor perceived effort accounted for these differences. Our data thus suggest that greater sleep-loss related attentional vulnerability based on the PER3 polymorphism is mirrored by a greater state instability under extended wakefulness in the short compared to the long allele carriers. Our results undermine the importance of time-on-task related aspects when investigating inter-individual differences in sleep loss-induced behavioral vulnerability.

17.
J Sleep Res ; 22(5): 573-80, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23509952

RESUMO

Light in the short wavelength range (blue light: 446-483 nm) elicits direct effects on human melatonin secretion, alertness and cognitive performance via non-image-forming photoreceptors. However, the impact of blue-enriched polychromatic light on human sleep architecture and sleep electroencephalographic activity remains fairly unknown. In this study we investigated sleep structure and sleep electroencephalographic characteristics of 30 healthy young participants (16 men, 14 women; age range 20-31 years) following 2 h of evening light exposure to polychromatic light at 6500 K, 2500 K and 3000 K. Sleep structure across the first three non-rapid eye movement non-rapid eye movement - rapid eye movement sleep cycles did not differ significantly with respect to the light conditions. All-night non-rapid eye movement sleep electroencephalographic power density indicated that exposure to light at 6500 K resulted in a tendency for less frontal non-rapid eye movement electroencephalographic power density, compared to light at 2500 K and 3000 K. The dynamics of non-rapid eye movement electroencephalographic slow wave activity (2.0-4.0 Hz), a functional index of homeostatic sleep pressure, were such that slow wave activity was reduced significantly during the first sleep cycle after light at 6500 K compared to light at 2500 K and 3000 K, particularly in the frontal derivation. Our data suggest that exposure to blue-enriched polychromatic light at relatively low room light levels impacts upon homeostatic sleep regulation, as indexed by reduction in frontal slow wave activity during the first non-rapid eye movement episode.


Assuntos
Luz , Sono/fisiologia , Sono/efeitos da radiação , Adulto , Atenção/fisiologia , Atenção/efeitos da radiação , Cor , Estudos Cross-Over , Eletroencefalografia , Feminino , Voluntários Saudáveis , Homeostase/efeitos da radiação , Humanos , Masculino , Melatonina/metabolismo , Fases do Sono/fisiologia , Fases do Sono/efeitos da radiação , Adulto Jovem
18.
Front Neurosci ; 5: 107, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21991243

RESUMO

BESIDES THE MASSIVE PLASTICITY AT THE LEVEL OF SYNAPSES, WE FIND IN THE HIPPOCAMPUS OF ADULT MICE AND RATS TWO SYSTEMS WITH VERY STRONG MACROSCOPIC STRUCTURAL PLASTICITY: adult neurogenesis, that is the lifelong generation of new granule cells, and dynamic changes in the mossy fibers linking the dentate gyrus to area CA3. In particular the anatomy of the infrapyramidal mossy fiber tract (IMF) changes in response to a variety of extrinsic and intrinsic stimuli. Because mossy fibers are the axons of granule cells, the question arises whether these two types of plasticity are linked. Using immunohistochemistry for markers associated with axonal growth and pro-opiomelanocortin (POMC)-GFP mice to visualize the post-mitotic maturation phase of adult hippocampal neurogenesis, we found that newly generated mossy fibers preferentially but not exclusively contribute to the IMF. The neurogenic stimulus of an enriched environment increased the volume of the IMF. In addition, the IMF grew with a time course consistent with axonal outgrowth from the newborn neurons after the induction of neurogenic seizures using kainate. These results indicate that two aspects of plasticity in the adult hippocampus, mossy fiber size and neurogenesis, are related and may share underlying mechanisms. In a second part of this study, published separately (Krebs et al., 2011) we have addressed the question of whether there is a shared genetics underlying both traits.

19.
Front Neurosci ; 5: 106, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21960957

RESUMO

The hippocampus of adult rodents harbors two systems exhibiting structural plasticity beyond the level of synapses and dendrites. First, the persistent generation of granule cells (adult neurogenesis); second, dynamic changes in the mossy fibers (MF), in particular in the infrapyramidal mossy fiber (IMF) tract. Because MFs are the axons of granule cells, the question arises whether these two types of plasticity are linked. In the first part of this study (Römer et al., 2011) we have asked how both traits are regulated in relation to each other. In the present part, we asked whether, besides activity-dependent co-regulation, there would also be signs of genetic co-regulation and co-variance. For this purpose we used the BXD panel of recombinant inbred strains of mice, a unique genetic reference population that allows genetic association studies. In 31 BXD strains we did not find correlations between the traits describing the volume of the MF subfields and measures of adult neurogenesis. When we carried out quantitative trait locus mapping for these traits, we found that the map for IMF volume showed little overlap with the maps for the other parts of the projection or for adult neurogenesis, suggesting that to a large degree the IMF is regulated independently. The highest overlapping peak in the genome-wide association maps for IMF volume and the number of new neurons was on distal chromosome 5 (118.3-199.2 Mb) with an LRS score of 5.5 for IMF and 6.0 for new neurons. Within this interval we identified Nos1 (neuronal nitric oxide synthase) as a cis-acting (i.e., presumably autoregulatory) candidate gene. The expression of Nos1 is has been previously linked with both IMF and adult neurogenesis, supporting our findings. Despite explaining on its own very little of the variance in the highly multigenic traits studied, our results suggest Nos1 may play a part in the complex genetic control of adult neurogenesis and IMF morphology.

20.
J Autism Dev Disord ; 41(6): 796-804, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20839043

RESUMO

The current study investigated if deficits in processing emotional expression affect facial identity processing and vice versa in children with autism spectrum disorder. Children with autism and IQ and age matched typically developing children classified faces either by emotional expression, thereby ignoring facial identity or by facial identity disregarding emotional expression. Typically developing children processed facial identity independently from facial expressions but processed facial expressions in interaction with identity. Children with autism processed both facial expression and identity independently of each other. They selectively directed their attention to one facial parameter despite variations in the other. Results indicate that there is no interaction in processing facial identity and emotional expression in autism spectrum disorder.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/psicologia , Emoções , Face , Expressão Facial , Reconhecimento Fisiológico de Modelo , Adolescente , Estudos de Casos e Controles , Criança , Humanos , Masculino , Testes Neuropsicológicos
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