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Decorative pictures (DP) are often used in multimedia task materials and are commonly considered so-called seductive details as they are commonly not task-relevant. Typically, DP result in mixed effects on behavioral performance measures. The current study focused on the effects of DP on the cognitive load during text reading and working memory task performance. The theta and alpha frequency band power of the electroencephalogram (EEG) and pupil dilation served as proxies of cognitive load. The number of fixations, mean fixation durations, and the number of transitions served as proxies of the attentional focus. For both, text reading and n-back working memory tasks, the presence and congruency of DP were manipulated in four task conditions. DP did neither affect behavioral performance nor subjective ratings of emotional-motivational factors. However, in both tasks, DP increased the cognitive load as revealed by the EEG alpha frequency band power and (at least to some extent) by subjective effort ratings. Notably, the EEG alpha frequency band power was a quite reliable and sensitive proxy of cognitive load. Analyzing the EEG data stimulus-locked and fixation-related, the EEG alpha frequency band power revealed a difference in global and local cognitive load. In sum, the current study underlines the feasibility and use of EEG for multimedia research, especially when combined with eye-tracking.
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Atenção , Eletroencefalografia , Tecnologia de Rastreamento Ocular , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/fisiologia , Masculino , Feminino , Adulto Jovem , Adulto , Atenção/fisiologia , Leitura , Cognição/fisiologia , Aprendizagem/fisiologia , Ritmo alfa/fisiologiaRESUMO
Introduction: The use of medical cannabis in pediatrics is not common in clinical practice, and there is a lack of prospective studies, especially in pediatric subpopulations. This study aimed to provide data on the off-label administration of tetrahydrocannabinol (∆9-THC) in a pediatric tertiary center in Austria. Methods: A retrospective data analysis was performed to assess the use of ∆9-THC at the Department of Pediatrics and Adolescent Medicine at the Comprehensive Center of Pediatrics (Medical University Vienna) from 2016 to 2018. The use of ∆9-THC in the Pediatric Department at the Medical University Vienna between 2016 and 2018 was analyzed using a retrospective design. Results: The most common diagnoses of patients receiving ∆9-THC were brain cancer and genetic diseases, including inborn metabolic disorders. The 32 patients who had received ∆9-THC had an arithmetic mean of 9.42 diagnoses and were treated with an arithmetic mean of 13.52 other drugs. Eleven of the 32 patients died by the end of the study period, indicating palliative use. Conclusion: The data shows that only severely ill patients were treated with ∆9-THC. A lack of information on the drug's indications, duration, and dosage was noticed in the files, which could represent problems for patient safety.
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Gamification of cognitive tasks might positively affect emotional-motivational factors (emotional design perspective) or negatively affect cognitive factors like working memory load (minimalistic design perspective). The current study examined the effects of gamification in a spatial n-back working memory task on task performance, task load (i.e., working memory load and effort), and subjective task experience. Task load was assessed by the physiological process measures pupil dilation and EEG theta (4-6 Hz) and alpha (8-13 Hz) frequency band power. Gamification was achieved by elements of emotional design (i.e., the visual screen design using, e.g., color, cartoon figures as n-back stimuli, and a narrative embedding of the task). While EEG and eye-tracking were recorded, participants conducted gamified and non-gamified 1-back and 2-back load levels. The gamification resulted in positive effects on subjective task experience and affect. Despite these effects, gamification did not affect task performance and task load. However, exploratory analyses revealed increased EEG theta power at right-parietal electrodes for gamified task versions compared to non-gamified ones. Potentially, this effect might indicate participants' increased effort or concentration in the gamified n-back task. In line with an emotional design perspective, gamification positively altered subjective task experience and affect without hampering task performance and therefore justify the extra effort of implementing game elements.
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Eletroencefalografia , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/fisiologia , Eletroencefalografia/métodos , Gamificação , Tecnologia de Rastreamento Ocular , MotivaçãoRESUMO
Although self-injurious thoughts and behaviors are a global health concern, little is known about suicidal threat/gesture(s) where a person leads others to believe they want to end their lives when they have no intention to do so. This study assessed the lifetime prevalence of self-injurious thoughts and behaviors among both community adolescents (n = 1117) and in clinical youth (n = 191). Suicide threats/gestures were common among youth; 12.2% of community adolescents and 18.0% of clinical youth reporting having made a suicide threat/gesture, most commonly in the context of other self-injurious thoughts and behaviors. Across both samples, suicide threats/gestures were not uniquely associated with suicide attempts, and youth who reported suicide threats/gestures in the context of a history of self-harm or suicide plan(s) were no more likely to report a history of suicide attempt(s). Suicide threats/gestures were distinguished from suicide attempts in that they primarily fulfilled positive social functions, rather than autonomic functions. Findings suggest that suicidal threats/gestures are common in both community and clinical youth, and are not uniquely associated with suicide attempts, but rather function to communicate distress to others.
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Comportamento Autodestrutivo , Tentativa de Suicídio , Humanos , Adolescente , Gestos , Ideação Suicida , Comportamento Autodestrutivo/epidemiologia , Prevalência , Fatores de RiscoRESUMO
Across two experiments, the effects of presenting decorative pictures (DP) alongside texts were assessed with respect to the mental processing demands during reading, learning outcomes, and subjective task experience. DP were thought to function as so-called seductive details. Eye-tracking and the electroencephalogram (EEG) were recorded during reading. Pupil dilation and the EEG theta (4-8 Hz) and alpha (8-13 Hz) frequency band power served as measures of the mental processing demands. Texts on features and habitats of animals served as learning materials. Working memory (WM) load was manipulated as an additional factor during reading. Neither the additional WM load nor DP had significant effects on learning outcomes, albeit in both experiments the increased WM load affected the physiological measures as expected. DP with a few different motifs generally were not very seductive (Experiment 1). DP with more diverse motifs resulted in increased mental processing demands as indicated by the EEG alpha frequency band power (Experiment 2). Subjective task experience was positively affected by the DP present in Experiment 2 as indicated by higher subjective ratings of interestingness, comprehensibility, emotionality, and aesthetical pleasantness when DP were present. In sum, the study indicates that DP with diverse motifs may function as seductive details, increasing mental processing demands without detrimental effects on learning outcomes.
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Eletroencefalografia , Tecnologia de Rastreamento Ocular , Humanos , Eletroencefalografia/métodos , Memória de Curto Prazo/fisiologia , LeituraRESUMO
BACKGROUND: The COVID-19 pandemic results in disproportional consequences for psychiatric patients. Due to restraints in physical contacts, providers switched from face-to-face contacts to teletherapy, but prior experiences were mostly limited. The study aimed at assessing symptom dynamics, potentially increased adversities and factors influencing a successful transition into teletherapy in adolescent psychiatric outpatients during the COVID-19 pandemic. METHOD: Thirty adolescent psychiatric outpatients participated in an interview-based study. The differential impact of the COVID-19 pandemic was measured by integrating patients' and psychiatrists' judgements. RESULTS: Patients who reported deteriorated symptoms and patients who showed (partial) improvement of symptomatology could be separated by feelings of isolation (specific to deterioration) and perceived reduction in school-associated stress (unique to improvement). Patients with worsening symptomatology showed a significantly higher degree of psychosocial disability before lockdown and at the first interview. Patients who deteriorated in their level of psychosocial functioning also reported negatively on teletherapy. These patients were verbally less differentiated concerning emotions and affect, reported introspection and rumination, and stated distinctly lower levels of perceived social support. Concerning adversities, no clear trend could be identified, but some patients reported increased domestic violence and neglect. CONCLUSIONS: Patients with a higher degree of psychosocial disability suffer disproportionally from the crisis, so that an assessment of functioning should serve as a triage tool. Also, a screening of the perceived level of social support should be established before offering teletherapy. Additionally, the provision of strategies to enhance verbalisation and differentiation of emotions and affect might be beneficial.
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COVID-19 , Adolescente , Controle de Doenças Transmissíveis , Humanos , Pacientes Ambulatoriais , Pandemias/prevenção & controle , SARS-CoV-2RESUMO
Using and combining eye-tracking and EEG frequency band power as process measures, in the current study we were interested in the mental processing demands during learning of text-picture combinations that either enabled or prohibited text-picture integration (TPI). In the mismatch condition, the textual and pictorial information being dissimilar, TPI was not possible, whereas in the match and the partial-match condition, the textual and pictorial information being identical respective complementary, TPI was possible. We expected mental processing demands to be higher in the mismatch condition, when pictorial and textual information had to be processed and memorized as separate representations, compared to the match and partial-match conditions when TPI was possible. As expected, on virtually all process measures we observed increased mental processing demands when two mental representations had to be processed and memorized compared to the two conditions where TPI was possible. The EEG alpha and theta frequency band power data corroborated and extended the eye-tracking measures of mental processing demands. In addition, we performed a fixation-related EEG frequency band power analysis that also corroborated the results of the classic stimulus-locked EEG frequency band power analysis, exemplifying the use of this former methodology in the context of complex multimedia task materials.
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Eletroencefalografia , Tecnologia de Rastreamento Ocular , Humanos , AprendizagemRESUMO
Given an indication for pharmacological treatment, prescribers can only draw from a rather limited number of substances with a label for the treatment of children and adolescents suffering from psychiatric disorders. In order to capture the currently available substances with such a label in Austria and to thus provide one element of informed patient education, the Austrian medicinal product index of the Austrian Federal Office for Safety in Health Care has been systematically searched. The resulting tables are being presented.
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Rotulagem de Medicamentos/legislação & jurisprudência , Transtornos Mentais/tratamento farmacológico , Psicotrópicos/uso terapêutico , Adolescente , Áustria , Criança , HumanosRESUMO
OBJECTIVE: According to current theoretical models of working memory (WM), executive functions (EFs) like updating, inhibition and shifting play an important role in WM functioning. The models state that EFs highly correlate with each other but also have some individual variance which makes them separable processes. Since this theory has mostly been substantiated with behavioral data like reaction time and the ability to execute a task correctly, the aim of this paper is to find evidence for diversity (unique properties) of the EFs updating and inhibition in neural correlates of EEG data by means of using brain-computer interface (BCI) methods as a research tool. To highlight the benefit of this approach we compare this new methodology to classical analysis approaches. METHODS: An existing study has been reinvestigated by applying neurophysiological analysis in combination with support vector machine (SVM) classification on recorded electroencephalography (EEG) data to determine the separability and variety of the two EFs updating and inhibition on a single trial basis. RESULTS: The SVM weights reveal a set of distinct features as well as a set of shared features for the two EFs updating and inhibition in the theta and the alpha band power. SIGNIFICANCE: In this paper we find evidence that correlates for unity and diversity of EFs can be found in neurophysiological data. Machine learning approaches reveal shared but also distinct properties for the EFs. This study shows that using methods from brain-computer interface (BCI) research, like machine learning, as a tool for the validation of psychological models and theoretical constructs is a new approach that is highly versatile and could lead to many new insights.
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Córtex Cerebral/fisiologia , Eletroencefalografia , Função Executiva/fisiologia , Inibição Psicológica , Memória de Curto Prazo/fisiologia , Desempenho Psicomotor/fisiologia , Máquina de Vetores de Suporte , Adulto , Feminino , Humanos , Masculino , Adulto JovemRESUMO
According to theoretical accounts, both, N-back and complex span tasks mainly require working memory (WM) processing. In contrast, simple span tasks conceptually mainly require WM storage. Thus, conceptually, an N-back task and a complex span task share more commonalities as compared to a simple span task. In the current study, we compared an N-back task, a complex operation span task (Ospan), and a simple digit span task (Dspan) by means of typical WM load-related measures of the Electroencephalogram (EEG) like the parietal alpha and beta frequency band power, the frontal theta frequency band power, and the P300 amplitude, to examine whether these tasks would show commonalities or differences in WM processing-load. We expected that increasing WM-load would generally lead to a decreased alpha and beta frequency band power, an increased theta frequency band power, and a decreased P300 amplitude. Yet, based on the conceptual considerations, we hypothesized that the outcomes of these measures would be more comparable between the N-back and the Ospan as compared to the Dspan. Our hypotheses were partly confirmed. The N-back and the Ospan showed timely more prolonged alpha frequency band power effects as compared to the Dspan. This might indicate higher demands on WM processing in the former two tasks. The theta frequency band power and the P300 amplitude were most pronounced in the N-back task as compared to both span tasks. This might indicate specific demands on cognitive control in the N-back task. Additionally, we observed that behavioral performance measures correlated with changes in EEG alpha power of the N-back and the Ospan, yet not of the Dspan. Taken together, the hypothesized conceptual commonalities between the N-back task and the Ospan (and, for the Dspan, differences) were only partly confirmed by the electrophysiological WM load-related measures, indicating a potential need for reconsidering the theoretical accounts on WM tasks and the value of a closer link to electrophysiological research herein.
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Most brain-based measures of the electroencephalogram (EEG) are used in highly controlled lab environments and only focus on narrow mental states (e.g., working memory load). However, we assume that outside the lab complex multidimensional mental states are evoked. This could potentially create interference between EEG signatures used for identification of specific mental states. In this study, we aimed to investigate more realistic conditions and therefore induced a combination of working memory load and affective valence to reveal potential interferences in EEG measures. To induce changes in working memory load and affective valence, we used a paradigm which combines an N-back task (for working memory load manipulation) with a standard method to induce affect (affective pictures taken from the International Affective Picture System (IAPS) database). Subjective ratings showed that the experimental task was successful in inducing working memory load as well as affective valence. Additionally, performance measures were analyzed and it was found that behavioral performance decreased with increasing workload as well as negative valence, showing that affective valence can have an effect on cognitive processing. These findings are supported by changes in frontal theta and parietal alpha power, parameters used for measuring of working memory load in the EEG. However, these EEG measures are influenced by the negative valence condition as well and thereby show that detection of working memory load is sensitive to affective contexts. Unexpectedly, we did not find any effects for EEG measures typically used for affective valence detection (Frontal Alpha Asymmetry (FAA)). Therefore we assume that the FAA measure might not be usable if cognitive workload is induced simultaneously. We conclude that future studies should account for potential context-specifity of EEG measures.
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Prefrontal dopamine levels are relatively increased in adolescence compared to adulthood. Genetic variation of COMT (COMT Val158Met) results in lower enzymatic activity and higher dopamine availability in Met carriers. Given the dramatic changes of synaptic dopamine during adolescence, it has been suggested that effects of COMT Val158Met genotypes might have oppositional effects in adolescents and adults. The present study aims to identify such oppositional COMT Val158Met effects in adolescents and adults in prefrontal brain networks at rest. Resting state functional connectivity data were collected from cross-sectional and multicenter study sites involving 106 healthy young adults (mean age 24 ± 2.6 years), gender matched to 106 randomly chosen 14-year-olds. We selected the anterior medial prefrontal cortex (amPFC) as seed due to its important role as nexus of the executive control and default mode network. We observed a significant age-dependent reversal of COMT Val158Met effects on resting state functional connectivity between amPFC and ventrolateral as well as dorsolateral prefrontal cortex, and parahippocampal gyrus. Val homozygous adults exhibited increased and adolescents decreased connectivity compared to Met homozygotes for all reported regions. Network analyses underscored the importance of the parahippocampal gyrus as mediator of observed effects. Results of this study demonstrate that adolescent and adult resting state networks are dose-dependently and diametrically affected by COMT genotypes following a hypothetical model of dopamine function that follows an inverted U-shaped curve. This study might provide cues for the understanding of disease onset or dopaminergic treatment mechanisms in major neuropsychiatric disorders such as schizophrenia and attention deficit hyperactivity disorder.
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Catecol O-Metiltransferase/genética , Catecol O-Metiltransferase/fisiologia , Polimorfismo de Nucleotídeo Único , Córtex Pré-Frontal/fisiologia , Adolescente , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Estudos Transversais , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Adulto JovemRESUMO
We investigated the interplay between inhibition and updating, two executive working memory (WM) functions. We applied a novel task paradigm consisting of flanker stimuli presented within an n-back task and studied the interaction between inhibitory demands and load on WM updating using behavioral measures, EEG, and pupil dilation. In contrast to studies that examine the interaction between inhibitory demands and load on WM storage components, the current task paradigm allowed testing the interaction between the executive WM components updating and inhibition. We found a reduced flanker interference effect for the highest (2-back) updating load condition compared to lower updating load conditions on most measures. We interpret these findings as indicating that inhibitory control and WM updating are closely intertwined executive functions. Increased load on updating seemed to result in an overall more activated attentional network thus enhancing inhibitory control, such that task performance is less susceptible to distracting information.
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Encéfalo/fisiologia , Função Executiva/fisiologia , Inibição Psicológica , Memória de Curto Prazo/fisiologia , Pupila/fisiologia , Adulto , Atenção/fisiologia , Dilatação , Eletroencefalografia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto JovemRESUMO
Executive working memory functions play a central role in reading comprehension. In the present research we were interested in additional load imposed on executive functions by link-selection processes during computer-based reading. For obtaining process measures, we used a methodology of concurrent electroencephalographic (EEG) and eye-tracking data recording that allowed us to compare epochs of pure text reading with epochs of hyperlink-like selection processes in an online reading situation. Furthermore, this methodology allowed us to directly compare the two physiological load-measures EEG alpha frequency band power and pupil dilation. We observed increased load on executive functions during hyperlink-like selection processes on both measures in terms of decreased alpha frequency band power and increased pupil dilation. Surprisingly however, the two measures did not correlate. Two additional experiments were conducted that excluded potential perceptual, motor, or structural confounds. In sum, EEG alpha frequency band power and pupil dilation both turned out to be sensitive measures for increased load during hyperlink-like selection processes in online text reading.
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Ondas Encefálicas/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Hipermídia , Pupila/fisiologia , Adulto , Compreensão/fisiologia , Eletroencefalografia , Feminino , Humanos , Masculino , Memória de Curto Prazo , Leitura , Adulto JovemRESUMO
Insufficient default mode network (DMN) suppression was linked to increased rumination in symptomatic Major Depressive Disorder (MDD). Since rumination is known to predict relapse and a more severe course of MDD, we hypothesized that similar DMN alterations might also exist during full remission of MDD (rMDD), a condition known to be associated with increased relapse rates specifically in patients with adolescent onset. Within a cross-sectional functional magnetic resonance imaging study activation and functional connectivity (FC) were investigated in 120 adults comprising 78 drug-free rMDD patients with adolescent- (n = 42) and adult-onset (n = 36) as well as 42 healthy controls (HC), while performing the n-back task. Compared to HC, rMDD patients showed diminished DMN deactivation with strongest differences in the anterior-medial prefrontal cortex (amPFC), which was further linked to increased rumination response style. On a brain systems level, rMDD patients showed an increased FC between the amPFC and the dorsolateral prefrontal cortex, which constitutes a key region of the antagonistic working-memory network. Both whole-brain analyses revealed significant differences between adolescent-onset rMDD patients and HC, while adult-onset rMDD patients showed no significant effects. Results of this study demonstrate that reduced DMN suppression exists even after full recovery of depressive symptoms, which appears to be specifically pronounced in adolescent-onset MDD patients. Our results encourage the investigation of DMN suppression as a putative predictor of relapse in clinical trials, which might eventually lead to important implications for antidepressant maintenance treatment.
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Córtex Cerebral/patologia , Transtorno Depressivo Maior/complicações , Transtornos da Memória/etiologia , Memória de Curto Prazo/fisiologia , Vias Neurais/patologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Escalas de Graduação Psiquiátrica , Adulto JovemRESUMO
Hippocampal volume loss has been related to chronic stress as well as genetic factors. Although genetic and environmental variables affecting hippocampal volume have extensively been studied and related to mental illness, limited evidence is available with respect to G × E interactions on hippocampal volume. The present MRI study investigated interaction effects on hippocampal volume between three well-studied functional genetic variants (COMT Val158Met, BDNF Val66Met, 5-HTTLPR) associated with hippocampal volume and a measure of environmental adversity (life events questionnaire) in a large sample of healthy humans (n = 153). All three variants showed significant interactions with environmental adversity with respect to hippocampal volume. Observed effects were additive by nature and driven by both recent as well as early life events. A consecutive analysis of hippocampal subfields revealed a spatially distinct profile for each genetic variant suggesting a specific role of 5-HTTLPR for the subiculum, BDNF Val66Met for CA4/dentate gyrus, and COMT Val158Met for CA2/3 volume changes. The present study underscores the importance of G × E interactions as determinants of hippocampal volume, which is crucial for the neurobiological understanding of stress-related conditions, such as mood disorders or post-traumatic stress disorder (PTSD).
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Interação Gene-Ambiente , Nível de Saúde , Hipocampo/fisiologia , Acontecimentos que Mudam a Vida , Adolescente , Adulto , Feminino , Hipocampo/patologia , Humanos , Masculino , Tamanho do Órgão/fisiologia , Adulto JovemRESUMO
The vast majority of approved antidepressants and antipsychotics exhibit a complex pharmacology. The mechanistic understanding of how these psychotropic medications are related to adverse drug reactions (ADRs) is crucial for the development of novel drug candidates and patient adherence. This study aims to associate in vitro assessed binding affinity profiles (39 compounds, 24 molecular drug targets) and ADRs (n=22) reported in clinical trials of antidepressants and antipsychotics (n>59.000 patients) by the use of robust multivariate statistics. Orthogonal projection to latent structures (O-PLS) regression models with reasonable predictability were found for several frequent ADRs such as nausea, diarrhea, hypotension, dizziness, headache, insomnia, sedation, sleepiness, increased sweating, and weight gain. Results of the present study support many well-known pharmacological principles such as the association of hypotension and dizziness with α1-receptor or sedation with H1-receptor antagonism. Moreover, the analyses revealed novel or hardly investigated mechanisms for common ADRs including the potential involvement of 5-HT6-antagonism in weight gain, muscarinic receptor antagonism in dizziness, or 5-HT7-antagonism in sedation. To summarize, the presented study underlines the feasibility and value of a multivariate data mining approach in psychopharmacological development of antidepressants and antipsychotics.
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Antidepressivos/efeitos adversos , Antipsicóticos/efeitos adversos , Tontura/induzido quimicamente , Hipertensão/induzido quimicamente , Análise Multivariada , Ensaios Clínicos como Assunto/efeitos adversos , Ensaios Clínicos como Assunto/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Humanos , Técnicas In Vitro , Masculino , Ligação ProteicaRESUMO
BACKGROUND: The serotonin transporter (5-HTT) is abundantly expressed in humans by the serotonin transporter gene SLC6A4 and removes serotonin (5-HT) from extracellular space. A blood-brain relationship between platelet and synaptosomal 5-HT reuptake has been suggested, but it is unknown today, if platelet 5-HT uptake can predict neural activation of human brain networks that are known to be under serotonergic influence. METHODS: A functional magnetic resonance study was performed in 48 healthy subjects and maximal 5-HT uptake velocity (Vmax) was assessed in blood platelets. We used a mixed-effects multilevel analysis technique (MEMA) to test for linear relationships between whole-brain, blood-oxygen-level dependent (BOLD) activity and platelet Vmax. RESULTS: The present study demonstrates that increases in platelet Vmax significantly predict default-mode network (DMN) suppression in healthy subjects independent of genetic variation within SLC6A4. Furthermore, functional connectivity analyses indicate that platelet Vmax is related to global DMN activation and not intrinsic DMN connectivity. CONCLUSION: This study provides evidence that platelet Vmax predicts global DMN activation changes in healthy subjects. Given previous reports on platelet-synaptosomal Vmax coupling, results further suggest an important role of neuronal 5-HT reuptake in DMN regulation.
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Plaquetas/fisiologia , Encéfalo/fisiologia , Conectoma , Vias Neurais , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Serotonina/metabolismo , Adolescente , Adulto , Feminino , Neuroimagem Funcional , Variação Genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto JovemRESUMO
OBJECTIVES: To review neuroimaging intermediate phenotypes of MDD and their relation to genetic risk variants. METHODS: A systematic literature search of peer-reviewed English language articels using PubMed ( www.pubmed.org ) was performed. RESULTS: Comprehensive evidence on the influence of serotonergic genes (SLC6A4, HTR1A, MAOA, TPH2) and BDNF on the following neural intermediate phenotypes is displayed: amygdala reactivity, coupling of amygdala-anterior cingulate cortex (ACC) activity, ACC volume, hippocampal volume and serotonin receptor 1A (5-HT1A) binding potential (BP). CONCLUSIONS: Intermediate phenotypes may bridge the gap between genotype and phenotype by reducing the impreciseness of psychiatric phenotypes and yield more insights into the underlying biology.