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1.
Nervenarzt ; 95(1): 18-27, 2024 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-38110535

RESUMO

BACKGROUND: In Germany different offers of social support are available for families that are provided by different sectors, e.g., the youth welfare and the healthcare systems. OBJECTIVE: Documentation of the utilized help, child-related factors that are associated with the utilization and the parental desires for support. MATERIAL AND METHODS: Survey of 160 parents undergoing (partial) inpatient treatment in psychiatric hospitals via an oral interview using standardized and semi-standardized instruments. RESULTS: The results show that nonprofessional help by family and friends as well as support offers provided by the healthcare system are used most frequently. Families that perceived their children as more burdened receive more help than families with children judged as being less burdened. There are regional differences especially in the utilization of high-threshold help by the healthcare system. DISCUSSION: Support offers seem to reach families with mental illnesses, especially those that are particularly burdened; however, there are regional differences regarding the utilization of support as well as the wishes for specific support offers.


Assuntos
Filho de Pais com Deficiência , Transtornos Mentais , Pessoas Mentalmente Doentes , Adolescente , Humanos , Pessoas Mentalmente Doentes/psicologia , Pais/psicologia , Transtornos Mentais/terapia , Família , Filho de Pais com Deficiência/psicologia
2.
Acta Psychiatr Scand ; 147(3): 267-275, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36585782

RESUMO

INTRODUCTION: Lithium augmentation (LA) of antidepressants is a first-line therapy option for treatment-resistant depression (TRD). Nevertheless, it is rarely used in geriatric patients mostly because of the fear of kidney toxicity. The purpose of this study is to investigate estimated glomerular filtration rate (eGFR) changes and number of acute kidney injuries (AKI) using LA in geriatric compared with non-geriatric patients. METHODS: In a prospective multicenter cohort study, eGFR changes were measured in 201 patients with unipolar depression (nage≥65years  = 29; nage<65years  = 172) at baseline and over 2-6 weeks of LA. We used linear mixed models to investigate changes in eGFR upon LA and assessed the number of AKIs, according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. RESULTS: Both age groups showed a significant eGFR decline over the course of treatment with lower eGFR in geriatric patients. The lithium serum level (interpretable as "effect of LA") had a significant effect on eGFR decline. Both effects (age group and lithium serum level) on eGFR decline did not influence each other, meaning the effect of LA on eGFR decline did not differ between age groups. Two AKIs were observed in the geriatric age group when serum lithium levels exceeded the therapeutic range of >0.8 mmol/L. CONCLUSION: This is the first study investigating eGFR change and AKI upon LA for TRD in geriatric compared with non-geriatric patients. Our data suggest that LA, as an effective treatment option in geriatric patients, should be closely monitored to avoid AKIs.


Assuntos
Injúria Renal Aguda , Transtorno Depressivo Resistente a Tratamento , Humanos , Idoso , Lítio/uso terapêutico , Depressão , Estudos de Coortes , Estudos Prospectivos , Rim , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico
3.
Pharmacopsychiatry ; 56(2): 57-63, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31370081

RESUMO

Schizophrenia is a complex, heterogeneous psychiatric disorder that affects about 1% of the global population. Hippocampal dysfunction has been linked to both cognitive deficits and positive symptoms in schizophrenia. Here, we briefly review current findings on disrupted hippocampal processing from a clinical perspective before concentrating on preclinical studies of aberrant hippocampal synaptic plasticity using the N-methyl-D-aspartate receptor hypofunction model of psychosis and related findings from genetic models. Taken together, the results put the case for maladaptive hippocampal synaptic plasticity and its extrinsic connections as mechanistic underpinnings of cognitive impairments in schizophrenia.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Animais , Hipocampo/metabolismo , Plasticidade Neuronal/fisiologia , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Roedores/metabolismo
4.
BMC Public Health ; 23(1): 232, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732703

RESUMO

BACKGROUND: The COVID-19 pandemic continues to spread across the globe and is associated with significant clinical and humanitarian burden. The desire for parenthood has been described to be positively correlated with psychological well-being: An unfulfilled wish for parenthood is associated with impaired mental health, and the wish for parenthood is a predictor for the development of depressive symptoms. While higher rates of anxiety and depression have been reported in individuals with minoritized sexual identities (compared to heterosexual individuals) during the COVID-19 pandemic, the specific impact of the pandemic and its social restriction measures on this population is poorly understood. METHODS: From April to July 2020, we conducted an anonymous cross-sectional survey online among N = 2463 adults living in Germany. We screened for depressive symptoms (Patient Health Questionnaire-4; PHQ-4) and assessed individuals' desire for parenthood during the pandemic, and motives for or against the desire for parenthood (Leipzig questionnaire on motives for having a child, Version 20; LKM-20), with the aim of identifying differences between individuals with minoritized sexual identities and heterosexual individuals. RESULTS: Compared to heterosexual individuals (n = 1304), individuals with minoritized sexual identities (n = 831) indicated higher levels of depressive symptoms. In our study sample the majority of all participants (81.9%) reported no change in the desire for parenthood since the COVID-19 pandemic. CONCLUSION: The findings underline the unmet need for social, psychological and medical support in regard to family-planning and the desire for parenthood during a pandemic. Furthermore, future research should explore COVID-19-related psychological consequences on individuals' desire for parenthood and building a family.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Serviços de Planejamento Familiar , Pandemias
5.
J Clin Psychopharmacol ; 42(1): 87-91, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34854829

RESUMO

PURPOSE/BACKGROUND: Lithium augmentation of antidepressants represents a common strategy to overcome treatment resistance in patients with major depressive disorder. The use of lithium has been associated with cardiovascular adverse effects such as QTc prolongation and tachyarrhythmia. Although the previous studies investigated monotherapy with lithium, the aim of this study was to investigate electrocardiographic changes in LA. METHODS/PROCEDURES: A 12-lead surface electrocardiogram (ECG) was obtained from 38 patients with major depressive disorder before and during LA. Changes in heart rate, PQ, QRS and QTc interval, QT dispersion, ST segment, and T- and U-wave alterations were analyzed using a linear mixed model. FINDINGS/RESULTS: The ECG readings of 33 patients were evaluated. Lithium augmentation was not significantly associated with changes in heart rate, QTc, PQ, or QRS interval. We found a significant decrease in QT dispersion. These results were independent of sex, age, stable comedication, and comorbidities. During LA, we observed 9 cases of T-wave alterations and 2 cases of new U waves. CONCLUSIONS: Our data provide no evidence for serious ECG abnormalities at therapeutic serum lithium levels in patients treated with LA. In particular, we did not find evidence for QTc time lengthening or tachyarrhythmia, such as torsades des pointes. The recommended intervals for ECG checks should be considered to detect long-term effects of LA.


Assuntos
Antidepressivos/efeitos adversos , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Cardiopatias/induzido quimicamente , Compostos de Lítio/efeitos adversos , Adulto , Antidepressivos/administração & dosagem , Antidepressivos/sangue , Sinergismo Farmacológico , Quimioterapia Combinada , Eletrocardiografia , Feminino , Humanos , Compostos de Lítio/administração & dosagem , Compostos de Lítio/sangue , Masculino , Pessoa de Meia-Idade
6.
J Sex Med ; 19(6): 907-922, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35370105

RESUMO

BACKGROUND: Preliminary research shows a substantial impact of the COVID-19 pandemic on women's sexual health, whereby empirical work on sexual well-being of minoritized sexual identities is still rare. AIM: The objective of this study was to explore sexual health in heterosexual, lesbian and bisexual cis women during the first wave of COVID-19 pandemic in Germany. METHODS: An anonymous nationwide online survey was conducted among cis women during the first nationwide lockdown in Germany from April 20th to July 20th, 2020. The questionnaire was distributed via e-mail, online chats and social-media platforms. OUTCOMES: Demographic variables and self-report measures from the Sexual Behavior Questionnaire (SBQ-G) "before the pandemic" and "since the pandemic" were collected. RESULTS: A total of 1,368 cis women participants were included: heterosexual women (n = 844), lesbian women (n = 293), bisexual women (n = 231). Results indicate overall decrease in frequency of sexual contacts and masturbation during the COVID-19 pandemic. Regarding differences before and during the pandemic lesbian women showed significant changes in sexual arousal whereas heterosexual women showed significant changes in all dimensions except capability to enjoy sexual intercourse. The data of bisexual women showed significant changes in almost all dimensions except for frequency of sexual intercourse and sexual arousal. Results of the multiple regression analysis revealed that being younger than 36 years-old, and being in a relationship as well as being heterosexual (compared with being lesbian) is positively associated with general satisfaction with sexual life during the pandemic. CLINICAL IMPLICATIONS: The findings suggest that during a pandemic sexual and mental health care for (cis) women should be provided and address the specific needs of sexual minority groups. STRENGTHS & LIMITATIONS: This is the first study to describe sexual behavior in heterosexual, lesbian and bisexual women during the COVID-19 pandemic in Germany. Limitations, however, include the fact that the data described were obtained at only one time point so there is a possibility of recall bias, and that the results cannot be generalized because of the underrepresentation of women over age 46. CONCLUSION: This study examined the impact of the COVID-19 pandemic and resulting social constraints on the sexual health of particular groups of lesbian and bisexual women, which may improve preparedness for future public health and policy crises. Batz F, Lermer E, Hatzler L, et al. The Impact of the COVID-19 Pandemic on Sexual Health in Cis Women Living in Germany. J Sex Med 2022;19:907-922.


Assuntos
COVID-19 , Saúde Sexual , Minorias Sexuais e de Gênero , Adulto , Bissexualidade/psicologia , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Feminino , Alemanha/epidemiologia , Humanos , Pessoa de Meia-Idade , Pandemias , Comportamento Sexual
7.
Neuropsychobiology ; 81(1): 69-79, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515179

RESUMO

INTRODUCTION: Asymmetrical alpha and frontal theta activity have been discussed as neurobiological markers for antidepressant treatment response. While most studies focus on resting-state EEG, there is evidence that task-related activity assessed at multiple time points might be superior in detecting subtle early differences. METHODS: This was a naturalistic study design assessing participants in a psychiatric in- and outpatient hospital setting. We investigated stimulus-related EEG asymmetry (frontal and occipital alpha-1 and alpha-2) and power (frontal midline theta) assessed at baseline and 1 week after initiation of pharmacological depression treatment while presenting affective stimuli. We then compared week 4 responders and nonresponders to antidepressant treatment. RESULTS: Follow-up analyses of a significant group × emotion × time interaction (p < 0.04) for alpha-1 asymmetry showed that responders differed significantly at baseline in their asymmetry scores in response to sad compared to happy faces with a change in this pattern 1 week later. Nonresponders did not show this pattern. No significant results were found for alpha-2, occipital alpha-1, and occipital alpha-2 asymmetry or frontal midline theta power. DISCUSSION: Our study addresses the gap in comparisons of task-related EEG activity changes measured at two time points and supports the potential value of this approach in detecting early differences in responders versus nonresponders to pharmacological treatment. Important limitations include the small sample size and the noncontrolled study design.


Assuntos
Antidepressivos , Eletroencefalografia , Antidepressivos/uso terapêutico , Encéfalo , Emoções , Humanos
8.
BMC Health Serv Res ; 22(1): 1279, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36280876

RESUMO

BACKGROUND: Depression is the most common mental health burden worldwide. Primary care physicians (PCPs) play a key role in the care provision for people with depression. The first objective of the present study was to examine the health care situation of depression in primary care, focusing on the cooperation between PCPs and mental health specialists. Secondly, we aimed at examining the role of the German S3 Guideline for Unipolar Depression in the primary care provision. METHODS: Data of N = 75 PCPs were analysed from a cross-sectional online survey. Analysis of descriptive information on the current status of primary health care and depression was conducted. Further, to examine factors that are related to the usage of guidelines, multiple regression was performed. RESULTS: Only 22.1% of PCPs described the quality of cooperation with ambulatory mental health specialist as good. The most frequent problems in the cooperation were of structural nature (49.3%, long waiting list, few therapy units, as well as barriers in the communication and the information exchange). With regard to the role of the guideline, 65% of PCPs reported never or seldom using the guideline and 31.7% of PCPs perceived the guideline as not useful at all. In addition, perceived usefulness of the S3 guideline was positively associated with the usage of the guideline. Results of the logistic regression revealed a significant association between the usage of the German S3 Guideline for Unipolar Depression and rating of perceived usefulness of the guideline (OR: 4.771; 95% CI: 2.15-10.59; p < 0.001). CONCLUSION: This study highlights the central role of PCPs and demonstrates major barriers in the outpatient health care provision of depression. Present findings suggest a strong need for collaborative health care models to resolve obstacles resulting from fragmented mental health care systems. Finally, reported perceived barriers in the implementation of the German S3 Guideline for Unipolar Depression indicate the urge to involve PCPs in the development of evidence-based guidelines, in order to ensure a successful implementation and usage of guidelines in clinical practice.


Assuntos
Médicos de Atenção Primária , Humanos , Estudos Transversais , Depressão/epidemiologia , Depressão/terapia , Alemanha , Atenção Primária à Saúde
9.
Eur J Neurosci ; 53(12): 3942-3959, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32583466

RESUMO

Alterations of the brain extracellular matrix (ECM) can perturb the structure and function of brain networks like the hippocampus, a key region in human memory that is commonly affected in psychiatric disorders. Here, we investigated the potential effects of a genome-wide psychiatric risk variant in the NCAN gene encoding the ECM proteoglycan neurocan (rs1064395) on memory performance, hippocampal function and cortical morphology in young, healthy volunteers. We assessed verbal memory performance in two cohorts (N = 572, 302) and found reduced recall performance in risk allele (A) carriers across both cohorts. In 117 participants, we performed functional magnetic resonance imaging using a novelty-encoding task with visual scenes. Risk allele carriers showed higher false alarm rates during recognition, accompanied by inefficiently increased left hippocampal activation. To assess effects of rs1064395 on brain morphology, we performed voxel-based morphometry in 420 participants from four independent cohorts and found lower grey matter density in the ventrolateral and rostral prefrontal cortex of risk allele carriers. In silico eQTL analysis revealed that rs1064395 SNP is linked not only to increased prefrontal expression of the NCAN gene itself, but also of the neighbouring HAPLN4 gene, suggesting a more complex effect of the SNP on ECM composition. Our results suggest that the NCAN rs1064395 A allele is associated with lower hippocampus-dependent memory function, variation of prefrontal cortex structure and ECM composition. Considering the well-documented hippocampal and prefrontal dysfunction in bipolar disorder and schizophrenia, our results may reflect an intermediate phenotype by which NCAN rs1064395 contributes to disease risk.


Assuntos
Transtorno Bipolar , Hipocampo , Neurocam/genética , Esquizofrenia , Mapeamento Encefálico , Proteoglicanas de Sulfatos de Condroitina/genética , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Humanos , Lectinas Tipo C/genética , Imageamento por Ressonância Magnética , Memória , Proteínas do Tecido Nervoso/genética
10.
J Physiol ; 598(4): 633-650, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31876958

RESUMO

KEY POINTS: We present a novel protocol to quantify extrasynaptic NMDA receptor function utilizing the semi-selective activation of extrasynaptic receptors by ambient extracellular glutamate in acute brain slices from adult rats. We use whole cell patch clamp to measure the effect of the NMDA receptor antagonist MK-801 on both synaptic and brief, local agonist application-evoked responses. The level of ambient glutamate was estimated from tonic NMDA receptor activity to be ∼77 nM and an equivalent concentration of NMDA was used to estimate the degree of extrasynaptic blockade (>82%) by our MK-801 protocol. The extrasynaptic component of the total NMDA receptor pool can be mathematically derived from these data and was estimated to be 29-39% in the stratum radiatum of the CA1 region of the rat hippocampus. This technique could be used to quantify extrasynaptic NMDA receptor function in rodent models of diseases where extrasynaptic NMDA receptors are implicated in neuron death. ABSTRACT: Synaptic NMDA receptors (NMDARs) play a central role in pro-survival signalling and synaptic plasticity in the majority of excitatory synapses in the central nervous system whereas extrasynaptic NMDARs (ES-NMDARs) activate pro-death pathways and have been implicated in many neurodegenerative diseases. ES-NMDARs have been characterized in acute brain slice preparations using the largely irreversible, activity-dependent NMDAR antagonist MK-801 to block synaptic NMDARs. This approach is limited by the concomitant MK-801 blockade of ES-NMDARs activated by ambient extracellular glutamate, which is largely absent from the synaptic cleft due to the high density of nearby glutamate transporters. In acute hippocampal slices from rats aged 35-42 postnatal days, we estimated ambient glutamate to be 72-83 nM resulting in a block of more than 82% of ES-NMDARs during a 5 min MK-801 application. This paper describes a novel electrophysiological and mathematical method to quantify the proportion of NMDARs located at extrasynaptic locations in a confined region of an acute brain slice preparation using MK-801 to preferentially block ES-NMDARs. The protocol uses whole cell patch clamp measurement of NMDAR responses to synaptic stimulation and brief local pressure application of NMDA before and after MK-801 application. After mathematically correcting for the relative block of both synaptic and extrasynaptic receptors, ES-NMDARs were estimated to comprise 29-39% of the total NMDAR pool in the apical dendrites of hippocampal CA1 pyramidal neurons. This new method may prove useful for accurate quantification of NMDAR distributions in neurodegenerative diseases that are associated with increased toxic ES-NMDAR signalling.


Assuntos
Maleato de Dizocilpina/farmacologia , Ácido Glutâmico/análise , Receptores de N-Metil-D-Aspartato/fisiologia , Animais , Região CA1 Hipocampal/fisiologia , Técnicas In Vitro , Técnicas de Patch-Clamp , Ratos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Sinapses/fisiologia
11.
Neuropsychobiology ; 79(6): 428-436, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32182618

RESUMO

Resting-state and event-related frontal alpha asymmetry have been suggested as potential neurobiological biomarkers for depression and other psychiatric conditions. To be used as such, sufficient test-retest reliability needs to be demonstrated. However, test-retest reliability is underinvestigated for event-related alpha asymmetry. The objective of this study was to examine both short-term within-session and long-term between-session reliability of stimulus-related medial and lateral frontal as well as parietal alpha EEG asymmetry in healthy subjects during a simple emotional face processing task. Twenty-three healthy adults participated in two sessions with a test-retest interval of about 1 week. Reliability was estimated with Pearson's correlation coefficient and paired t test. Results revealed moderate to high within-session reliability of stimulus-related alpha asymmetry for all electrode sites and both conditions. Alpha asymmetry mean values did not change significantly within sessions. Between-session reliability was fair for frontomedial and moderate for frontolateral stimulus-related asymmetry. Exploratory exclusion of subjects with unstable between-session self-rating scores of emotional state and empathy toward stimuli resulted in some higher reliability values. Our results indicate that stimulus-related alpha asymmetry may serve as a useful electrophysiological tool given its adequate within-session reliability. However, long-term stability of stimulus-related frontal alpha asymmetry over 1 week was comparatively low and varied depending on electrode position. Influencing state factors during EEG recording, such as current mood or stimulus engagement, should be considered in future study designs and analyses. Further, we recommend to analyze alpha asymmetry from both frontomedial and frontolateral sites.


Assuntos
Ritmo alfa/fisiologia , Emoções/fisiologia , Empatia/fisiologia , Reconhecimento Facial/fisiologia , Lobo Frontal/fisiologia , Lobo Parietal/fisiologia , Adulto , Expressão Facial , Feminino , Voluntários Saudáveis , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
12.
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
16.
Eur J Neurosci ; 45(1): 129-137, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27628616

RESUMO

Adolescence is a critical maturation period for human cognitive control and executive function. In this study, a large sample of adolescents (n = 85) performed a reversal learning task during functional magnetic resonance imaging. We analyzed behavioral data using a reinforcement learning model to provide individually fitted parameters and imaging data with regard to reward prediction errors (PE). Following a model-based approach, we formed two groups depending on whether individuals tended to update expectations predominantly for the chosen stimulus or also for the unchosen one. These groups significantly differed in their problem behavior score obtained using the child behavior checklist (CBCL) and in a measure of their developmental stage. Imaging results showed that dorsolateral striatal areas covaried with PE. Participants who relied less on learning based on task structure showed less prefrontal activation compared with participants who relied more on task structure. An exploratory analysis revealed that PE-related activity was associated with pubertal development in prefrontal areas, insula and anterior cingulate. These findings support the hypothesis that the prefrontal cortex is implicated in mediating flexible goal-directed behavioral control.


Assuntos
Mapeamento Encefálico , Função Executiva/fisiologia , Córtex Pré-Frontal/fisiologia , Reversão de Aprendizagem/fisiologia , Adolescente , Envelhecimento , Feminino , Giro do Cíngulo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Reforço Psicológico , Recompensa
18.
J Neurosci ; 35(28): 10103-11, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26180188

RESUMO

The striatum is known to play a key role in reinforcement learning, specifically in the encoding of teaching signals such as reward prediction errors (RPEs). It has been proposed that aberrant salience attribution is associated with impaired coding of RPE and heightened dopamine turnover in the striatum, and might be linked to the development of psychotic symptoms. However, the relationship of aberrant salience attribution, RPE coding, and dopamine synthesis capacity has not been directly investigated. Here we assessed the association between a behavioral measure of aberrant salience attribution, the salience attribution test, to neural correlates of RPEs measured via functional magnetic resonance imaging while healthy participants (n = 58) performed an instrumental learning task. A subset of participants (n = 27) also underwent positron emission tomography with the radiotracer [(18)F]fluoro-l-DOPA to quantify striatal presynaptic dopamine synthesis capacity. Individual variability in aberrant salience measures related negatively to ventral striatal and prefrontal RPE signals and in an exploratory analysis was found to be positively associated with ventral striatal presynaptic dopamine levels. These data provide the first evidence for a specific link between the constructs of aberrant salience attribution, reduced RPE processing, and potentially increased presynaptic dopamine function.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Sintomas Prodrômicos , Transtornos Psicóticos/diagnóstico , Reforço Psicológico , Adolescente , Adulto , Condicionamento Operante , Corpo Estriado/irrigação sanguínea , Corpo Estriado/diagnóstico por imagem , Dopaminérgicos , Feminino , Fluordesoxiglucose F18 , Humanos , Processamento de Imagem Assistida por Computador , Levodopa , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Tomografia por Emissão de Pósitrons , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/fisiopatologia , Tempo de Reação , Adulto Jovem
19.
Eur J Neurosci ; 41(1): 31-44, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25306895

RESUMO

Stressful experiences do not only cause peripheral changes in stress hormone levels, but also affect central structures such as the hippocampus, implicated in spatial orientation, stress evaluation, and learning and memory. It has been suggested that formation of memory traces is dependent on hippocampal gamma oscillations observed during alert behaviour and rapid eye movement sleep. Furthermore, during quiescent behaviour, sharp wave-ripple (SW-R) activity emerges. These events provide a temporal window during which reactivation of memory ensembles occur. We hypothesized that stress-responsive modulators, such as corticosterone (CORT), corticotropin-releasing factor (CRF) and the neurosteroid 3α, 21-dihydroxy-5α-pregnan-20-one (THDOC) are able to modulate gamma oscillations and SW-Rs. Using in vitro hippocampal slices, we studied acute and subacute (2 h) impact of these agents on gamma oscillations in area cornu ammonis 3 of the ventral hippocampus induced by acetylcholine (10 µm) combined with physostigmine (2 µm). CORT increased the gamma oscillations in a dose-dependent fashion. This effect was mediated by glucocorticoid receptors. Likewise, CRF augmented gamma oscillations via CRF type 1 receptor. Lastly, THDOC was found to diminish cholinergic gamma oscillations in a dose-dependent manner. Neither CORT, CRF nor THDOC modulated gamma power when pre-applied for 1 h, 2 h before the induction of gamma oscillations. Interestingly, stress-related neuromodulators had rather mild effects on spontaneous SW-R compared with their effects on gamma oscillations. These data suggest that the alteration of hippocampal gamma oscillation strength in vitro by stress-related agents is an acute process, permitting fast adaptation to new attention-requiring situations in vivo.


Assuntos
Corticosterona/metabolismo , Hormônio Liberador da Corticotropina/metabolismo , Ritmo Gama/fisiologia , Hipocampo/fisiologia , Acetilcolina/metabolismo , Animais , Inibidores da Colinesterase/farmacologia , Desoxicorticosterona/análogos & derivados , Desoxicorticosterona/farmacologia , Relação Dose-Resposta a Droga , Ritmo Gama/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Masculino , Neurotransmissores/farmacologia , Fisostigmina/farmacologia , Ratos Wistar , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Receptores de Glucocorticoides/metabolismo , Fatores de Tempo , Técnicas de Cultura de Tecidos
20.
Front Cell Neurosci ; 18: 1368627, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716238

RESUMO

The balance between excitation and inhibition is essential to the proper function of cortical circuits. To maintain this balance during dynamic network activity, modulation of the strength of inhibitory synapses is a central requirement. In this study, we aimed to characterize perisomatic inhibition and its plasticity onto pyramidal cells (PCs) in the subiculum, the main output region of the hippocampus. We performed whole-cell patch-clamp recordings from the two main functional PC types, burst (BS) and regular spiking (RS) neurons in acute rat hippocampal slices and applied two different extracellular high-frequency stimulation paradigms: non-associative (presynaptic stimulation only) and associative stimulation (concurrent pre-and postsynaptic stimulation) to induce plasticity. Our results revealed cell type-specific differences in the expression of inhibitory plasticity depending on the induction paradigm: While associative stimulation caused robust inhibitory plasticity in both cell types, non-associative stimulation produced long-term potentiation in RS, but not in BS PCs. Analysis of paired-pulse ratio, variance of IPSPs, and postsynaptic Ca2+ buffering indicated a dominant postsynaptic calcium-dependent signaling and expression of inhibitory plasticity in both PC types. This divergence in inhibitory plasticity complements a stronger inhibition and a higher intrinsic excitability in RS as compared to BS neurons, suggesting differential involvement of the two PC types during network activation and information processing in the subiculum.

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