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1.
Addict Biol ; 29(7): e13419, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38949209

RESUMEN

Substance use disorders (SUDs) are seen as a continuum ranging from goal-directed and hedonic drug use to loss of control over drug intake with aversive consequences for mental and physical health and social functioning. The main goals of our interdisciplinary German collaborative research centre on Losing and Regaining Control over Drug Intake (ReCoDe) are (i) to study triggers (drug cues, stressors, drug priming) and modifying factors (age, gender, physical activity, cognitive functions, childhood adversity, social factors, such as loneliness and social contact/interaction) that longitudinally modulate the trajectories of losing and regaining control over drug consumption under real-life conditions. (ii) To study underlying behavioural, cognitive and neurobiological mechanisms of disease trajectories and drug-related behaviours and (iii) to provide non-invasive mechanism-based interventions. These goals are achieved by: (A) using innovative mHealth (mobile health) tools to longitudinally monitor the effects of triggers and modifying factors on drug consumption patterns in real life in a cohort of 900 patients with alcohol use disorder. This approach will be complemented by animal models of addiction with 24/7 automated behavioural monitoring across an entire disease trajectory; i.e. from a naïve state to a drug-taking state to an addiction or resilience-like state. (B) The identification and, if applicable, computational modelling of key molecular, neurobiological and psychological mechanisms (e.g., reduced cognitive flexibility) mediating the effects of such triggers and modifying factors on disease trajectories. (C) Developing and testing non-invasive interventions (e.g., Just-In-Time-Adaptive-Interventions (JITAIs), various non-invasive brain stimulations (NIBS), individualized physical activity) that specifically target the underlying mechanisms for regaining control over drug intake. Here, we will report on the most important results of the first funding period and outline our future research strategy.


Asunto(s)
Trastornos Relacionados con Sustancias , Humanos , Animales , Alemania , Conducta Adictiva , Alcoholismo
2.
Gen Psychiatr ; 37(3): e101486, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38859926

RESUMEN

Background: Attention-deficit/hyperactivity disorder (ADHD) is one of the most frequently diagnosed psychiatric conditions in children and adolescents. Although the symptoms appear to be well described, no coherent conceptual mechanistic framework integrates their occurrence and variance and the associated problems that people with ADHD face. Aims: The current study proposes that altered event segmentation processes provide a novel mechanistic framework for understanding deficits in ADHD. Methods: Adolescents with ADHD and neurotypically developing (NT) peers watched a short movie and were then asked to indicate the boundaries between meaningful segments of the movie. Concomitantly recorded electroencephalography (EEG) data were analysed for differences in frequency band activity and effective connectivity between brain areas. Results: Compared with their NT peers, the ADHD group showed less dependence of their segmentation behaviour on social information, indicating that they did not consider social information to the same extent as their unaffected peers. This divergence was accompanied by differences in EEG theta band activity and a different effective connectivity network architecture at the source level. Specifically, NT adolescents primarily showed error signalling in and between the left and right fusiform gyri related to social information processing, which was not the case in the ADHD group. For the ADHD group, the inferior frontal cortex associated with attentional sampling served as a hub instead, indicating problems in the deployment of attentional control. Conclusions: This study shows that adolescents with ADHD perceive events differently from their NT peers, in association with a different brain network architecture that reflects less adaptation to the situation and problems in attentional sampling of environmental information. The results call for a novel conceptual view of ADHD, based on event segmentation theory.

3.
Commun Biol ; 7(1): 759, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38909084

RESUMEN

That younger individuals perceive the world as moving slower than adults is a familiar phenomenon. Yet, it remains an open question why that is. Using event segmentation theory, electroencephalogram (EEG) beamforming and nonlinear causal relationship estimation using artificial neural network methods, we studied neural activity while adolescent and adult participants segmented a movie. We show when participants were instructed to segment a movie into meaningful units, adolescents partitioned incoming information into fewer encapsulated segments or episodes of longer duration than adults. Importantly, directed communication between medial frontal and lower-level perceptual areas and between occipito-temporal regions in specific neural oscillation spectrums explained behavioral differences between groups. Overall, the study reveals that a different organization of directed communication between brain regions and inefficient transmission of information between brain regions are key to understand why younger people perceive the world as moving slow.


Asunto(s)
Electroencefalografía , Humanos , Adolescente , Masculino , Femenino , Adulto , Adulto Joven , Encéfalo/fisiología , Percepción de Movimiento/fisiología , Redes Neurales de la Computación
4.
Hum Brain Mapp ; 45(8): e26719, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38826009

RESUMEN

Gilles de la Tourette syndrome (GTS) is a disorder characterised by motor and vocal tics, which may represent habitual actions as a result of enhanced learning of associations between stimuli and responses (S-R). In this study, we investigated how adults with GTS and healthy controls (HC) learn two types of regularities in a sequence: statistics (non-adjacent probabilities) and rules (predefined order). Participants completed a visuomotor sequence learning task while EEG was recorded. To understand the neurophysiological underpinnings of these regularities in GTS, multivariate pattern analyses on the temporally decomposed EEG signal as well as sLORETA source localisation method were conducted. We found that people with GTS showed superior statistical learning but comparable rule-based learning compared to HC participants. Adults with GTS had different neural representations for both statistics and rules than HC adults; specifically, adults with GTS maintained the regularity representations longer and had more overlap between them than HCs. Moreover, over different time scales, distinct fronto-parietal structures contribute to statistical learning in the GTS and HC groups. We propose that hyper-learning in GTS is a consequence of the altered sensitivity to encode complex statistics, which might lead to habitual actions.


Asunto(s)
Electroencefalografía , Síndrome de Tourette , Humanos , Síndrome de Tourette/fisiopatología , Masculino , Adulto , Femenino , Adulto Joven , Aprendizaje/fisiología , Desempeño Psicomotor/fisiología , Persona de Mediana Edad , Aprendizaje por Probabilidad
5.
Neuroimage ; 295: 120667, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38825216

RESUMEN

Executive functions are essential for adaptive behavior. One executive function is the so-called 'interference control' or conflict monitoring another one is inhibitory control (i.e., action restraint and action cancelation). Recent evidence suggests an interplay of these processes, which is conceptually relevant given that newer conceptual frameworks imply that nominally different action/response control processes are explainable by a small set of cognitive and neurophysiological processes. The existence of such overarching neural principles has as yet not directly been examined. In the current study, we therefore use EEG tensor decomposition methods, to look into possible common neurophysiological signatures underlying conflict-modulated action restraint and action cancelation as mechanism underlying response inhibition. We show how conflicts differentially modulate action restraint and action cancelation processes and delineate common and distinct neural processes underlying this interplay. Concerning the spatial information modulations are similar in terms of an importance of processes reflected by parieto-occipital electrodes, suggesting that attentional selection processes play a role. Especially theta and alpha activity seem to play important roles. The data also show that tensor decomposition is sensitive to the manner of task implementation, thereby suggesting that switch probability/transitional probabilities should be taken into consideration when choosing tensor decomposition as analysis method. The study provides a blueprint of how to use tensor decomposition methods to delineate common and distinct neural mechanisms underlying action control functions using EEG data.


Asunto(s)
Conflicto Psicológico , Electroencefalografía , Función Ejecutiva , Humanos , Electroencefalografía/métodos , Masculino , Función Ejecutiva/fisiología , Femenino , Adulto , Adulto Joven , Encéfalo/fisiología , Inhibición Psicológica , Desempeño Psicomotor/fisiología
6.
Int J Neuropsychopharmacol ; 27(6)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38742426

RESUMEN

BACKGROUND: The principle of gain control determines the efficiency of neuronal processing and can be enhanced with pharmacological or brain stimulation methods. It is a key factor for cognitive control, but the degree of how much gain control may be enhanced underlies a physical limit. METHODS: To investigate whether methylphenidate (MPH) and transcranial direct current stimulation (tDCS) share common underlying mechanisms and cognitive effects, we administered MPH and anodal tDCS (atDCS) over the right inferior frontal gyrus both separately and combined, while healthy adult participants (n = 104) performed a response selection and inhibition task. The recorded EEG data were analyzed with a focus on theta band activity, and source estimation analyses were conducted. RESULTS: The behavioral data show that MPH and atDCS revealed interactive effects on the ability to inhibit responses. Both MPH and atDCS modulated task-related theta oscillations in the supplementary motor area when applied separately, making a common underlying mechanism likely. When both stimulation methods were combined, there was no doubling of effects in the supplementary motor area but a shift to inferior frontal areas in the cortical network responsible for theta-driven processing. CONCLUSIONS: The results indicate that both MPH and atDCS likely share a common underlying neuronal mechanism, and interestingly, they demonstrate interactive effects when combined, which are most likely due to the physical limitations of gain control increases. The current study provides critical groundwork for future combined applications of MPH and non-invasive brain stimulation.


Asunto(s)
Inhibición Psicológica , Metilfenidato , Ritmo Teta , Estimulación Transcraneal de Corriente Directa , Humanos , Masculino , Femenino , Adulto , Adulto Joven , Metilfenidato/farmacología , Ritmo Teta/fisiología , Ritmo Teta/efectos de los fármacos , Electroencefalografía , Estimulantes del Sistema Nervioso Central/farmacología , Corteza Prefrontal/fisiología , Corteza Prefrontal/efectos de los fármacos , Corteza Motora/fisiología , Corteza Motora/efectos de los fármacos
7.
Behav Brain Res ; 469: 115063, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38777262

RESUMEN

Goal-directed acting requires the integration of sensory information but can also be performed without direct sensory input. Examples of this can be found in sports and can be conceptualized by feedforward processes. There is, however, still a lack of understanding of the temporal neural dynamics and neuroanatomical structures involved in such processes. In the current study, we used EEG beamforming methods and examined 37 healthy participants in two well-controlled experiments varying the necessity of anticipatory processes during goal-directed action. We found that alpha and beta activity in the medial and posterior cingulate cortex enabled feedforward predictions about the position of an object based on the latest sensorimotor state. On this basis, theta band activity seems more related to sensorimotor representations, while beta band activity would be more involved in setting up the structure of the neural representations themselves. Alpha band activity in sensory cortices reflects an intensified gating of the anticipated perceptual consequences of the to-be-executed action. Together, the findings indicate that goal-directed acting through the anticipation of the predicted state of an effector is based on accompanying processes in multiple frequency bands in midcingulate and sensory brain regions.


Asunto(s)
Electroencefalografía , Imaginación , Humanos , Masculino , Femenino , Adulto , Adulto Joven , Imaginación/fisiología , Objetivos , Encéfalo/fisiología , Ritmo alfa/fisiología , Giro del Cíngulo/fisiología , Anticipación Psicológica/fisiología , Ritmo beta/fisiología , Desempeño Psicomotor/fisiología , Ondas Encefálicas/fisiología
8.
Commun Biol ; 7(1): 626, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789522

RESUMEN

We delve into the human brain's remarkable capacity for adaptability and sustained cognitive functioning, phenomena traditionally encompassed as executive functions or cognitive control. The neural underpinnings that enable the seamless navigation between transient thoughts without detracting from overarching goals form the core of our article. We discuss the concept of "metacontrol," which builds upon conventional cognitive control theories by proposing a dynamic balancing of processes depending on situational demands. We critically discuss the role of oscillatory processes in electrophysiological activity at different scales and the importance of desynchronization and partial phase synchronization in supporting adaptive behavior including neural noise accounts, transient dynamics, phase-based measures (coordination dynamics) and neural mass modelling. The cognitive processes focused and neurophysiological avenues outlined are integral to understanding diverse psychiatric disorders thereby contributing to a more nuanced comprehension of cognitive control and its neural bases in both health and disease.


Asunto(s)
Encéfalo , Cognición , Humanos , Encéfalo/fisiología , Cognición/fisiología , Función Ejecutiva/fisiología , Modelos Neurológicos
9.
Cereb Cortex ; 34(5)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38771238

RESUMEN

Cognitive-control theories assume that the experience of response conflict can trigger control adjustments. However, while some approaches focus on adjustments that impact the selection of the present response (in trial N), other approaches focus on adjustments in the next upcoming trial (N + 1). We aimed to trace control adjustments over time by quantifying cortical noise by means of the fitting oscillations and one over f algorithm, a measure of aperiodic activity. As predicted, conflict trials increased the aperiodic exponent in a large sample of 171 healthy adults, thus indicating noise reduction. While this adjustment was visible in trial N already, it did not affect response selection before the next trial. This suggests that control adjustments do not affect ongoing response-selection processes but prepare the system for tighter control in the next trial. We interpret the findings in terms of a conflict-induced switch from metacontrol flexibility to metacontrol persistence, accompanied or even implemented by a reduction of cortical noise.


Asunto(s)
Cognición , Conflicto Psicológico , Electroencefalografía , Humanos , Masculino , Femenino , Adulto , Adulto Joven , Cognición/fisiología , Encéfalo/fisiología , Adolescente
10.
Psychol Res ; 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38733538

RESUMEN

Interacting with our environment happens on different levels of complexity: While there are individual and simple actions like an isolated button press, most actions are more complex and involve sequences of simpler actions. The degree to which multiple simple actions are represented as one action sequence can be measured via so-called response-response binding effects. When two or more responses are executed consecutively, they are integrated into one representation so that repetition of one response can start retrieval of the other. Executing such an action sequence typically involves responding to multiple objects or stimuli. Here, we investigated whether the spatial relation of these stimuli affects action sequence execution. To that end, we varied the distance between stimuli in a response-response binding task. Stimulus distance might affect response-response binding effects in one of two ways: It might directly affect the representation of the response sequence, making integration and retrieval between responses more likely if the responses relate to close stimuli. Alternatively, the similarity of stimulus distribution during integration and retrieval might be decisive, leading to larger binding effects if stimulus distance is identical during integration and retrieval. We found stronger binding effects with constant than with changing stimulus distance, indicating that action integration and retrieval can easily affect performance also if responses refer to separated objects. However, this effect on performance is diminished by changing spatial distribution of stimuli at the times of integration and retrieval.

11.
iScience ; 27(4): 109521, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38591012

RESUMEN

To facilitate goal-directed actions, effective management of working memory (WM) is crucial, involving a hypothesized WM "gating mechanism." We investigate the underlying neural basis through behavioral modeling and connectivity assessments between neuroanatomical regions linked to theta, alpha, and beta frequency bands. We found opposing, threshold-dependent mechanisms governing WM gate opening and closing. Directed beta band connectivity in the parieto-frontal and parahippocampal-occipital networks was crucial for threshold-dependent WM gating dynamics. Fronto-parahippocampal connectivity in the theta band was also notable for both gating processes, although weaker than that in the beta band. Distinct roles for theta, beta, and alpha bands emerge in maintaining information in WM and shielding against interference, whereby alpha band activity likely acts as a "gatekeeper" supporting processes reflected by beta and theta band activity. The study shows that the decision criterion for WM gate opening/closing relies on concerted interplay within neuroanatomical networks defined by beta and theta band activities.

12.
Eur Neuropsychopharmacol ; 83: 43-54, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38642447

RESUMEN

Methamphetamine (METH, "Crystal Meth") and 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy") share structural-chemical similarities but have distinct psychotropic profiles due to specific neurochemical actions. Previous research has suggested that their impact on social cognitive functions and social behaviour may differ significantly, however, direct comparisons of METH and MDMA users regarding social cognition and interaction are lacking. Performances in cognitive and emotional empathy (Multifaceted Empathy Test) and emotion sensitivity (Face Morphing Task), as well as aggressive social behaviour (Competitive Reaction Time Task) were assessed in samples of n = 40 chronic METH users, n = 39 chronic MDMA users and n = 86 stimulant-naïve controls (total N = 165). Self-reports and hair samples were used to obtain subjective and objective estimates of substance use patterns. METH users displayed diminished cognitive and emotional empathy towards positive stimuli, elevated punitive social behaviour regardless of provocation, and self-reported heightened trait anger relative to controls. MDMA users diverged from the control group only by exhibiting a distinct rise in punitive behaviour when faced with provocation. Correlation analyses indicated that both higher hair concentrations of MDMA and METH may be associated with reduced cognitive empathy. Moreover, greater lifetime MDMA use correlated with increased punitive behaviour among MDMA users. Our findings confirm elevated aggression and empathy deficits in chronic METH users, while chronic MDMA users only displayed more impulsive aggression. Dose-response correlations indicate that some of these deficits might be a consequence of use. Specifically, the dopaminergic mechanism of METH might be responsible for social-cognitive deficits.


Asunto(s)
Agresión , Trastornos Relacionados con Anfetaminas , Empatía , Metanfetamina , N-Metil-3,4-metilenodioxianfetamina , Humanos , N-Metil-3,4-metilenodioxianfetamina/efectos adversos , Masculino , Agresión/efectos de los fármacos , Agresión/psicología , Femenino , Adulto , Metanfetamina/efectos adversos , Metanfetamina/administración & dosificación , Empatía/efectos de los fármacos , Empatía/fisiología , Adulto Joven , Trastornos Relacionados con Anfetaminas/psicología , Cabello/química , Conducta Social , Cognición/efectos de los fármacos , Cognición/fisiología , Alucinógenos/administración & dosificación , Alucinógenos/efectos adversos , Autoinforme , Emociones/efectos de los fármacos , Emociones/fisiología , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Adolescente
13.
Brain Commun ; 6(2): fcae092, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38562308

RESUMEN

Gilles de la Tourette syndrome is a neurodevelopmental disorder characterized by motor and vocal tics. It is associated with enhanced processing of stimulus-response associations, including a higher propensity to learn probabilistic stimulus-response contingencies (i.e. statistical learning), the nature of which is still elusive. In this study, we investigated the hypothesis that resting-state theta network organization is a key for the understanding of superior statistical learning in these patients. We investigated the graph-theoretical network architecture of theta oscillations in adult patients with Gilles de la Tourette syndrome and healthy controls during a statistical learning task and in resting states both before and after learning. We found that patients with Gilles de la Tourette syndrome showed a higher statistical learning score than healthy controls, as well as a more optimal (small-world-like) theta network before the task. Thus, patients with Gilles de la Tourette syndrome had a superior facility to integrate and evaluate novel information as a trait-like characteristic. Additionally, the theta network architecture in Gilles de la Tourette syndrome adapted more to the statistical information during the task than in HC. We suggest that hyper-learning in patients with Gilles de la Tourette syndrome is likely a consequence of increased sensitivity to perceive and integrate sensorimotor information leveraged through theta oscillation-based resting-state dynamics. The study delineates the neural basis of a higher propensity in patients with Gilles de la Tourette syndrome to pick up statistical contingencies in their environment. Moreover, the study emphasizes pathophysiologically endowed abilities in patients with Gilles de la Tourette syndrome, which are often not taken into account in the perception of this common disorder but could play an important role in destigmatization.

14.
Hum Brain Mapp ; 45(6): e26643, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38664992

RESUMEN

Coping with distracting inputs during goal-directed behavior is a common challenge, especially when stopping ongoing responses. The neural basis for this remains debated. Our study explores this using a conflict-modulation Stop Signal task, integrating group independent component analysis (group-ICA), multivariate pattern analysis (MVPA), and EEG source localization analysis. Consistent with previous findings, we show that stopping performance is better in congruent (nonconflicting) trials than in incongruent (conflicting) trials. Conflict effects in incongruent trials compromise stopping more due to the need for the reconfiguration of stimulus-response (S-R) mappings. These cognitive dynamics are reflected by four independent neural activity patterns (ICA), each coding representational content (MVPA). It is shown that each component was equally important in predicting behavioral outcomes. The data support an emerging idea that perception-action integration in action-stopping involves multiple independent neural activity patterns. One pattern relates to the precuneus (BA 7) and is involved in attention and early S-R processes. Of note, three other independent neural activity patterns were associated with the insular cortex (BA13) in distinct time windows. These patterns reflect a role in early attentional selection but also show the reiterated processing of representational content relevant for stopping in different S-R mapping contexts. Moreover, the insular cortex's role in automatic versus complex response selection in relation to stopping processes is shown. Overall, the insular cortex is depicted as a brain hub, crucial for response selection and cancellation across both straightforward (automatic) and complex (conditional) S-R mappings, providing a neural basis for general cognitive accounts on action control.


Asunto(s)
Conflicto Psicológico , Electroencefalografía , Inhibición Psicológica , Corteza Insular , Humanos , Masculino , Femenino , Adulto , Adulto Joven , Corteza Insular/fisiología , Corteza Insular/diagnóstico por imagen , Mapeo Encefálico , Atención/fisiología , Desempeño Psicomotor/fisiología , Corteza Cerebral/fisiología , Corteza Cerebral/diagnóstico por imagen
15.
Neuroimage ; 293: 120619, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38679186

RESUMEN

Catecholamines and amino acid transmitter systems are known to interact, the exact links and their impact on cognitive control functions have however remained unclear. Using a multi-modal imaging approach combining EEG and proton-magnetic resonance spectroscopy (1H-MRS), we investigated the effect of different degrees of pharmacological catecholaminergic enhancement onto theta band activity (TBA) as a measure of interference control during response inhibition and execution. It was central to our study to evaluate the predictive impact of in-vivo baseline GABA+ concentrations in the striatum, the anterior cingulate cortex (ACC) and the supplemental motor area (SMA) of healthy adults under varying degrees of methylphenidate (MPH) stimulation. We provide evidence for a predictive interrelation of baseline GABA+ concentrations in cognitive control relevant brain areas onto task-induced TBA during response control stimulated with MPH. Baseline GABA+ concentrations in the ACC, the striatum, and the SMA had a differential impact on predicting interference control-related TBA in response execution trials. GABA+ concentrations in the ACC appeared to be specifically important for TBA modulations when the cognitive effort needed for interference control was high - that is when no prior task experience exists, or in the absence of catecholaminergic enhancement with MPH. The study highlights the predictive role of baseline GABA+ concentrations in key brain areas influencing cognitive control and responsiveness to catecholaminergic enhancement, particularly in high-effort scenarios.


Asunto(s)
Catecolaminas , Cognición , Electroencefalografía , Metilfenidato , Espectroscopía de Protones por Resonancia Magnética , Ácido gamma-Aminobutírico , Humanos , Ácido gamma-Aminobutírico/metabolismo , Masculino , Adulto , Femenino , Adulto Joven , Espectroscopía de Protones por Resonancia Magnética/métodos , Catecolaminas/metabolismo , Metilfenidato/farmacología , Electroencefalografía/métodos , Cognición/fisiología , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagen , Giro del Cíngulo/metabolismo , Giro del Cíngulo/diagnóstico por imagen , Giro del Cíngulo/efectos de los fármacos , Ritmo Teta/fisiología , Ritmo Teta/efectos de los fármacos , Función Ejecutiva/fisiología , Función Ejecutiva/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacología
16.
Ageing Res Rev ; 96: 102280, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38518921

RESUMEN

The retina has been considered a "window to the brain" and shares similar innervation by the dopaminergic system with the cortex in terms of an unequal distribution of D1 and D2 receptors. Here, we provide a comprehensive overview that Optical Coherence Tomography (OCT), a non-invasive imaging technique, which provides an "in vivo" representation of the retina, shows promise to be used as a surrogate marker of dopaminergic neuromodulation in cognition. Overall, most evidence supports reduced retinal thickness in individuals with dopaminergic dysregulation (e.g., patients with Parkinson's Disease, non-demented older adults) and with poor cognitive functioning. By using the theoretical framework of metacontrol, we derive hypotheses that retinal thinning associated to decreased dopamine (DA) levels affecting D1 families, might lead to a decrease in the signal-to-noise ratio (SNR) affecting cognitive persistence (depending on D1-modulated DA activity) but not cognitive flexibility (depending on D2-modulated DA activity). We argue that the use of OCT parameters might not only be an insightful for cognitive neuroscience research, but also a potentially effective tool for individualized medicine with a focus on cognition. As our society progressively ages in the forthcoming years and decades, the preservation of cognitive abilities and promoting healthy aging will hold of crucial significance. OCT has the potential to function as a swift, non-invasive, and economical method for promptly recognizing individuals with a heightened vulnerability to cognitive deterioration throughout all stages of life.


Asunto(s)
Dopamina , Longevidad , Humanos , Anciano , Tomografía de Coherencia Óptica , Cognición/fisiología , Retina/diagnóstico por imagen , Biomarcadores
17.
Psychophysiology ; : e14576, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38556626

RESUMEN

The ability to find the right balance between more persistent and more flexible cognitive-control styles is known as "metacontrol." Recent findings suggest a relevance of aperiodic EEG activity and task conditions that are likely to elicit a specific metacontrol style. Here we investigated whether individual differences in aperiodic EEG activity obtained off-task (during resting state) predict individual cognitive-control styles under task conditions that pose different demands on metacontrol. We analyzed EEG resting-state data, task-EEG, and behavioral outcomes from a sample of N = 65 healthy participants performing a Go/Nogo task. We examined aperiodic activity as indicator of "neural noise" in the EEG power spectrum, and participants were assigned to a high-noise or low-noise group according to a median split of the exponents obtained for resting state. We found that off-task aperiodic exponents predicted different cognitive-control styles in Go and Nogo conditions: Overall, aperiodic exponents were higher (i.e., noise was lower) in the low-noise group, who however showed no difference between Go and Nogo trials, whereas the high-noise group exhibited significant noise reduction in the more persistence-heavy Nogo condition. This suggests that trait-like biases determine the default cognitive-control style, which however can be overwritten or compensated for under challenging task demands. We suggest that aperiodic activity in EEG signals represents valid indicators of highly dynamic arbitration between metacontrol styles, representing the brain's capability to reorganize itself and adapt its neural activity patterns to changing environmental conditions.

18.
Neuroimage Clin ; 41: 103579, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38447413

RESUMEN

In stimulant use and addiction, conflict control processes are crucial for regulating substance use and sustaining abstinence, which can be particularly challenging in social-affective situations. Users of methamphetamine (METH, "Ice") and 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy") both experience impulse control deficits, but display different social-affective and addictive profiles. We thus aimed to compare the effects of chronic use of the substituted amphetamines METH and MDMA on conflict control processes in different social-affective contexts (i.e., anger and happiness) and investigate their underlying neurophysiological mechanisms. For this purpose, chronic but recently abstinent users of METH (n = 38) and MDMA (n = 42), as well as amphetamine-naïve healthy controls (n = 83) performed an emotional face-word Stroop paradigm, while event-related potentials (ERPs) were recorded. Instead of substance-specific differences, both MDMA and METH users showed smaller behavioral effects of cognitive-emotional conflict processing (independently of emotional valence) and selective deficits in emotional processing of anger content. Both effects were underpinned by stronger P3 ERP modulations suggesting that users of substituted amphetamines employ altered stimulus-response mapping and decision-making. Given that these processes are modulated by noradrenaline and that both MDMA and METH use may be associated with noradrenergic dysfunctions, the noradrenaline system may underlie the observed substance-related similarities. Better understanding the functional relevance of this currently still under-researched neurotransmitter and its functional changes in chronic users of substituted amphetamines is thus an important avenue for future research.


Asunto(s)
Metanfetamina , N-Metil-3,4-metilenodioxianfetamina , Trastornos Relacionados con Sustancias , Humanos , N-Metil-3,4-metilenodioxianfetamina/farmacología , Metanfetamina/farmacología , Anfetaminas , Norepinefrina
19.
Acta Psychol (Amst) ; 244: 104190, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38368782

RESUMEN

In the literature on human action control, it is assumed that features of stimuli (S) and responses (R) are integrated into internal representations (so-called event files) that are involved in the execution of an action. Experimentally, the impact of this integration on action control is typically analyzed via S-R binding effects. Recent theorizing in the BRAC framework (Frings et al., 2020) suggests to disentangle the processes of S-R binding proper from S-R retrieval as two independent components contributing to S-R binding effects. Since the literature on age effects on S-R binding effects is scarce and does not provide information on whether the existing findings about the two processes can be generalized to older age groups, this is the first study addressing the effects of older age separately on S-R binding proper vs. S-R retrieval. In two established variants of S-R binding tasks (cumulative n = 262), we contrasted binding (by using a saliency manipulation at the time of binding proper) versus retrieval processes (by manipulating the onset of the distractor at the time of retrieval), replicating previous results in younger (18-30 years) and also in older healthy controls (50-70 years). We therefore found no evidence for age effects on S-R binding proper or S-R retrieval. We thus conclude that the processes contributing to S-R binding effects are - at least in the age groups analyzed in this study - robust and age-independent. STATEMENT OF SIGNIFICANCE: In human action control, binding proper and retrieval of features in stimulus-response episodes typically lead to so-called S-R binding effects. Against the background of recent theorizing, binding proper and retrieval should be studied independently. In this article, we ran a younger and an older age group and analyzed possible age-related differences in integration or retrieval. Both groups showed the expected pattern for binding and retrieval as expected from the literature.


Asunto(s)
Atención , Humanos , Anciano , Tiempo de Reacción/fisiología , Atención/fisiología
20.
Neuroimage ; 289: 120541, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38360384

RESUMEN

Our everyday activities require the maintenance and continuous updating of information in working memory (WM). To control this dynamic, WM gating mechanisms have been suggested to be in place, but the neurophysiological mechanisms behind these processes are far from being understood. This is especially the case when it comes to the role of oscillatory neural activity. In the current study we combined EEG recordings, and anodal transcranial direct current stimulation (atDCS) and pupil diameter recordings to triangulate neurophysiology, functional neuroanatomy and neurobiology. The results revealed that atDCS, compared to sham stimulation, affected the WM gate opening mechanism, but not the WM gate closing mechanism. The altered behavioral performance was associated with specific changes in alpha band activities (reflected by alpha desynchronization), indicating a role for inhibitory control during WM gate opening. Functionally, the left superior and inferior parietal cortices, were associated with these processes. The findings are the first to show a causal relevance of alpha desynchronization processes in WM gating processes. Notably, pupil diameter recordings as an indirect index of the norepinephrine (NE) system activity revealed that individuals with stronger inhibitory control (as indexed through alpha desynchronization) showed less pupil dilation, suggesting they needed less NE activity to support WM gate opening. However, when atDCS was applied, this connection disappeared. The study suggests a close link between inhibitory controlled WM gating in parietal cortices, alpha band dynamics and the NE system.


Asunto(s)
Memoria a Corto Plazo , Estimulación Transcraneal de Corriente Directa , Humanos , Memoria a Corto Plazo/fisiología , Norepinefrina , Lóbulo Parietal/fisiología
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