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1.
Proc Natl Acad Sci U S A ; 120(46): e2302655120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37934822

RESUMO

Reading danger signals may save an animal's life, and learning about threats from others allows avoiding first-hand aversive and often fatal experiences. Fear expressed by other individuals, including those belonging to other species, may indicate the presence of a threat in the environment and is an important social cue. Humans and other animals respond to conspecifics' fear with increased activity of the amygdala, the brain structure crucial for detecting threats and mounting an appropriate response to them. It is unclear, however, whether the cross-species transmission of threat information involves similar mechanisms, e.g., whether animals respond to the aversively induced emotional arousal of humans with activation of fear-processing circuits in the brain. Here, we report that when rats interact with a human caregiver who had recently undergone fear conditioning, they show risk assessment behavior and enhanced amygdala activation. The amygdala response involves its two major parts, the basolateral and central, which detect a threat and orchestrate defensive responses. Further, we show that humans who learn about a threat by observing another aversively aroused human, similar to rats, activate the basolateral and centromedial parts of the amygdala. Our results demonstrate that rats detect the emotional arousal of recently aversively stimulated caregivers and suggest that cross-species social transmission of threat information may involve similar neural circuits in the amygdala as the within-species transmission.


Assuntos
Núcleo Central da Amígdala , Humanos , Ratos , Animais , Medo/fisiologia , Aprendizagem , Nível de Alerta/fisiologia , Afeto
2.
J Neurosci ; 43(17): 3176-3185, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36963846

RESUMO

Prediction error (PE) is the mismatch between a prior expectation and reality, and it lies at the core of associative learning about aversive and appetitive stimuli. Human studies on fear learning have linked the amygdala to aversive PEs. In contrast, the relationship between the amygdala and PE in appetitive settings and stimuli, unlike those that induce fear, has received less research attention. Animal studies show that the amygdala is a functionally heterogeneous structure. Nevertheless, the role of the amygdala nuclei in PE signaling remains unknown in humans. To clarify the role of two subdivisions of the human amygdala, the centromedial amygdala (CMA) and basolateral amygdala (BLA), in appetitive and aversive PE signaling, we used gustatory pavlovian learning involving eating-related naturalistic outcomes. Thirty-eight right-handed individuals (19 females) participated in the study. We found that surprise with neutral feedback when a reward is expected triggers activity within the left and right CMA. When an aversive outcome is expected, surprise with neutral feedback triggers activity only within the left CMA. Notably, the BLA was not activated by those conditions. Thus, the CMA engages in negative PE signaling during appetitive and aversive gustatory pavlovian learning, whereas the BLA is not critical for this process. In addition, PE-related activity within the left CMA during aversive learning is negatively correlated with neuroticism and positively correlated with extraversion. The findings indicate the importance of the CMA in gustatory learning when the value of outcomes changes and have implications for understanding psychological conditions that manifest perturbed processing of negative PEs.SIGNIFICANCE STATEMENT A discrepancy between a prediction and an actual outcome (PE) plays a crucial role in learning. Learning improves when an outcome is more significant than expected (positive PE) and worsens when it is smaller than expected (negative PE). We found that the negative PE during appetitive and aversive taste learning is associated with increased activity of the CMA, which suggests that the CMA controls taste learning. Our findings may have implications for understanding psychological states associated with deficient learning from negative PEs, such as obesity and addictive behaviors.


Assuntos
Aprendizagem da Esquiva , Complexo Nuclear Basolateral da Amígdala , Animais , Feminino , Humanos , Tonsila do Cerebelo/diagnóstico por imagem , Condicionamento Clássico , Medo , Comportamento Apetitivo
3.
Addict Biol ; 29(2): e13364, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38380800

RESUMO

BACKGROUND: Alexithymia, difficulty in recognising and naming emotions, is common among people who use alcohol. There is also emerging evidence that people with alexithymia are unable to distinguish emotions from non-emotional physiological states. The project aimed to test if alcohol use is related to the way student drinkers experience emotions and physiological states in the body. METHODS: We employed a novel method to study bodily sensations related to emotions and physiological states in the context of alcohol use: the emBODY tool, which allowed participants to mark areas of the body in which they experience various emotions and physiological states. RESULTS: Students who showed a hazardous pattern of alcohol use (alcohol use disorders identification test [AUDIT] score ≥ 7, N = 91), overall, presented higher alexithymia levels and coloured larger areas for emotions and physiological states (showed less specificity) than those who show low-risk alcohol consumption (AUDIT ≤ 4, N = 90). Moreover, statistical classifiers distinguished feeling-specific maps less accurately for hazardous drinkers than low-risk drinkers [F(1,1998) = 441.16; p < 0.001], confirming that higher alcohol use is related to higher confusion of emotional and non-emotional bodily feelings. CONCLUSIONS: Plausibly, this increased bodily confusion drives alcohol consumption: alcohol may serve as a means of dealing with undifferentiated changes in psychophysiological arousal accompanying emotional states.


Assuntos
Alcoolismo , Humanos , Emoções/fisiologia , Sintomas Afetivos/psicologia , Consumo de Bebidas Alcoólicas , Estudantes/psicologia
4.
Neuroimage ; 251: 118889, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35065268

RESUMO

Current models of episodic memory posit that retrieval involves the reenactment of encoding processes. Recent evidence has shown that this reinstatement process - indexed by subsequent encoding-retrieval similarity of brain activity patterns - is related to the activity in the hippocampus during encoding. However, we tend to re-experience emotional events in memory more richly than dull events. The role of amygdala - a critical hub of emotion processing - in reinstatement of emotional events was poorly understood. To investigate it, we leveraged a previously overlooked divergence in the role of amygdala in memory modulation by distinct emotions - disgust and fear. Here we used a novel paradigm in which participants encoded complex events (word pairs) and their memory was tested after 3 weeks, both phases during fMRI scanning. Using representational similarity analysis and univariate analyses, we show that the strength of amygdala activation during encoding was correlated with memory reinstatement of individual event representations in emotion-specific regions. Critically, amygdala modulated reinstatement more for disgust than fear. This was in line with other differences observed at the level of memory performance and neural mechanisms of encoding. Specifically, amygdala and perirhinal cortex were more involved during encoding of disgust-related events, whereas hippocampus and parahippocampal gyrus during encoding of fear-related events. Together, these findings shed a new light on the role of the amygdala and medial temporal lobe regions in encoding and reinstatement of specific emotional memories.


Assuntos
Asco , Tonsila do Cerebelo/diagnóstico por imagem , Mapeamento Encefálico , Medo , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Lobo Temporal/fisiologia
5.
Neuroimage ; 263: 119648, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36162633

RESUMO

Humans often benefit from social cues when learning about the world. For instance, learning about threats from others can save the individual from dangerous first-hand experiences. Familiarity is believed to increase the effectiveness of social learning, but it is not clear whether it plays a role in learning about threats. Using functional magnetic resonance imaging, we undertook a naturalistic approach and investigated whether there was a difference between observational fear learning from friends and strangers. Participants (observers) witnessed either their friends or strangers (demonstrators) receiving aversive (shock) stimuli paired with colored squares (observational learning stage). Subsequently, participants watched the same squares, but without receiving any shocks (direct-expression stage). We observed a similar pattern of brain activity in both groups of observers. Regions related to threat responses (amygdala, anterior insula, anterior cingulate cortex) and social perception (fusiform gyrus, posterior superior temporal sulcus) were activated during the observational phase, possibly reflecting the emotional contagion process. The anterior insula and anterior cingulate cortex were also activated during the subsequent stage, indicating the expression of learned threat. Because there were no differences between participants observing friends and strangers, we argue that social threat learning is independent of the level of familiarity with the demonstrator.


Assuntos
Amigos , Imageamento por Ressonância Magnética , Humanos , Medo/fisiologia , Emoções , Tonsila do Cerebelo/fisiologia
6.
Brain Topogr ; 35(2): 219-231, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34775569

RESUMO

Stress may impact the ability to effectively regulate emotions. To study the impact of stressful experiences in early and recent life on emotion regulation, we examined the relationship between early life stress, recent stress, and brain activation during cognitive reappraisal. We investigated two regulation goals: the decrease and increase of emotional response to both negative and positive stimuli. Furthermore, two models of stress consequences were examined: the cumulative and match/mismatch models. A total of 83 participants (Mage = 21.66) took part in the study. There was an interaction between cumulative stress and stimuli valence in the cuneus, superior lateral occipital cortex, superior parietal lobule, supramarginal gyrus extending to superior temporal gyrus, and precentral gyrus extending to supplementary motor area. Interaction between mismatched stress index and stimuli valence was found in the left hippocampus, left insula extending to the orbitofrontal cortex and amygdala, and in a cluster including the anterior cingulate cortex, superior frontal gyrus, and frontal pole. Furthermore, there were differences between the effects of cumulative and mismatched stress indices on brain activation during reappraisal of positive but not negative stimuli. Results indicate that cumulative stress and match/mismatch approaches are both useful for explaining brain activation during reappraisal. This finding is important for our understanding of the multifaceted impact of stress on emotion regulation.


Assuntos
Regulação Emocional , Imageamento por Ressonância Magnética , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Emoções/fisiologia , Humanos , Estresse Psicológico/diagnóstico por imagem , Adulto Jovem
7.
Neuroimage ; 225: 117503, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33130273

RESUMO

Despite dissimilarities among scripts, a universal hallmark of literacy in skilled readers is the convergent brain activity for print and speech. Little is known, however, whether this differs as a function of grapheme to phoneme transparency in beginning readers. Here we compare speech and orthographic processing circuits in two contrasting languages, Polish and English, in 100 7-year-old children performing fMRI language localizer tasks. Results show limited language variation, with speech-print convergence evident mostly in left frontotemporal perisylvian regions. Correlational and intersect analyses revealed subtle differences in the strength of this coupling in several regions of interest. Specifically, speech-print convergence was higher for transparent Polish than opaque English in the right temporal area, associated with phonological processing. Conversely, speech-print convergence was higher for English than Polish in left fusiform, associated with visual word recognition. We conclude that speech-print convergence is a universal marker of reading even at the beginning of reading acquisition with minor variations that can be explained by the differences in grapheme to phoneme transparency. This finding at the earliest stages of reading acquisition conforms well with claims that reading exhibits a good deal of universality despite writing systems differences.


Assuntos
Encéfalo/diagnóstico por imagem , Idioma , Leitura , Percepção da Fala , Animais , Criança , Feminino , Lobo Frontal/diagnóstico por imagem , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Fonética , Lobo Temporal/diagnóstico por imagem
8.
J Child Psychol Psychiatry ; 59(1): 76-87, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28691732

RESUMO

BACKGROUND: Literacy acquisition is a demanding process that induces significant changes in the brain, especially in the spoken and written language networks. Nevertheless, large-scale paediatric fMRI studies are still limited. METHODS: We analyzed fMRI data to show how individual differences in reading performance correlate with brain activation for speech and print in 111 children attending kindergarten or first grade and examined group differences between a matched subset of emergent-readers and prereaders. RESULTS: Across the entire cohort, individual differences analysis revealed that reading skill was positively correlated with the magnitude of activation difference between words and symbol strings in left superior temporal, inferior frontal and fusiform gyri. Group comparisons of the matched subset of pre- and emergent-readers showed higher activity for emergent-readers in left inferior frontal, precentral, and postcentral gyri. Individual differences in activation for natural versus vocoded speech were also positively correlated with reading skill, primarily in the left temporal cortex. However, in contrast to studies on adult illiterates, group comparisons revealed higher activity in prereaders compared to readers in the frontal lobes. Print-speech coactivation was observed only in readers and individual differences analyses revealed a positive correlation between convergence and reading skill in the left superior temporal sulcus. CONCLUSIONS: These results emphasise that a child's brain undergoes several modifications to both visual and oral language systems in the process of learning to read. They also suggest that print-speech convergence is a hallmark of acquiring literacy.


Assuntos
Logro , Encéfalo/fisiologia , Imageamento por Ressonância Magnética/métodos , Leitura , Percepção da Fala/fisiologia , Mapeamento Encefálico/métodos , Criança , Feminino , Humanos , Masculino
9.
Neuroimage ; 132: 406-416, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26931814

RESUMO

Phonological processing ability is a key factor in reading acquisition, predicting its later success or causing reading problems when it is weakened. Our aim here was to establish the neural correlates of auditory word rhyming (a standard phonological measure) in 102 young children with (FHD+) and without familial history of dyslexia (FHD-) in a shallow orthography (i.e. Polish). Secondly, in order to gain a deeper understanding on how schooling shapes brain activity to phonological awareness, a comparison was made of children who had had formal literacy instruction for several months (in first grade) and those who had not yet had any formal instruction in literacy (in kindergarten). FHD+ children compared to FHD- children in the first grade scored lower in an early print task and showed longer reaction times in the in-scanner rhyme task. No behavioral differences between FHD+ and FHD- were found in the kindergarten group. On the neuronal level, overall familial risk was associated with reduced activation in the bilateral temporal, tempo-parietal and inferior temporal-occipital regions, as well as the bilateral inferior and middle frontal gyri. Subcortically, hypoactivation was found in the bilateral thalami, caudate, and right putamen in FHD+. A main effect of the children's grade was present only in the left inferior frontal gyrus, where reduced activation for rhyming was shown in first-graders. Several regions in the ventral occipital cortex, including the fusiform gyrus, and in the right middle frontal and postcentral gyri, displayed an interaction between familial risk and grade. The present results show strong influence of familial risk that may actually increase with formal literacy instruction.


Assuntos
Encéfalo/fisiologia , Dislexia/genética , Predisposição Genética para Doença , Fonética , Leitura , Mapeamento Encefálico , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudantes
10.
Behav Res Methods ; 47(4): 1222-1236, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25588892

RESUMO

In the present article, we introduce the Nencki Affective Word List (NAWL), created in order to provide researchers with a database of 2,902 Polish words, including nouns, verbs, and adjectives, with ratings of emotional valence, arousal, and imageability. Measures of several objective psycholinguistic features of the words (frequency, grammatical class, and number of letters) are also controlled. The database is a Polish adaptation of the Berlin Affective Word List-Reloaded (BAWL-R; Võ et al., Behavior Research Methods 41:534-538, 2009), commonly used to investigate the affective properties of German words. Affective normative ratings were collected from 266 Polish participants (136 women and 130 men). The emotional ratings and psycholinguistic indexes provided by NAWL can be used by researchers to better control the verbal materials they apply and to adjust them to specific experimental questions or issues of interest. The NAWL is freely accessible to the scientific community for noncommercial use as supplementary material to this article.


Assuntos
Afeto , Cultura , Idioma , Testes Neuropsicológicos/normas , Psicolinguística/normas , Adulto , Nível de Alerta , Emoções , Feminino , Alemanha , Humanos , Imaginação , Masculino , Pessoa de Meia-Idade , Polônia , Reprodutibilidade dos Testes , Caracteres Sexuais , Traduções , Adulto Jovem
11.
Int J Psychophysiol ; 192: 1-12, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37524120

RESUMO

Procrastination is an irrational delay of task completion. Previous studies have demonstrated that individuals who often procrastinate present deficits in attentional control and performance monitoring and that these dysfunctions might be differentially manifested depending on the motivational context. Building upon these results, the present event-related potential (ERP) study aimed to investigate the impact of norm-referenced feedback on executive functions among students with high (HP; N = 75) or low (LP; N = 77) procrastination levels. Participants completed the parametric Go/No-Go task, while receiving either positive or negative false feedback indicating how well they performed in comparison to others. The results indicated that positive (as opposed to negative) feedback led to higher self-reported arousal and increased post-error slowing in HP (vs. LP) participants. Moreover, neurophysiological measures indicated lower neural activation linked to attentional control (P300) and performance monitoring (ERN, CRN and Pe) in HP than LP participants, while the groups did not differ in these indices during the positive feedback condition. Obtained findings indicate that HP might be more sensitive to the motivating effects of success and more vulnerable to the detrimental influence of failure.


Assuntos
Atenção , Potenciais Evocados , Humanos , Atenção/fisiologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Motivação , Estudantes , Eletroencefalografia , Tempo de Reação/fisiologia
12.
Brain Imaging Behav ; 16(4): 1914-1918, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35266100

RESUMO

Cognitive-attentional syndrome (CAS) is in the self-regulatory executive function model a set of cognitive and behavioural strategies aimed at regulating cognition and emotion originating from maladaptive metacognitive beliefs. Investigating the brain structure of people with high levels of CAS enables a better understanding of the syndrome and bridging between the metacognitive model of psychopathology and previous results on structural abnormalities in various psychological disorders. Participants with high (n=40) and low levels of CAS (n=44) underwent structural Magnetic Resonance Imaging session. Voxel-Based Morphometry analytical approach was used to compute grey matter volume (GMV) differences between the groups. The group with a high level of CAS had lower GMV in the dorsal part of the anterior cingulate cortex. Our results are in line with the self-regulatory executive function model of psychopathology, showing a link between CAS and lowered GMV in the brain region associated with the regulation of cognition and emotion. They are also in agreement with meta-analytical results on structural correlates of various psychological disorders.


Assuntos
Imageamento por Ressonância Magnética , Metacognição , Atenção , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos
13.
J Exp Psychol Gen ; 151(8): 1942-1955, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34928685

RESUMO

Procrastination is a self-regulation failure in which people irrationally delay intended actions which leads to lower performance, satisfaction from achievements, and quality of life. Trait procrastination is estimated to affect 15% to 20% of the total population, and previous studies have shown procrastination to be related to impulsivity, emotion dysregulation, and executive dysfunctions, making it a good nonclinical example of a self-regulation disorder. Our previous fMRI results revealed impaired error processing (lower error-related activity of the anterior cingulate cortex) and lack of ability to intensify executive-control during the punishment context (no increase in activity in prefrontal regions) in procrastinators. This led us to the question of whether procrastination is related to impaired learning on errors and punishments. Low (LP) and high (HP) procrastinating students took part in a modified monetary probabilistic reversal learning task with separated reward and punishment conditions. Half of the participants started with reward and half with the punishment condition. Several learning models and model-free measures were applied to the collected behavioral data. Results suggest lower flexibility in the learning task in HP subjects, which can further decrease during the punishment condition. Moreover, HP subjects who began with the punishment condition tended to be less flexible throughout the rest of the task. These results suggest that impaired learning from errors and punishments may prevent highly procrastinating subjects from correcting their behaviors and add to the persistence of procrastination. We also conclude that impaired learning on errors and punishments might be a more general mechanism underpinning other self-regulation disorders. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Punição , Autocontrole , Humanos , Qualidade de Vida , Reversão de Aprendizagem/fisiologia , Recompensa
14.
Neuropsychologia ; 172: 108257, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35561814

RESUMO

Previous behavioural and neuroimaging studies have consistently reported that memory is enhanced for associations congruent or incongruent with the structure of prior knowledge, termed as schemas. However, it remains unclear if similar effects arise with emotion-related associations, and whether they depend on the type of emotions. Here, we addressed this question using a novel face-word pair association paradigm combined with fMRI and eye-tracking techniques. In two independent studies, we demonstrated and replicated that both congruency with emotion schemas and emotion category interact to affect associative memory. Overall, memory retrieval was higher for faces from pairs congruent vs. incongruent with emotion schemas, paralleled by a greater recruitment of left inferior frontal gyrus (IFG) during successful encoding. However, emotion schema effects differed across two negative emotion categories. Disgust was remembered better than fear, and only disgust activated left IFG stronger during encoding of congruent vs. incongruent pairs, suggestive of deeper semantic processing for the associations. On the contrary, encoding of congruent fear vs. disgust-related pairs was accompanied with greater activity in right fusiform gyrus (FG), suggesting a stronger sensory processing of faces. In addition, successful memory formation for congruent disgust pairs was associated with a higher pupil dilation index related to sympathetic activation, longer gaze time on words compared to faces, and more gaze switches between paired words and faces. This was reversed for fear-related congruent pairs where the faces attracted longer gaze time (compared to words). Overall, our results provide converging evidence from behavioural, physiological, and neural measures to suggest that congruency with available emotion schemas influence memory associations in a similar manner to semantic schemas. However, these effects vary across distinct emotion categories, pointing to a differential role of semantic processing and visual attention processes in the modulation of memory by disgust and fear, respectively.


Assuntos
Emoções , Memória , Asco , Emoções/fisiologia , Tecnologia de Rastreamento Ocular , Medo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Memória/fisiologia , Rememoração Mental/fisiologia
15.
J Psychiatr Res ; 151: 131-135, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35477077

RESUMO

Studies within the last decade have reported neural and behavioral differences in cognitive control between men with the pedophilic disorder who commit (CSO+) and do not commit (CSO-) child sexual abuse. Prior studies reported a higher number of errors in Go/Nogo task and lower activity of the prefrontal cortex in NoGo trials, in CSO+ compared with CSO-. Moreover, negative mood was reported as a risk factor for child sexual abuse in pedophilic men. We aimed to examine differences in brain function and behavior between CSO+ and CSO- patients regarding emotional interference on cognitive processes and inhibition. We recruited CSO+ (n = 11) and CSO- (n = 14) patients as well as matched healthy controls (HC) (n = 17). Participants performed the affective Go/NoGo task in a block-design functional magnetic resonance imaging experiment. The task comprised the following four conditions: Negative Go, including only Go stimuli and negatively valenced pictures; Negative NoGo, including 50% of Go and 50% of NoGo trials as well as negatively valenced pictures; and two corresponding conditions with neutral pictures. Brain analysis was restricted to the dorsolateral prefrontal (DLPFC), orbitofrontal, and anterior cingulate cortices. The HC and CSO- groups, but not the CSO+ group, showed significantly slower reactions in negative blocks compared with neutral blocks. Brain analysis revealed increased activation in the right DLPFC during emotional interference contrast (Negative > Neutral) in the HC and CSO- groups; however, there was decreased activation in the CSO+ group. In the CSO+ group, negative distractors did not increase cognitive control processes, which was observed in the CSO- and HC groups at the behavioral and neural levels. These results support previous reports indicating offender status is associated with cognitive and emotional impairments.


Assuntos
Abuso Sexual na Infância , Criminosos , Criança , Abuso Sexual na Infância/psicologia , Cognição/fisiologia , Córtex Pré-Frontal Dorsolateral , Emoções/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem
16.
J Neurosci ; 30(9): 3199-209, 2010 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-20203179

RESUMO

Visually responding neurons in the superficial, retinorecipient layers of the cat superior colliculus receive input from two primarily parallel information processing channels, Y and W, which is reflected in their velocity response profiles. We quantified the time-dependent variability of responses of these neurons to stimuli moving with different velocities by Fano factor (FF) calculated in discrete time windows. The FF for cells responding to low-velocity stimuli, thus receiving W inputs, increased with the increase in the firing rate. In contrast, the dynamics of activity of the cells responding to fast moving stimuli, processed by Y pathway, correlated negatively with FF whether the response was excitatory or suppressive. These observations were tested against several types of surrogate data. Whereas Poisson description failed to reproduce the variability of all collicular responses, the inclusion of secondary structure to the generating point process recovered most of the observed features of responses to fast moving stimuli. Neither model could reproduce the variability of low-velocity responses, which suggests that, in this case, more complex time dependencies need to be taken into account. Our results indicate that Y and W channels may differ in reliability of responses to visual stimulation. Apart from previously reported morphological and physiological differences of the cells belonging to Y and W channels, this is a new feature distinguishing these two pathways.


Assuntos
Percepção de Movimento/fisiologia , Neurônios/fisiologia , Células Ganglionares da Retina/fisiologia , Colículos Superiores/fisiologia , Campos Visuais/fisiologia , Vias Visuais/fisiologia , Potenciais de Ação/fisiologia , Animais , Gatos , Simulação por Computador , Eletrofisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Potenciais Pós-Sinápticos Inibidores/fisiologia , Masculino , Testes Neuropsicológicos , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Distribuição de Poisson , Tempo de Reação/fisiologia , Processamento de Sinais Assistido por Computador , Transmissão Sináptica/fisiologia , Fatores de Tempo
17.
Acta Neurobiol Exp (Wars) ; 81(2): 111-120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34170259

RESUMO

Here we examine how exposure to blue (peaking at λ=470 nm), green (peaking at λ=505 nm) and red (peaking at λ=630 nm) light affects subsequent working memory performance measured with visual N-back tasks and associated functional brain responses in participants with extreme morning and extreme evening chronotype. We used within-subjects experimental manipulation on carefully selected samples and state of the art equipment for light exposure. The results show no differences between extreme morning-type and evening-type individuals in N-back task performance. We also did not replicate the alerting effect of exposure to blue wavelength light, supposedly enhancing performance on cognitive tasks. However, we found higher brain activity in the morning hours for extreme morning in comparison to extreme evening chronotype in several frontal areas of the precentral gyrus, middle and superior frontal gyri and in the occipital gyrus. This may indicate increased strategic or attentional recruitment of prefrontal areas, implicated in compensating working memory load in the morning type.


Assuntos
Encéfalo/fisiologia , Ritmo Circadiano/fisiologia , Cognição/fisiologia , Luz , Memória de Curto Prazo/fisiologia , Atenção/fisiologia , Humanos , Córtex Pré-Frontal/fisiologia , Desempenho Psicomotor/fisiologia
18.
Front Psychiatry ; 11: 609874, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33574773

RESUMO

Self-regulation (SR) is an important human function that relates to quality of life in multiple domains including mental health. Previous studies have found important correlates of low SR including impulsivity and poor emotional regulation; however, underpinnings of low SR are incompletely understood. Individuals low in SR frequently engage in maladaptive behaviors (substance abuse, procrastination, etc.) despite negative consequences. This phenomenon suggests that impaired learning from errors and punishments may be important mechanisms underlying low SR. Consistently, previous studies observed impaired error processing in a wide spectrum of individuals with low SR and impaired learning from errors and punishments in SR-related disorders. We also note a possible role for poor emotional regulation and refer to concepts suggesting that engaging in maladaptive behaviors may serve as short term emotion regulation strategies aimed at avoiding or alleviating negative affect. We speculate on transdiagnostic factors underlying poor SR. We propose that impaired error processing (possibly related to striatal functioning) may prevent subjects with low SR from learning from errors and punishments and thus learning better SR skills or tendencies. Additionally, impaired coping in emotionally challenging situations, possibly related to prefrontal-cortical functioning, may lead to maladaptive avoidance. Moreover, maladaptive behaviors may be reinforced by the temporary decreases in negative affect and rewarding values of behaviors. Given existing knowledge gaps, we call for more extensive research and describe possible directions and challenges for future studies.

19.
Behav Res Ther ; 132: 103693, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32688045

RESUMO

OBJECTIVE: Attention Training Technique (ATT) is a key therapeutic tool in metacognitive therapy. There are numerous studies on the behavioral effects of ATT, however the neural mechanisms at work in the training are yet to be uncovered. To date there have been no controlled fMRI studies of ATT. METHOD: We conducted a randomized double-blind controlled study of two groups with varying levels of cognitive-attentional syndrome (CAS). Groups with high (n = 43) and low (n = 46) levels of CAS underwent a single session of ATT or a control condition (CON) in an MRI scanner. Participants underwent resting state functional MRI (rsfMRI) sessions and rumination induction sessions both pre- and post-intervention Functional connectivity analyses and inter-subject correlations analyses were computed. We also collected data on emotion and attention functioning pre- and post-intervention. RESULTS: We did not observe any behavioral effects of ATT. However, direct comparison between ATT and CON sessions revealed greater inter-subject correlations in almost all hubs belonging to the studied functional networks. Moreover, subjects who received ATT showed diminished connectivity in the fronto-parietal network during ruminations and diminished connectivity of the precuneus with lateral occipital cortices and the intraparietal sulcus in abstract thinking and rsfMRI, respectively. Furthermore, some of the observed effects in functional connectivity and inter-subject correlations were specific to different levels of CAS. CONCLUSIONS: Our results may support a proposed neural mechanism for ATT: disengagement of attention from CAS-type processing in either low- or high-CAS individuals. It is also possible that some neural effects of ATT are specific to individuals with different levels of CAS.

20.
Front Aging Neurosci ; 12: 194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32848698

RESUMO

Working memory (WM) is a limited-capacity cognitive system that allows the storage and use of a limited amount of information for a short period of time. Two WM processes can be distinguished: maintenance (i.e., storing, monitoring, and matching information) and manipulation (i.e., reordering and updating information). A number of studies have reported an age-related decline in WM, but the mechanisms underlying this deterioration need to be investigated. Previous research, including studies conducted in our laboratory, revealed that age-related cognitive deficits are related to decreased millisecond timing, i.e., the ability to perceive and organize incoming events in time. The aim of the current study was: (1) to identify in the elderly the brain network involved in the maintenance and manipulation WM processes; and (2) to use an fMRI task to investigate the relation between the brain activity associated with these two processes and the efficiency of temporal information processing (TIP) on a millisecond level reflected by psychophysical indices. Subjects were 41 normal healthy elderly people aged from 62 to 78 years. They performed: (1) an auditory verbal n-back task for assessing WM efficiency in an MRI scanner; and (2) a psychophysical auditory temporal-order judgment (TOJ) task for assessing temporal resolution in the millisecond domain outside the scanner. The n-back task comprised three conditions (0-, 1-, and 2-back), which allowed maintenance (1- vs. 0-back comparisons) and manipulation (2- vs. 1-back comparisons) processes to be distinguished. Results revealed the involvement of a similar brain network in the elderly to that found in previous studies. However, during maintenance processes, we found relatively limited and focused activations, which were significantly extended during manipulation. A novel result of our study, never reported before, is an indication of significant moderate correlations between the efficiency of WM and TIP. These correlations were found only for manipulation but not for maintenance. Our results confirmed the hypothesis that manipulation in the elderly is a dynamic process requiring skilled millisecond timing with high temporal resolution. We conclude that millisecond timing contributes to WM manipulation in the elderly, but not to maintenance.

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