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1.
Brain Topogr ; 35(5-6): 599-612, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35933532

RESUMO

Previous research shows that dynamic stimuli, on the one hand, and emotional stimuli, on the other, capture exogenous attention due to their biological relevance. Through neural (ERPs) and behavioral measures (reaction times and errors), the present study explored the combined effect of looming motion and emotional content on attentional capture. To this end, 3D-recreated static and dynamic animals assessed as emotional (positive or negative) or neutral were presented as distractors while 71 volunteers performed a line orientation task. We observed a two-phase effect: firstly (before 300 ms), early components of ERPs (P1p and N2po) showed enhanced exogenous attentional capture by looming positive distractors and static threatening animals. Thereafter, dynamic and static threatening distractors received enhanced endogenous attention as revealed by both late ERP activity (LPC) and behavioral (errors) responses. These effects are likely explained by both the emotional valence and the distance of the stimulus at each moment.


Assuntos
Emoções , Potenciais Evocados , Estimulação Luminosa , Emoções/fisiologia , Potenciais Evocados/fisiologia , Tempo de Reação/fisiologia , Eletroencefalografia
2.
Psychol Sci ; 32(1): 120-131, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33301363

RESUMO

Evaluative conditioning is one of the most widely studied procedures for establishing and changing attitudes. The surveillance task is a highly cited evaluative-conditioning paradigm and one that is claimed to generate attitudes without awareness. The potential for evaluative-conditioning effects to occur without awareness continues to fuel conceptual, theoretical, and applied developments. Yet few published studies have used this task, and most are characterized by small samples and small effect sizes. We conducted a high-powered (N = 1,478 adult participants), preregistered close replication of the original surveillance-task study (Olson & Fazio, 2001). We obtained evidence for a small evaluative-conditioning effect when "aware" participants were excluded using the original criterion-therefore replicating the original effect. However, no such effect emerged when three other awareness criteria were used. We suggest that there is a need for caution when using evidence from the surveillance-task effect to make theoretical and practical claims about "unaware" evaluative-conditioning effects.


Assuntos
Conscientização , Condicionamento Psicológico , Adulto , Atitude , Condicionamento Clássico , Humanos , Processos Mentais
3.
Hum Brain Mapp ; 41(7): 1711-1724, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31860166

RESUMO

Scarce previous data on how the location where an emotional stimulus appears in the visual scene modulates its perception suggest that, for functional reasons, a perceptual advantage may exist, vertically, for stimuli presented at the lower visual field (LoVF) and, horizontally, for stimuli presented at the left visual field (LeVF). However, this issue has been explored through a limited number of spatial locations, usually in a single spatial dimension (e.g., horizontal) and invariant eccentricities. Event-related potentials (ERPs) were recorded from 39 participants perceiving brief neutral (wheels) and emotional stimuli (spiders) presented at 17 different locations, one foveal and 16 at different peripheral coordinates. As a secondary scope, we explored the role of the magnocellular (M) and the parvocellular (P) visual pathways by presenting an isoluminant/heterochromatic (P-biased) and a heteroluminant/isochromatic version (M-biased) of each stimulus. Emo > Neu effects were observed in PN1 (120 ms) for stimuli located at fovea, and in PN2 (215 ms) for stimuli located both at fovea and diverse peripheral regions. A factorial approach to these effects further revealed that: (a) emotional stimuli presented in the periphery are efficiently perceived, without evident decrease from para- to perifovea; (b) peripheral Emo > Neu effects are reflected 95 ms later than foveal Emo > Neu effects in ERPs; (c) LoVF is more involved than UVF in these effects; (d) our data fail to support the LeVF advantage previously reported, and (e) Emo > Neu effects were significant for both M and P stimuli.


Assuntos
Emoções/fisiologia , Potenciais Evocados/fisiologia , Retina/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Fóvea Central/diagnóstico por imagem , Fóvea Central/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Campos Visuais , Vias Visuais/diagnóstico por imagem , Vias Visuais/fisiologia , Adulto Jovem
4.
J Neurosci ; 38(38): 8262-8276, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30104342

RESUMO

In fear conditioning, more efficient sensory processing of a stimulus (the conditioned stimulus, CS) that has acquired motivational relevance by being paired with an aversive event (the unconditioned stimulus, US) has been associated with increased cortical gain in early sensory brain areas (Miskovic and Keil, 2012). Further, this sensory gain modulation related to short-term plasticity changes occurs independently of aware cognitive anticipation of the aversive US, pointing toward implicit learning mechanisms (Moratti and Keil, 2009). However, it is unknown how quickly the implicit learning of CS-US associations results in the adaptation of cortical gain. Here, using steady-state visually evoked fields derived from human Magnetoencephalography (MEG) recordings in two experiments (N = 33, 17 females and 16 males), we show that stimulus-driven neuromagnetic oscillatory activity increases and decreases quickly as a function of associative strength within three or four trials, as predicted by a computationally implemented Rescorla-Wagner model with the highest learning rate. These ultrafast cortical gain adaptations are restricted to early visual cortex using a delay fear conditioning procedure. Short interval (500 ms) trace conditioning resulted in the same ultrafast activity modulations by associative strength, but in a complex occipito-parieto-temporo-frontal network. Granger causal analysis revealed that reverberating top-down and bottom-up influences between anterior and posterior brain regions during trace conditioning characterized this network. Critically, in both delay and trace conditioning, ultrafast cortical gain modulations as a function of associative strength occurred independently of conscious US anticipation.SIGNIFICANCE STATEMENT In ever-changing environments, learned associations between a cue and an aversive consequence must change under new stimulus-consequence contingencies to be adaptive. What predicts potential dangers now might be meaningless in the next situation. Predictive cues are prioritized, as reflected by increased sensory cortex activity for these cues. However, this modulation also must adapt to altered stimulus-consequence contingencies. Here, we show that human visual cortex activity can be modulated quickly according to ultrafast contingency changes within a few learning trials. This finding extends to frontal brain regions when the cue and the aversive event are separated in time. Critically, this ultrafast updating process occurs orthogonally to aware aversive outcome anticipation and therefore relies on unconscious implicit learning mechanisms.


Assuntos
Aprendizagem por Associação/fisiologia , Encéfalo/fisiologia , Condicionamento Clássico/fisiologia , Medo/fisiologia , Adulto , Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Magnetoencefalografia , Masculino , Adulto Jovem
5.
J Cogn Neurosci ; 29(10): 1699-1711, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28557693

RESUMO

Exogenous attention is a set of mechanisms that allow us to detect and reorient toward salient events-such as appetitive or aversive-that appear out of the current focus of attention. The nature of these mechanisms, particularly the involvement of the parvocellular and magnocellular visual processing systems, was explored. Thirty-four participants performed a demanding digit categorization task while salient (spiders or S) and neutral (wheels or W) stimuli were presented as distractors under two figure-ground formats: heterochromatic/isoluminant (exclusively processed by the parvocellular system, Par trials) and isochromatic/heteroluminant (preferentially processed by the magnocellular system, Mag trials). This resulted in four conditions: SPar, SMag, WPar, and WMag. Behavioral (RTs and error rates in the task) and electrophysiological (ERPs) indices of exogenous attention were analyzed. Behavior showed greater attentional capture by SMag than by SPar distractors and enhanced modulation of SMag capture as fear of spiders reported by participants increased. ERPs reflected a sequence from magnocellular dominant (P1p, ≃120 msec) to both magnocellular and parvocellular processing (N2p and P2a, ≃200 msec). Importantly, amplitudes in one N2p subcomponent were greater to SMag than to SPar and WMag distractors, indicating greater magnocellular sensitivity to saliency. Taking together, results support a magnocellular bias in exogenous attention toward distractors of any nature during initial processing, a bias that remains in later stages when biologically salient distractors are present.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Medo/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa/métodos , Tempo de Reação , Adulto Jovem
6.
Atten Percept Psychophys ; 85(3): 796-813, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36417127

RESUMO

The additional singleton task has become a popular paradigm to explore visual statistical learning and selective attention. In this task, participants are instructed to find a different-shaped target among a series of distractors as fast as possible. In some trials, the search display includes a singleton distractor with a different color, making search more difficult. This singleton distractor appears more often in one location than in the remaining locations. The typical results of these experiments show that participants learn to ignore the area of the screen that is more likely to contain the singleton distractor. It is often claimed that this learning takes place unconsciously, because at the end of the experiment participants seem to be unable to identify the location where the singleton distractor appeared most frequently during the task. In the present study, we tested participants' awareness in three high-powered experiments using alternative measures. Contrary to previous studies, the results show clear evidence of explicit knowledge about which area of the display was more likely to contain the singleton distractor, suggesting that this type of learning might not be unconscious.


Assuntos
Atenção , Aprendizagem Espacial , Humanos , Tempo de Reação
7.
J Exp Psychol Learn Mem Cogn ; 49(7): 1019-1032, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36326649

RESUMO

In a typical probabilistic cuing experiment, participants are asked to find a visual target among a series of distractors. Although participants are not informed about this, the target appears more frequently in one region of the display, resulting in faster search times for targets located in this region. This bias is thought to depend on a habit-like attentional control mechanism, unconstrained by the availability of working memory (WM) resources. However, the only study that has explored this feature in the past suffers from methodological shortcomings that leave the results open to alternative explanations. In three experiments, we aimed to confirm whether probabilistic cuing is unaffected by visual, spatial, and spatiotemporal WM load. For each experiment, one group of participants performed the visual search task during the retention interval of a WM task (high-load group), whereas another group of participants (no-load group) carried out the visual search task after the WM task. We hypothesized that the probabilistic cuing effect would be larger for the no-load group compared to the high-load group. This hypothesis was confirmed in one experiment, but exploratory analyses suggest that the results can be highly dependent on the analytic approach, casting doubts on its robustness. Overall, our results provide partial support for the hypothesis that probabilistic cuing is not affected by a secondary task. However, given that some analyses reveal an effect of WM load, we conclude that it might be premature to rule out the possibility that the expression of this attentional bias requires WM resources. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Sinais (Psicologia) , Memória de Curto Prazo , Humanos , Atenção , Emoções
8.
Psychon Bull Rev ; 29(2): 521-529, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34816390

RESUMO

In studies on probabilistic cuing of visual search, participants search for a target among several distractors and report some feature of the target. In a biased stage the target appears more frequently in one specific area of the search display. Eventually, participants become faster at finding the target in that rich region compared to the sparse region. In some experiments, this stage is followed by an unbiased stage, where the target is evenly located across all regions of the display. Despite this change in the spatial distribution of targets, search speed usually remains faster when the target is located in the previously rich region. The persistence of the bias even when it is no longer advantageous has been taken as evidence that this phenomenon is an attentional habit. The aim of this meta-analysis was to test whether the magnitude of probabilistic cuing decreases from the biased to the unbiased stage. A meta-analysis of 42 studies confirmed that probabilistic cuing during the unbiased stage was roughly half the size of cuing during the biased stage, and this decrease persisted even after correcting for publication bias. Thus, the evidence supporting the claim that probabilistic cuing is an attentional habit might not be as compelling as previously thought.


Assuntos
Sinais (Psicologia) , Percepção Espacial , Atenção , Hábitos , Humanos , Tempo de Reação
9.
Cortex ; 154: 287-298, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35816850

RESUMO

It is usually easier to find objects in familiar contexts that we have seen before. The type of learning that underlies this facilitation, known as contextual cueing, has been understood as an incidental and automatic process given that, among other reasons, it seems to be independent of working memory (WM) resources. This claim has found support in previous research showing that contextual cueing can be acquired latently, while participants perform a demanding WM task. However, previous studies have not always found this pattern of results and, in general, the available evidence is far from conclusive. The aim of the present study was to clarify the role of WM in contextual learning with two large-sample, confirmatory experiments. Our results show a robust contextual cueing effect even when visuospatial working memory resources were recruited by a demanding secondary task.


Assuntos
Sinais (Psicologia) , Memória de Curto Prazo , Humanos , Aprendizagem , Tempo de Reação
10.
Soc Neurosci ; 16(1): 39-56, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32698660

RESUMO

Cacioppo and colleagues advanced the study of anthropomorphism by positing three motives that moderated the occurrence of this phenomenon; belonging, effectance, and explanation. Here, we further this literature by exploring the extent to which the valence of a target's behavior influences its anthropomorphism when perceivers attempt to explain and predict that target's behavior, and the involvement of brain regions associated with explanation and prediction in such anthropomorphism. Participants viewed videos of varying visually complex agents - geometric shapes, computer generated (CG) faces, and greebles - in nonrandom motion performing harming and helping behaviors. Across two studies, participants reported a narrative that explained the observed behavior (both studies) while we recorded brain activity (study one), and participants predicted future behavior of the protagonist shapes (study two). Brain regions implicated in prediction error (striatum), not language generation (inferior frontal gyrus; IFG) engaged more to harming than helping behaviors during the anthropomorphism of such stimuli. Behaviorally, we found greater anthropomorphism in explanations of harming rather than helping behaviors, but the opposite pattern when participants predicted the agents' behavior. Together, these studies build upon the anthropomorphism literature by exploring how the valence of behavior drives explanation and prediction.


Assuntos
Comportamento de Ajuda , Motivação , Encéfalo , Computadores , Humanos
11.
Psychophysiology ; 58(5): e13795, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33604885

RESUMO

Reward affects our attention to stimuli, prioritizing those that lead to high-value outcomes. Recently, it has been suggested that such reward-related cognitive prioritization might be associated with the process of learning new stimulus-response (S-R) associations, because both are acquired through extended reward training, and once established, they are hard to overcome. We used event-related potentials (ERP) to analyze the contribution of S-R links to the formation of reward-related cognitive prioritization during reinforcement learning. Reward-related cognitive prioritization was measured by comparing the ERP signals for stimuli predicting high-value and low-value outcomes. In addition, we compared a strong S-R link (same stimulus, same response), with a weak S-R link condition (same stimulus, two different responses). The participants' performance was more accurate and faster when the procedure allowed for establishing strong S-R links and for high-value outcomes. Furthermore, those stimuli associated with strong S-R links showed a larger P3 amplitude at parietal sites. Value effects (larger ERP activity for those stimuli predicting a high-value outcome) were obtained at parietal and occipital sites in the P3 time window. However, value effects did not benefit from strong S-R links in either the P1 or the P3 components. These results suggest that strong S-R learning is not necessary to develop reward-related modulations of ERP activity.


Assuntos
Cognição/fisiologia , Potenciais Evocados/fisiologia , Reforço Psicológico , Adolescente , Adulto , Variação Contingente Negativa , Feminino , Humanos , Aprendizagem/fisiologia , Masculino , Pessoa de Meia-Idade , Desempenho Psicomotor , Recompensa , Adulto Jovem
12.
J Exp Psychol Hum Percept Perform ; 47(1): 116-120, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33180547

RESUMO

It is usually easier to find objects in a visual scene as we gain familiarity with it. Two decades of research on contextual cuing of visual search show that repeated exposure to a search display can facilitate the detection of targets that appear at predictable locations in that display. Typical accounts for this effect attribute an essential role to learned associations between the target and other stimuli in the search display. These associations improve visual search either by driving attention toward the usual location of the target or by facilitating its recognition. Contrary to this view, we show that a robust contextual cuing effect can also be observed when repeated search displays do not allow the location of the target to be predicted. These results suggest that, in addition to the mechanisms already explored by previous research, participants learn to ignore the locations usually occupied by distractors, which in turn facilitates the detection of targets even when they appear in unpredictable locations. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Atenção , Sinais (Psicologia) , Humanos , Aprendizagem , Reconhecimento Visual de Modelos , Reconhecimento Psicológico
13.
Psychophysiology ; 58(5): e13785, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33550631

RESUMO

Previous research shows that endogenous attention (the controlled selection of certain aspects of our environment) is enhanced toward emotional stimuli due to its biological relevance. Although looming affective stimuli such as threat seem even more critical for survival, little is known about their effect on endogenous attention. Here, we recorded neural (event-related potentials, ERPs) and behavioral responses (errors and reaction times) to explore the combined effect of emotion and looming motion. 3D-recreated static and moving animals assessed as emotionally positive, negative, and neutral, were presented to participants (n = 71), who performed an indirect categorization task (vertebrate vs. invertebrate). Behavioral results showed better task performance, as reflected by lower number of errors and reaction times, in response to threatening stimuli. Neural indices revealed significant early (P1p, 150 milliseconds), intermediate (P2p, 240), and late (LPP, 450) effects, the latter being more intensely associated with behavior, as revealed by regression analyses. In general, neural indexes of attention to both static and dynamic stimuli showed a positivity offset in early stages and a negativity bias in subsequent phases. However, and importantly, the progressive inclusion of negative stimuli in the attentional focus is produced earlier in the case of dynamic (at P2p latency) than in static versions (at LPP). These results point to an enhancement of attention, particularly in temporal terms, toward stimuli combining motion and biological significance.


Assuntos
Atenção/fisiologia , Emoções , Potenciais Evocados/fisiologia , Percepção de Movimento , Estimulação Luminosa/métodos , Percepção Visual , Adolescente , Adulto , Feminino , Humanos , Masculino , Tempo de Reação , Adulto Jovem
14.
Soc Neurosci ; 16(3): 252-264, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33567227

RESUMO

Habituation to ethnic ingroup members has been reported to be greater than to ethnic outgroup members. This pattern could be due to the lack of perceptive experience (familiarity) with outgroup facial morphs or, alternatively, to the prejudice held toward that outgroup. We explored this disjunctive in 71 participants, all Spanish, who were experimentally habituated to faces from their Ingroup and to faces from two unfamiliar outgroups, one for which there is low probability of prejudice in this population (Non-prejudiced Outgroup), and one for which the probability of prejudice is higher (Prejudiced Outgroup). We indexed habituation through event-related potentials, concretely as the differential amplitude of the face-sensitive N170 component from Initial to Final trials of each group. Afterward, participants completed several prejudice measures. N170 showed significant habituation to all faces, though it did not differ among groups. However, a regression analysis revealed that individual habituation to the Outgroup faces was inversely related to implicit prejudice scores. Importantly, N170 amplitudes were maximal for the Prejudiced Outgroup in both Initial and Final trials. We conclude that these effects are explained by the prejudice held toward a specific outgroup rather than perceptive experience.


Assuntos
Potenciais Evocados , Preconceito , Etnicidade , Humanos , Reconhecimento Psicológico
15.
J Exp Psychol Hum Percept Perform ; 46(10): 1222-1234, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32757593

RESUMO

In probabilistic cuing of visual search, participants search for a target object that appears more frequently in one region of the display. This task results in a search bias toward the rich quadrant compared with other quadrants. Previous research has suggested that this bias is inflexible (difficult to unlearn) and implicit (participants are unaware of the biased distribution of targets). We tested these hypotheses in two preregistered, high-powered experiments (Ns = 160 and 161). In an initial biased stage, participants performed a standard probabilistic cuing task. In a subsequent unbiased stage, the target appeared in all quadrants with equal probability. Awareness questions were included after the biased stage in one group of participants, and after the unbiased stage in a second group. Results showed that participants were aware of the rich area, and this effect was larger for the group whose awareness was assessed after the biased stage. In addition, analyses of visual search times indicated that the search bias toward the rich area (formed during the biased stage) was reduced during the unbiased stage. These results cast doubts on the characterization of probabilistic cuing as an implicit and inflexible search habit. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Conscientização/fisiologia , Sinais (Psicologia) , Aprendizagem por Probabilidade , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
16.
Psychon Bull Rev ; 27(3): 512-519, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32162205

RESUMO

People usually become faster at finding a visual target after repeated exposure to the same search display. This effect, known as contextual cueing, is often thought to rely on a highly efficient learning mechanism, relatively unconstrained by the availability of attentional resources. Consistent with this view, experimental evidence suggests that contextual cueing can be found even when participants are instructed to ignore the repeated visual context, although this learning remains latent until the context receives full attention. The present study explores the contribution of selective attention to contextual cueing in four high-powered preregistered experiments. None of them supported the hypothesis that latent learning can occur without selective attention. In general, our results suggest that selective attention to visual context plays an essential role in both the acquisition and the expression of contextual cueing.


Assuntos
Atenção/fisiologia , Sinais (Psicologia) , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
17.
Soc Cogn Affect Neurosci ; 15(6): 615-624, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32588901

RESUMO

Exogenous attention allows the automatic detection of relevant stimuli and the reorientation of our current focus of attention towards them. Faces from an ethnic outgroup tend to capture exogenous attention to a greater extent than faces from an ethnic ingroup. We explored whether prejudice toward the outgroup, rather than lack of familiarity, is driving this effect. Participants (N = 76) performed a digit categorization task while distractor faces were presented. Faces belonged to (i) a prejudiced outgroup, (ii) a non-prejudiced outgroup and (iii) their ingroup. Half of the faces were previously habituated in order to increase their familiarity. Reaction times, accuracy and event-related potentials (ERPs) were recorded to index exogenous attention to distractor faces. Additionally, different indexes of explicit and implicit prejudice were measured, the latter being significantly greater towards prejudiced outgroup. N170 amplitude was greater to prejudiced outgroup-regardless of their habituation status-than to both non-prejudiced outgroup and ingroup faces and was associated with implicit prejudice measures. No effects were observed at the behavioral level. Our results show that implicit prejudice, rather than familiarity, is under the observed attention-related N170 effects and that this ERP component may be more sensitive to prejudice than behavioral measures under certain circumstances.


Assuntos
Atenção/fisiologia , Potenciais Evocados/fisiologia , Preconceito , Reconhecimento Psicológico/fisiologia , Adolescente , Adulto , Encéfalo/fisiologia , Etnicidade , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Adulto Jovem
18.
Psychophysiology ; 54(6): 882-893, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28169431

RESUMO

In unpredictable environments, stimuli that predict potential danger or its absence can change rapidly. Therefore, it is highly adaptive to prioritize incoming sensory information flexibly as a function of prior experience. Previously, these changes have only been conceptualized as excitatory gain increases in sensory cortices for acquired fear-relevant stimuli during associative learning. However, formal descriptions of associative processes by Rescorla and Wagner predict both conditioned excitatory and inhibitory processes in response systems for fear and safety cues, respectively. Magnetocortical steady-state visual evoked fields (ssVEFs) have been shown to vary in amplitude as a function of associative strength. Therefore, we wondered why previous studies reporting ssVEF modulations by fear learning did not observe conditioned inhibition of ssVEF responses for the safety cue. Three analysis strategies were applied: (1) traditional analysis of ssVEF amplitude at occipital MEG sensors, (2) applying a general linear model (GLM) at each sensor, and (3) fitting the same GLM to cortically localized ssVEF responses. First, we replicated previous findings of increased ssVEFs for acquired fear-relevant stimuli using all three analysis strategies. Critically, we demonstrated conditioned inhibition of ssVEF responses for fear-irrelevant cues for specific gradiometer sensor types using the traditional analysis technique and for all sensor types when applying a GLM to the sensor space. However, sensor space effects were rather small. In stark contrast, cortical source space effect sizes were most pronounced. The results of opposing CS+ and CS- modulations in sensory cortex reflect predictions of the Rescorla-Wagner model and current neurobiological findings.


Assuntos
Encéfalo/fisiologia , Condicionamento Clássico/fisiologia , Inibição Neural/fisiologia , Córtex Visual/fisiologia , Adulto , Mapeamento Encefálico , Medo/fisiologia , Feminino , Resposta Galvânica da Pele/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa
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