Search results for "Stimulus"

Magnetoencephalography Responses to Unpredictable and Predictable Rare Somatosensory Stimuli in Healthy Adult Humans

2021

Mismatch brain responses to unpredicted rare stimuli are suggested to be a neural indicator of prediction error, but this has rarely been studied in the somatosensory modality. Here, we investigated how the brain responds to unpredictable and predictable rare events. Magnetoencephalography responses were measured in adults frequently presented with somatosensory stimuli (FRE) that were occasionally replaced by two consecutively presented rare stimuli [unpredictable rare stimulus (UR) and predictable rare stimulus (PR); p = 0.1 for each]. The FRE and PR were electrical stimulations administered to either the little finger or the forefinger in a counterbalanced manner between the two conditio…

Attentional bias towards interpersonal aggression in depression – an eye movement study

2020

Depressed individuals exhibit an attentional bias towards mood-congruent stimuli, yet evidence for biased processing of threat-related information in human interaction remains scarce. Here, we tested whether an attentional bias towards interpersonally aggressive pictures over interpersonally neutral pictures could be observed to a greater extent in depressed participants than in control participants. Eye movements were recorded while the participants freely viewed visually matched interpersonally aggressive and neutral pictures, which were presented in pairs. Across the groups, participants spent more time looking at neutral pictures than at aggressive pictures, probably reflecting avoidanc…

2020

A habit is a regularity in automatic responding to a specific situation. Classical learning psychology explains the emergence of habits by an extended learning history during which the response becomes associated to the situation (learning of stimulus-response associations) as a function of practice ("law of exercise") and/or reinforcement ("law of effect"). In this paper, we propose the "law of recency" as another route to habit acquisition that draws on episodic memory models of automatic response regulation. According to this account, habitual responding results from (a) storing stimulus-response episodes in memory, and (b) retrieving these episodes when encountering the stimulus again. …

2017

Some years ago Cheung et al. (2008) proposed the complete design (CD) for measuring the failure of selective attention in composite objects. Since the CD is a fully balanced design, analysis of response bias may reveal potential effects of the experimental manipulation, the stimulus material, and/or attributes of the observers. Here we used the CD to prove whether external features modulate perception of internal features with the context congruency paradigm (Nachson et al., 1995; Meinhardt-Injac et al., 2010) in a larger sample of N = 303 subjects. We found a large congruency effect (Cohen's d = 1.78), which was attenuated by face inversion (d = 1.32). The congruency relation also strongly…

2014

Some years ago an improved design (the "complete design") was proposed to assess the composite face effect in terms of a congruency effect, defined as the performance difference for congruent and incongruent target to no-target relationships (Cheung et al., 2008). In a recent paper Rossion(2013) questioned whether the congruency effect was a valid hallmark of perceptual integration, because it may contain confounds with face-unspecific interference effects. Here we argue that the complete design is well-balanced and allows one to separate face-specific from face-unspecific effects. We used the complete design for a same/different composite stimulus matching task with face and non-face objec…

Automatic auditory intelligence: an expression of the sensory-cognitive core of cognitive processes.

2010

Abstract In this article, we present a new view on the nature of cognitive processes suggesting that there is a common core, viz., automatic sensory–cognitive processes that form the basis for higher-order cognitive processes. It has been shown that automatic sensory–cognitive processes are shared by humans and various other species and occur at different developmental stages and even in different states of consciousness. This evidence, based on the automatic electrophysiological change-detection response mismatch negativity (MMN), its magnetoencephalographic equivalent MMNm, and behavioral data, indicates that in audition surprisingly complex processes occur automatically and mainly in the…

Assessing attention allocation toward threat-related stimuli: a comparison of the emotional Stroop task and the attentional probe task

2003

This study examined the association of two widely used measures of attention allocation toward or away from threat-related stimuli: The emotional Stroop task and the attentional probe task. Fifty-three participants responded to computer versions of both tasks where stimuli were presented both subliminally and supraliminally. Thus, four indexes indicating attention allocation were computed for each participant. A correlation analysis showed that the attentional probe index and the emotional Stroop index were associated within each presentation mode while all other relations were nonsignificant. These results are discussed in terms of a distinction between preattentive and attentional process…

Emotional Seesaw, Compliance, and Mindlessness

2001

Research on emotion conducted so far has ignored situations where the subject experiences a certain emotion, but where the external stimulus that evoked and upholds this emotion suddenly disappears. This kind of situation, however, is relatively common in everyday life. This article attempts to recognize certain consequences of those conditions under which the stimuli justifying our experience of such emotional states as fear or joy suddenly disappear. Research done to date by the author and colleagues indicates increased compliance of the subject when addressed with various requests, commands, or suggestions in the situation termed here “emotional seesaw.” The classical “live” example tha…

Behavioural thresholds of blue tit colour vision and the effect of background chromatic complexity

2020

Vision is a vital attribute to foraging, navigation, mate selection and social signalling in animals, which often have a very different colour perception in comparison to humans. For understanding how animal colour perception works, vision models provide the smallest colour difference that animals of a given species are assumed to detect. To determine the just-noticeable-difference, or JND, vision models use Weber fractions that set discrimination thresholds of a stimulus compared to its background. However, although vision models are widely used, they rely on assumptions of Weber fractions since the exact fractions are unknown for most species. Here, we test; i) which Weber fractions in lo…

Further evidence that the effects of repetition on subjective time depend on repetition probability

2017

Repeated stimuli typically have shorter apparent duration than novel stimuli. Most explanations for this effect have attributed it to the repeated stimuli being more expected or predictable than the novel items, but an emerging body of work suggests that repetition and expectation exert distinct effects on time perception. The present experiment replicated a recent study in which the probability of repetition was varied between blocks of trials. As in the previous work, the repetition effect was smaller when repeats were common (and therefore more expected) than when they were rare. These results add to growing evidence that, contrary to traditional accounts, expectation increases apparent …