The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform

Paul Eelen - One of the best experts on this subject based on the ideXlab platform.

  • non differential return of fear in humans after a reinstatement procedure
    Acta Psychologica, 2009
    Co-Authors: Trinette Dirikx, Debora Vansteenwegen, Paul Eelen, Dirk Hermans
    Abstract:

    The present experiment investigated reinstatement of fear in humans using a differential fear conditioning preparation. In this experiment, one Neutral Stimulus (conditioned Stimulus; CS+) was paired with an aversive Stimulus (unconditioned Stimulus; US) during the acquisition phase, while another Neutral Stimulus was not (CS-). This procedure led to a difference in responding between the CS+ and the CS- (i.e., differential conditioning). After this acquisition phase, an extinction phase followed, during which both CSs were presented without the US, resulting in a decrease in differential conditioned responding. Reinstatement refers to the return of extinguished conditioned responses due to the experience of US-only trials after the extinction phase. This phenomenon was investigated by presenting half of the participants (reinstatement group) with unpredictable USs after the extinction phase. The control group did not receive these USs after the extinction procedure. The results show that return of fear was clearly apparent after the reinstating USs. This return of fear was, however, not limited to the CS+. An increase in 'conditioned' responding was also observed for the control Stimulus. This interesting observation will be discussed against the background of a number of recent theoretical conceptualizations of reinstatement.

  • Beyond evaluative conditioning? Searching for associative transfer of nonevaluative Stimulus properties.
    Cognition & emotion, 2005
    Co-Authors: Tom Meersmans, Jan De Houwer, Frank Baeyens, Tom Randell, Paul Eelen
    Abstract:

    Evaluative conditioning refers to the changes in liking of an evaluatively Neutral Stimulus (the conditional Stimulus or CS) as a result of merely pairing it with another, already liked or disliked Stimulus (the unconditional Stimulus or US). We examined whether other, non-evaluative Stimulus properties of a US can also be associatively transferred to a CS. In a series of experiments, we tried to transfer perceptions of the gender of children and the gender of first names. We found evidence for the associative transfer of these properties but only when participants were aware of the contingencies.

  • observational evaluative conditioning of an embedded Stimulus element
    European Journal of Social Psychology, 1996
    Co-Authors: Frank Baeyens, Paul Eelen, Bart Kaes, Peter Silverans
    Abstract:

    Evaluative conditioning refers to the observation that the mere paired presentation of a Neutral Stimulus (CS) with a liked or disliked Stimulus (US) may result in the Neutral Stimulus itself acquiring positive or negative valence. In most studies, the CS is an autonomous, invariant Stimulus, and the subject directly experiences both CS and US. In this experiment, we investigated whether evaluative conditioning can be extended to a situation wherein the CS is no more than an invariant element of a complex, variable Stimulus configuration, and wherein the subject experiences the CS-US co-occurrences indirectly, i.e. by observing a socius who is exposed to the CS-US pairings and facially expresses either liking or disliking the US. During acquisition, subjects watched video-taped sequences of an actor drinking a glass containing a liquid and facially expressing either liking or disliking the drink. The Stimulus element which was systematically paired with the actor's facial expression of liking or disliking, was whether the glass contained a 'foot' or no 'foot' (CS), while other characteristics of the scenes were systematically varied and paired equally often with an expression of like and dislike. Next, valence ratings were obtained for pictures in which the CS element (foot/no foot) was embedded. A clear observational evaluative learning effect could be demonstrated when the feature CS was embedded in objects identical to those presented during learning, but not when it was embedded in new objects. These data demonstrate the possibility of vicarious evaluative conditioning of an embedded Stimulus element, but probably at a lower level of abstract ion than intended.

P. Martín - One of the best experts on this subject based on the ideXlab platform.

  • Is a Neutral expression also a Neutral Stimulus? A study with functional magnetic resonance.
    Experimental brain research, 2013
    Co-Authors: Fernando Carvajal, Sandra Rubio, Juan M. Serrano, Marcos Ríos-lago, Juan Álvarez-linera, Lara Pacheco, P. Martín
    Abstract:

    Although Neutral faces do not initially convey an explicit emotional message, it has been found that individuals tend to assign them an affective content. Moreover, previous research has shown that affective judgments are mediated by the task they have to perform. Using functional magnetic resonance imaging in 21 healthy participants, we focus this study on the cerebral activity patterns triggered by Neutral and emotional faces in two different tasks (social or gender judgments). Results obtained, using conjunction analyses, indicated that viewing both emotional and Neutral faces evokes activity in several similar brain areas indicating a common neural substrate. Moreover, Neutral faces specifically elicit activation of cerebellum, frontal and temporal areas, while emotional faces involve the cuneus, anterior cingulated gyrus, medial orbitofrontal cortex, posterior superior temporal gyrus, precentral/postcentral gyrus and insula. The task selected was also found to influence brain activity, in that the social task recruited frontal areas while the gender task involved the posterior cingulated, inferior parietal lobule and middle temporal gyrus to a greater extent. Specifically, in the social task viewing Neutral faces was associated with longer reaction times and increased activity of left dorsolateral frontal cortex compared with viewing facial expressions of emotions. In contrast, in the same task emotional expressions distinctively activated the left amygdale. The results are discussed taking into consideration the fact that, like other facial expressions, Neutral expressions are usually assigned some emotional significance. However, Neutral faces evoke a greater activation of circuits probably involved in more elaborate cognitive processing.

Joy Hirsch - One of the best experts on this subject based on the ideXlab platform.

  • A translational bridge between mouse and human models of learned safety
    Annals of medicine, 2010
    Co-Authors: Daniela D. Pollak, Michael T. Rogan, Tobias Egner, David L. Perez, Ted K. Yanagihara, Joy Hirsch
    Abstract:

    Background. Learned safety is established by negatively correlating the occurrence of a Neutral Stimulus and a noxious Stimulus, which renders the previously Neutral Stimulus a ‘safety signal’. While the neurophysiological and molecular mechanisms have been characterized in mice, it is currently not known how the neural substrates involved compare between mice and people. Methods. Here we attempt to adapt the original animal protocol to humans and use functional magnetic resonance imaging to examine neural responses to the conditioned Stimulus in safety conditioned and fear conditioned subjects. Diffusion tensor imaging (DTI) was used in a parallel group of subjects as a fi rst approach to delineate the underlying neural circuitry. Results. Learned safety is associated with dampened amygdala and increased dorsolateral prefrontal cortex and caudate responses and paralleled by pupillary constriction. A neural connection between the amygdala and the dorsolateral prefrontal cortex is suggested by DTI. Conclusion. We present a translational bridge between mouse and human models of learned safety in which cellular and molecular insights from animal experiments are extended to the human neural circuitry. This study provides an example of how animal experiments can be used to inform and target human studies, which in turn can corroborate results obtained in experimental animals.

Robert E Kleck - One of the best experts on this subject based on the ideXlab platform.

  • effects of talking about a stressful event on arousal does what we talk about make a difference
    Journal of Personality and Social Psychology, 1993
    Co-Authors: Marilyn Mendolia, Robert E Kleck
    Abstract:

    In Study 1, 30 male and 30 female undergraduates viewed an affect-Neutral Stimulus and a stress-inducing Stimulus. Ss then talked about either their emotional reactions to the stressful Stimulus (emotion condition), the sequence of events within it (fact condition), or the sequence of events within the Neutral Stimulus (distraction condition). Emotion-condition Ss were more autonomically aroused during a 2nd exposure to the stressful Stimulus than were fact-condition Ss. In Study 2, 48 hr separated Ss' talking about their 1st exposure to the stressful Stimulus from their 2nd exposure to it. Emotion-condition Ss had lower levels of autonomic arousal while viewing the Stimulus again and reported more positive affect after watching it than did fact-condition Ss. These results are discussed in the context of cognitive appraisal, perceptual-motor, and self-disclosure views of emotion.

Tim Klucken - One of the best experts on this subject based on the ideXlab platform.

  • Relationship of sensation seeking with the neural correlates of appetitive conditioning.
    Social cognitive and affective neuroscience, 2019
    Co-Authors: Isabell Tapia León, Onno Kruse, Rudolf Stark, Tim Klucken
    Abstract:

    Previous research has linked sensation seeking with a heightened risk for drug abuse and other risk-taking behavior. As appetitive conditioning presents a model for the etiology and maintenance of addictive behavior, investigating sensation seeking in a classical conditioning paradigm might elucidate possible pathways toward addiction within this model. Furthermore, the theoretical concept underlying sensation seeking proposes a negative relationship between reward processing and sensation seeking in only moderately arousing situations, which has been neglected by previous research. This study aimed to investigate this inverse relationship in moderately stimulating situations entailing reward processing using functional magnetic resonance imaging. Subjects (N = 38) participated in a classical conditioning paradigm in which a Neutral Stimulus (CS+) was repeatedly paired with a monetary reward, while another Neutral Stimulus (CS-) was not. Imaging results revealed a negative relationship between sensation seeking and neural responses in the insula, amygdala and nucleus accumbens during the early phase and in the dorsal anterior cingulate cortex during the late phase of conditioning. These findings suggest reduced reward learning and consequently diminished processing of outcome expectancy in appetitive conditioning in subjects with high sensation seeking scores. The results are discussed with respect to clinical implications.

  • Neural correlates of subjective CS/UCS association in appetitive conditioning.
    Human brain mapping, 2018
    Co-Authors: Isabell Tapia León, Onno Kruse, Rudolf Stark, Tobias Stalder, Tim Klucken
    Abstract:

    Explicit knowledge of conditioned Stimulus (CS)/unconditioned Stimulus (UCS) associations is proposed as important factor in classical conditioning. However, while previous studies have focused on its roles in fear conditioning, it has been neglected in the context of appetitive conditioning. The present functional magnetic resonance study aimed to investigate neural activation and functional connectivity linked to subjective CS/UCS association in appetitive conditioning. In total, 85 subjects participated in an appetitive acquisition procedure in which a Neutral Stimulus (CS+) was paired with a monetary reward, while another Neutral Stimulus (CS-) was never paired with the reward. Directly afterwards, subjective CS/UCS association was assessed by measuring the extent to which the CS+ was thought to be associated with the UCS compared to the CS-. Close relationships were established between subjective CS/UCS association and activations in the primary visual cortex (V1) during the early phase of conditioning and in the striatum during the late conditioning phase. In addition, we observed inverse relationships between subjective CS/UCS association and both V1/ventromedial prefrontal cortex (vmPFC) and striatal/vmPFC connectivity. The results suggest the involvement of decoupling vmPFC connectivity in reward learning in general and the roles of attentional processes in the formation of the subjective CS/UCS association during the early phase and reward prediction during the late phase of appetitive conditioning.