| dc.identifier.uri | http://hdl.handle.net/11401/78197 | |
| dc.description.sponsorship | This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree | en_US |
| dc.format | Monograph | |
| dc.format.medium | Electronic Resource | en_US |
| dc.language.iso | en_US | |
| dc.type | Dissertation | |
| dcterms.abstract | Emotional stimuli require rapid adaptive responses, such as avoidance of threat or approach towards a rewarding stimulus. To allow for fast and accurate detection of threatening stimuli, our perceptual system prioritizes threatening compared to neutral stimuli. Even though there is considerable evidence indicating that perception is guided by top-down factors such as goals and expectations, prioritized detection of threatening stimuli has been hypothesized to occur in a bottom-up manner due to physical characteristics or evolutionary significance. In the present study we examine the psychological and neural mechanisms by which top-down factors influence threat-related perceptual decision making. Participants performed a two-alternative forced-choice perceptual discrimination task in which they were cued to detect perceptually degraded fearful face or neutral face images. These images were presented at the participants’ pre-determined perceptual threshold, while signal detection and fMRI measures were recorded in brain regions that have been shown to be important in the perception of emotional faces. Threat cues led to faster and more accurate perceptual decision making than neutral cues, and to increased neural activity in brain regions important for emotion face perception. In other words, even before arrival of emotional faces, fear cues led to greater brain activation, and this prestimulus activity predicted improvement in subsequent performance. While increases in baseline neural activity provide important information about top-down guidance of perception, an examination of patterns of brain activity can clarify how a threat-related perceptual ‘template’ is represented in the brain. We used multivariate pattern analysis (MVPA) to examine the representation of both cues and stimuli in the brain, as well as the correspondence between the two. Patterns of pre- and post-stimulus activation were more highly correlated for threat cues and threatening faces than for threat cues and neutral faces, or for neutral cues and neutral faces. These results support the predictive-coding hypothesis, suggesting that the brain augments threat-related perceptual decision-making by forming more precise predictive templates of anticipated threatening stimuli. Furthermore, they underscore the importance of including top-down emotion-related processing in models of emotion-perception interactions, and of the future exploration of the impact of top-down processes on perception. | |
| dcterms.available | 2018-03-22T22:39:17Z | |
| dcterms.contributor | Mohanty, Aprajita. | en_US |
| dcterms.contributor | Hajcak, Greg | en_US |
| dcterms.contributor | Egner, Tobias | en_US |
| dcterms.contributor | Luhmann, Christian. | en_US |
| dcterms.creator | Sussman, Tamara Jacobs | |
| dcterms.dateAccepted | 2018-03-22T22:39:17Z | |
| dcterms.dateSubmitted | 2018-03-22T22:39:17Z | |
| dcterms.description | Department of Clinical Psychology. | en_US |
| dcterms.extent | 106 pg. | en_US |
| dcterms.format | Monograph | |
| dcterms.format | Application/PDF | en_US |
| dcterms.identifier | http://hdl.handle.net/11401/78197 | |
| dcterms.issued | 2017-08-01 | |
| dcterms.language | en_US | |
| dcterms.provenance | Made available in DSpace on 2018-03-22T22:39:17Z (GMT). No. of bitstreams: 1
Sussman_grad.sunysb_0771E_13403.pdf: 4380424 bytes, checksum: d8ba6f361fe01c319571474545b99200 (MD5)
Previous issue date: 2017-08-01 | en |
| dcterms.subject | fMRI | |
| dcterms.subject | Cognitive psychology -- Clinical psychology. | |
| dcterms.subject | Multivariate pattern analysis | |
| dcterms.subject | Perceptual decision making | |
| dcterms.subject | Superior temporal sulcus | |
| dcterms.subject | Threat perception | |
| dcterms.subject | Top-down processing | |
| dcterms.title | Threat-related predictive templates in the brain | |
| dcterms.type | Dissertation | |
