The Experts below are selected from a list of 80442 Experts worldwide ranked by ideXlab platform
Haibin Sun - One of the best experts on this subject based on the ideXlab platform.
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Efficient algorithms for Spatial Configuration information retrieval
Knowledge-Based Systems, 2009Co-Authors: Haibin SunAbstract:The problem of Spatial Configuration information retrieval is a constraint satisfaction problem (CSP), which can be solved using traditional CSP algorithms. But the Spatial data can be reorganized using index techniques like R-tree and the Spatial data are approximated by their minimum bounding rectangles (MBRs), so the Spatial Configuration information retrieval is actually based on the MBRs and some special techniques can be studied. This paper studies the mapping relationships among the Spatial relations for real Spatial objects, the corresponding Spatial relations for their MBRs and the corresponding Spatial relations between the intermediate nodes and the MBRs in R-tree. Three algorithms are designed and studied, and their performances are compared.
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SNPD (1) - Research on Technologies of Spatial Configuration Information Retrieval
Eighth ACIS International Conference on Software Engineering Artificial Intelligence Networking and Parallel Distributed Computing (SNPD 2007), 2007Co-Authors: Haibin Sun, Xin ChenAbstract:The problem of Spatial Configuration information retrieval is a constraint satisfaction problem (CSP), which can be solved using traditional CSP algorithms. But the Spatial data are generally reorganized using index techniques like R-tree to improve the efficiency of query answering in Spatial information systems, especially geographic information system (GIS), and the Spatial data are approximated by their minimum bounding rectangles (MBRs), so the Spatial Configuration information retrieval is actually based on the MBRs and some special techniques should be studied. This paper studies the mapping relationships among the Spatial relations for real Spatial objects, the corresponding Spatial relations for their MBRs and the corresponding Spatial relations between the intermediate nodes and the MBRs in R-tree. Based on these study results, three search algorithms are designed and presented.
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International Conference on Computational Science (2) - Research on Technologies of Spatial Configuration Information Retrieval
Computational Science – ICCS 2007, 2007Co-Authors: Haibin SunAbstract:The problem of Spatial Configuration information retrieval is a Constraint Satisfaction Problem (CSP), which can be solved using traditional CSP algorithms. But the Spatial data can be reorganized using index techniques like R-tree and the Spatial data are approximated by their Minimum Bounding Rectangles (MBRs), so the Spatial Configuration information retrieval is actually based on the MBRs and some special techniques can be studied. This paper studies the mapping relationships among the Spatial relations for real Spatial objects, the corresponding Spatial relations for their MBRs and the corresponding Spatial relations between the intermediate nodes and the MBRs in R-tree.
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BIS - Efficient algorithms for Spatial Configuration information retrieval
Business Information Systems, 1Co-Authors: Haibin Sun, Xin ChenAbstract:The problem of Spatial Configuration information retrieval is a Constraint Satisfaction Problem (CSP), which can be solved using traditional CSP algorithms. But the Spatial data can be reorganized using index techniques like R-tree and the Spatial data are approximated by their Minimum Bounding Rectangles (MBRs), so the Spatial Configuration information retrieval is actually based on the MBRs and some special techniques can be studied. This paper studies the mapping relationships among the Spatial relations for real Spatial objects, the corresponding Spatial relations for their MBRs and the corresponding Spatial relations between the intermediate nodes and the MBRs in R-tree. Three algorithms are designed and studied, and their performances are compared.
Tom Smeets - One of the best experts on this subject based on the ideXlab platform.
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Acute stress - but not aversive scene content - impairs Spatial Configuration learning
Cognition & emotion, 2019Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, James A. Bisby, Tom SmeetsAbstract:Contextual learning pervades our perception and cognition and plays a critical role in adjusting to aversive and stressful events. Our ability to memorise Spatial context has been studied extensively with the contextual cueing paradigm, in which participants search for targets among simple distractor cues and show search advantages for distractor Configurations that repeat across trials. Mixed evidence suggests that confrontation with adversity can enhance as well as impair the contextual cueing effect. We aimed to investigate this relationship more systematically by devising a contextual cueing task that tests Spatial Configuration learning within complex visual scenes that were emotionally neutral or negative (Study 1) and was preceded by the Maastricht Acute Stress Test (MAST) or a no-stress control condition (Study 2). We demonstrate a robust contextual cueing effect that was comparable across negative and neutral scenes (Study 1). In Study 2, acute stress disrupted Spatial Configuration learning irrespective of scene valence and endogenous cortisol reactivity to stress. Together with the emerging evidence in the literature, our findings suggest that Spatial Configuration learning may be subject to complex regulation as a function of Spatial or temporal proximity to a stressor, with potential implications for the development of stress-related psychopathology.
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acute stress differentially affects Spatial Configuration learning in high and low cortisol responding healthy adults
European Journal of Psychotraumatology, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Harald MerckelbachAbstract:Background: Stress and stress hormones modulate memory formation in various ways that are relevant to our understanding of stress-related psychopathology, such as posttraumatic stress disorder (PTSD). Particular relevance is attributed to efficient memory formation sustained by the hippocampus and parahippocampus. This process is thought to reduce the occurrence of intrusions and flashbacks following trauma, but may be negatively affected by acute stress. Moreover, recent evidence suggests that the efficiency of visuo-Spatial processing and learning based on the hippocampal area is related to PTSD symptoms. Objective: The current study investigated the effect of acute stress on Spatial Configuration learning using a Spatial contextual cueing task (SCCT) known to heavily rely on structures in the parahippocampus. Method: Acute stress was induced by subjecting participants (N=34) to the Maastricht Acute Stress Test (MAST). Following a counterbalanced within-subject approach, the effects of stress and the ensuing hormonal (i.e., cortisol) activity on subsequent SCCT performance were compared to SCCT performance following a no-stress control condition. Results: Acute stress did not impact SCCT learning overall, but opposing effects emerged for high versus low cortisol responders to the MAST. Learning scores following stress were reduced in low cortisol responders, while high cortisol-responding participants showed improved learning. Conclusions: The effects of stress on Spatial Configuration learning were moderated by the magnitude of endogenous cortisol secretion. These findings suggest a possible mechanism by which cortisol responses serve an adaptive function during stress and trauma, and this may prove to be a promising route for future research in this area. Keywords: Maastricht Acute Stress Test; contextual cueing paradigm; Spatial memory; hippocampal area; posttraumatic stress disorder (Published: 2 May 2013) For the abstract or full text in other languages, please see Supplementary files in the column to the right (under Article Tools) Citation: European Journal of Psychotraumatology 2013, 4 : 19854 - http://dx.doi.org/10.3402/ejpt.v4i0.19854 This paper is part of the thematic cluster Psychotrauma research in the Netherlands - more papers from this cluster can be found here .
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive Affective & Behavioral Neuroscience, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010 ) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants ( N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = −.33, p < .01, but was unrelated to physiological responses to trauma reminder images ( p s > .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, r s > −.12, p s > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = −.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive affective & behavioral neuroscience, 2012Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = -.33, p .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > -.12, ps > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = -.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
Thomas Meyer - One of the best experts on this subject based on the ideXlab platform.
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Acute stress - but not aversive scene content - impairs Spatial Configuration learning
Cognition & emotion, 2019Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, James A. Bisby, Tom SmeetsAbstract:Contextual learning pervades our perception and cognition and plays a critical role in adjusting to aversive and stressful events. Our ability to memorise Spatial context has been studied extensively with the contextual cueing paradigm, in which participants search for targets among simple distractor cues and show search advantages for distractor Configurations that repeat across trials. Mixed evidence suggests that confrontation with adversity can enhance as well as impair the contextual cueing effect. We aimed to investigate this relationship more systematically by devising a contextual cueing task that tests Spatial Configuration learning within complex visual scenes that were emotionally neutral or negative (Study 1) and was preceded by the Maastricht Acute Stress Test (MAST) or a no-stress control condition (Study 2). We demonstrate a robust contextual cueing effect that was comparable across negative and neutral scenes (Study 1). In Study 2, acute stress disrupted Spatial Configuration learning irrespective of scene valence and endogenous cortisol reactivity to stress. Together with the emerging evidence in the literature, our findings suggest that Spatial Configuration learning may be subject to complex regulation as a function of Spatial or temporal proximity to a stressor, with potential implications for the development of stress-related psychopathology.
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acute stress differentially affects Spatial Configuration learning in high and low cortisol responding healthy adults
European Journal of Psychotraumatology, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Harald MerckelbachAbstract:Background: Stress and stress hormones modulate memory formation in various ways that are relevant to our understanding of stress-related psychopathology, such as posttraumatic stress disorder (PTSD). Particular relevance is attributed to efficient memory formation sustained by the hippocampus and parahippocampus. This process is thought to reduce the occurrence of intrusions and flashbacks following trauma, but may be negatively affected by acute stress. Moreover, recent evidence suggests that the efficiency of visuo-Spatial processing and learning based on the hippocampal area is related to PTSD symptoms. Objective: The current study investigated the effect of acute stress on Spatial Configuration learning using a Spatial contextual cueing task (SCCT) known to heavily rely on structures in the parahippocampus. Method: Acute stress was induced by subjecting participants (N=34) to the Maastricht Acute Stress Test (MAST). Following a counterbalanced within-subject approach, the effects of stress and the ensuing hormonal (i.e., cortisol) activity on subsequent SCCT performance were compared to SCCT performance following a no-stress control condition. Results: Acute stress did not impact SCCT learning overall, but opposing effects emerged for high versus low cortisol responders to the MAST. Learning scores following stress were reduced in low cortisol responders, while high cortisol-responding participants showed improved learning. Conclusions: The effects of stress on Spatial Configuration learning were moderated by the magnitude of endogenous cortisol secretion. These findings suggest a possible mechanism by which cortisol responses serve an adaptive function during stress and trauma, and this may prove to be a promising route for future research in this area. Keywords: Maastricht Acute Stress Test; contextual cueing paradigm; Spatial memory; hippocampal area; posttraumatic stress disorder (Published: 2 May 2013) For the abstract or full text in other languages, please see Supplementary files in the column to the right (under Article Tools) Citation: European Journal of Psychotraumatology 2013, 4 : 19854 - http://dx.doi.org/10.3402/ejpt.v4i0.19854 This paper is part of the thematic cluster Psychotrauma research in the Netherlands - more papers from this cluster can be found here .
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive Affective & Behavioral Neuroscience, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010 ) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants ( N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = −.33, p < .01, but was unrelated to physiological responses to trauma reminder images ( p s > .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, r s > −.12, p s > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = −.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive affective & behavioral neuroscience, 2012Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = -.33, p .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > -.12, ps > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = -.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
Harald Merckelbach - One of the best experts on this subject based on the ideXlab platform.
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acute stress differentially affects Spatial Configuration learning in high and low cortisol responding healthy adults
European Journal of Psychotraumatology, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Harald MerckelbachAbstract:Background: Stress and stress hormones modulate memory formation in various ways that are relevant to our understanding of stress-related psychopathology, such as posttraumatic stress disorder (PTSD). Particular relevance is attributed to efficient memory formation sustained by the hippocampus and parahippocampus. This process is thought to reduce the occurrence of intrusions and flashbacks following trauma, but may be negatively affected by acute stress. Moreover, recent evidence suggests that the efficiency of visuo-Spatial processing and learning based on the hippocampal area is related to PTSD symptoms. Objective: The current study investigated the effect of acute stress on Spatial Configuration learning using a Spatial contextual cueing task (SCCT) known to heavily rely on structures in the parahippocampus. Method: Acute stress was induced by subjecting participants (N=34) to the Maastricht Acute Stress Test (MAST). Following a counterbalanced within-subject approach, the effects of stress and the ensuing hormonal (i.e., cortisol) activity on subsequent SCCT performance were compared to SCCT performance following a no-stress control condition. Results: Acute stress did not impact SCCT learning overall, but opposing effects emerged for high versus low cortisol responders to the MAST. Learning scores following stress were reduced in low cortisol responders, while high cortisol-responding participants showed improved learning. Conclusions: The effects of stress on Spatial Configuration learning were moderated by the magnitude of endogenous cortisol secretion. These findings suggest a possible mechanism by which cortisol responses serve an adaptive function during stress and trauma, and this may prove to be a promising route for future research in this area. Keywords: Maastricht Acute Stress Test; contextual cueing paradigm; Spatial memory; hippocampal area; posttraumatic stress disorder (Published: 2 May 2013) For the abstract or full text in other languages, please see Supplementary files in the column to the right (under Article Tools) Citation: European Journal of Psychotraumatology 2013, 4 : 19854 - http://dx.doi.org/10.3402/ejpt.v4i0.19854 This paper is part of the thematic cluster Psychotrauma research in the Netherlands - more papers from this cluster can be found here .
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive Affective & Behavioral Neuroscience, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010 ) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants ( N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = −.33, p < .01, but was unrelated to physiological responses to trauma reminder images ( p s > .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, r s > −.12, p s > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = −.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive affective & behavioral neuroscience, 2012Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = -.33, p .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > -.12, ps > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = -.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
Conny W.e.m. Quaedflieg - One of the best experts on this subject based on the ideXlab platform.
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Acute stress - but not aversive scene content - impairs Spatial Configuration learning
Cognition & emotion, 2019Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, James A. Bisby, Tom SmeetsAbstract:Contextual learning pervades our perception and cognition and plays a critical role in adjusting to aversive and stressful events. Our ability to memorise Spatial context has been studied extensively with the contextual cueing paradigm, in which participants search for targets among simple distractor cues and show search advantages for distractor Configurations that repeat across trials. Mixed evidence suggests that confrontation with adversity can enhance as well as impair the contextual cueing effect. We aimed to investigate this relationship more systematically by devising a contextual cueing task that tests Spatial Configuration learning within complex visual scenes that were emotionally neutral or negative (Study 1) and was preceded by the Maastricht Acute Stress Test (MAST) or a no-stress control condition (Study 2). We demonstrate a robust contextual cueing effect that was comparable across negative and neutral scenes (Study 1). In Study 2, acute stress disrupted Spatial Configuration learning irrespective of scene valence and endogenous cortisol reactivity to stress. Together with the emerging evidence in the literature, our findings suggest that Spatial Configuration learning may be subject to complex regulation as a function of Spatial or temporal proximity to a stressor, with potential implications for the development of stress-related psychopathology.
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acute stress differentially affects Spatial Configuration learning in high and low cortisol responding healthy adults
European Journal of Psychotraumatology, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Harald MerckelbachAbstract:Background: Stress and stress hormones modulate memory formation in various ways that are relevant to our understanding of stress-related psychopathology, such as posttraumatic stress disorder (PTSD). Particular relevance is attributed to efficient memory formation sustained by the hippocampus and parahippocampus. This process is thought to reduce the occurrence of intrusions and flashbacks following trauma, but may be negatively affected by acute stress. Moreover, recent evidence suggests that the efficiency of visuo-Spatial processing and learning based on the hippocampal area is related to PTSD symptoms. Objective: The current study investigated the effect of acute stress on Spatial Configuration learning using a Spatial contextual cueing task (SCCT) known to heavily rely on structures in the parahippocampus. Method: Acute stress was induced by subjecting participants (N=34) to the Maastricht Acute Stress Test (MAST). Following a counterbalanced within-subject approach, the effects of stress and the ensuing hormonal (i.e., cortisol) activity on subsequent SCCT performance were compared to SCCT performance following a no-stress control condition. Results: Acute stress did not impact SCCT learning overall, but opposing effects emerged for high versus low cortisol responders to the MAST. Learning scores following stress were reduced in low cortisol responders, while high cortisol-responding participants showed improved learning. Conclusions: The effects of stress on Spatial Configuration learning were moderated by the magnitude of endogenous cortisol secretion. These findings suggest a possible mechanism by which cortisol responses serve an adaptive function during stress and trauma, and this may prove to be a promising route for future research in this area. Keywords: Maastricht Acute Stress Test; contextual cueing paradigm; Spatial memory; hippocampal area; posttraumatic stress disorder (Published: 2 May 2013) For the abstract or full text in other languages, please see Supplementary files in the column to the right (under Article Tools) Citation: European Journal of Psychotraumatology 2013, 4 : 19854 - http://dx.doi.org/10.3402/ejpt.v4i0.19854 This paper is part of the thematic cluster Psychotrauma research in the Netherlands - more papers from this cluster can be found here .
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive Affective & Behavioral Neuroscience, 2013Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010 ) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants ( N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = −.33, p < .01, but was unrelated to physiological responses to trauma reminder images ( p s > .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, r s > −.12, p s > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = −.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
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Individual differences in Spatial Configuration learning predict the occurrence of intrusive memories
Cognitive affective & behavioral neuroscience, 2012Co-Authors: Thomas Meyer, Conny W.e.m. Quaedflieg, Tom Smeets, Timo Giesbrecht, Marta M. Girardelli, Georgina R. N. Mackay, Harald MerckelbachAbstract:The dual-representation model of posttraumatic stress disorder (PTSD; Brewin, Gregory, Lipton, & Burgess, Psychological Review, 117, 210-232 2010) argues that intrusions occur when people fail to construct context-based representations during adverse experiences. The present study tested a specific prediction flowing from this model. In particular, we investigated whether the efficiency of temporal-lobe-based Spatial Configuration learning would account for individual differences in intrusive experiences and physiological reactivity in the laboratory. Participants (N = 82) completed the contextual cuing paradigm, which assesses Spatial Configuration learning that is believed to depend on associative encoding in the parahippocampus. They were then shown a trauma film. Afterward, startle responses were quantified during presentation of trauma reminder pictures versus unrelated neutral and emotional pictures. PTSD symptoms were recorded in the week following participation. Better Configuration learning performance was associated with fewer perceptual intrusions, r = -.33, p .46) and had no direct effect on intrusion-related distress and overall PTSD symptoms, rs > -.12, ps > .29. However, Configuration learning performance tended to be associated with reduced physiological responses to unrelated negative images, r = -.20, p = .07. Thus, while Spatial Configuration learning appears to be unrelated to affective responding to trauma reminders, our overall findings support the idea that the context-based memory system helps to reduce intrusions.
