Reduced hippocampal volume is associated with overgeneralization of negative context in individuals with PTSD.

Levy-Gigi, Einat; Szabó, Csilla; Richter‐Levin, Gal; Kéri, Szabolcs

doi:10.1037/neu0000131

Cited by 76 publications

(76 citation statements)

References 86 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increased generalization has now been observed in three different studies of PTSD: in the first study, participants recruited from the same Veteran population as the current study were assessed on an acquired equivalence task (Kostek et al, 2014), and in the second, trauma-exposed individuals from a very different population (individuals with clinically-diagnosed PTSD and a single exposure to trauma) were assessed on a contextual processing task (Levy-Gigi et al, 2015). The current study assessed a different type of generalization: the ability to transfer learning when relevant stimulus features remain stable and irrelevant stimulus features are altered.…”

Section: Discussionmentioning

confidence: 86%

“…One interpretation is that the hippocampus and associated medial temporal lobe structures are important for the flexibility with which learning can be applied to changing task conditions (Eichenbaum, Otto, & Cohen, 1992; Squire & Knowlton, 1995). Given that hippocampal volume often has been found to be reduced in PTSD (Gilbertson et al, 2002; Levy-Gigi et al, 2015; Smith, 2005), we might have expected that patients with PTSD would show impaired generalization. However, the medial temporal lobe includes several structures, each with distinct anatomy and physiology, and presumably with distinct function.…”

Section: Discussionmentioning

confidence: 99%

“…Thus, for example, when given specific cue words and asked to retrieve specific autobiographical memories, those with PTSD typically recall fewer specific episodes and the retrieved memories have fewer details (e.g., Brown, Williams, Bray, & Hourani, 2012; McNally, Lasko, Macklin, & Pitman, 1995). Increased generalization is also observed in associative learning tasks involving purely cognitive, impersonal information (Kostek et al, 2014; Levy-Gigi, Szabo, Richter-Levin, & Kéri, 2015). For example, a contextual processing task with positive and negative outcomes showed increased generalization of negative context in individuals with clinically diagnosed PTSD.…”

Section: Introductionmentioning

confidence: 93%

“…For example, a contextual processing task with positive and negative outcomes showed increased generalization of negative context in individuals with clinically diagnosed PTSD. When a negative outcome (context) was initially paired with a cue, individuals with PTSD had difficulty subsequently learning to associate that same cue with a now positive outcome (Levy-Gigi et al, 2015). …”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Increased generalization of learned associations is related to re-experiencing symptoms in veterans with symptoms of post-traumatic stress

Anastasides¹,

Beck²,

Pang³

et al. 2015

Stress

View full text Add to dashboard Cite

One interpretation of re-experiencing symptoms in post-traumatic stress disorder (PTSD) is that memories related to emotional information are stored strongly, but with insufficient specificity, so that stimuli which are minimally related to the traumatic event are sufficient to trigger recall. If so, re-experiencing symptoms may reflect a general bias against encoding background information during a learning experience, and this tendency might not be limited to learning about traumatic or even autobiographical events. To test this possibility, we administered a discrimination-and-transfer task to 60 Veterans (11.2% female, mean age 54.0 years) self-assessed for PTSD symptoms in order to examine whether re-experiencing symptoms were associated with increased generalization following associative learning. The discrimination task involved learning to choose the rewarded object from each of six object pairs; each pair differed in colour or shape but not both. In the transfer phase, the irrelevant feature in each pair was altered. Regression analysis revealed no relationships between re-experiencing symptoms and initial discrimination learning. However, re-experiencing symptom scores contributed to the prediction of transfer performance. Other PTSD symptom clusters (avoidance/numbing, hyperarousal) did not account for significant additional variance. The results are consistent with an emerging interpretation of re-experiencing symptoms as reflecting a learning bias that favours generalization at the expense of specificity. Future studies will be needed to determine whether this learning bias may pre-date and confer risk for, re-experiencing symptoms in individuals subsequently exposed to trauma, or emerges only in the wake of trauma exposure and PTSD symptom development.

show abstract

Section: Discussionmentioning

confidence: 86%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Increased generalization of learned associations is related to re-experiencing symptoms in veterans with symptoms of post-traumatic stress

Anastasides¹,

Beck²,

Pang³

et al. 2015

Stress

View full text Add to dashboard Cite

show abstract

“…Levy-Gigi, Richter-Levin, Szabo and Keri (2015) show that overgeneralization of nega tive context in people with post-traumatic stress disorder (PTSD) significantly correlated with hippocampal volume and conclude that reduced hippocampal volume may account for the difficulty of people with PTSD to differentiate negative and novel conditions, and thus may facilitate reexperiencing symptoms [10]. But there was strictly unclear, whether the reduced hippocampal volume is a result of PTSD or, maybe, a risk factor.…”

Section: Molecular Basis Of Hippocampus Memory Functionmentioning

confidence: 99%

Role of the hippocampus in memory functioning: modern view

Assonov

Bozhuk

2017

ZMJ

View full text Add to dashboard Cite

The purpose of this review was to develop the comprehensive conception of the hippocampus role in the functioning of human memory, based on data obtained by analysis of the latest scientific literature on the topic and make recommendations for further ways of researches in this topic. The scientific literature of the last 5 years on the role of the hippocampus in memory functioning was analyzed.Based on the reviewed literature, we made the next conclusions: the hippocampus is an extremely important for memory structure with various connections for different types of memory; the hippocampus is affected by a variety of substances, most studied now are glucocorticosteroids, whose effect on memory differs depending on the start time of action; the hippocampus volume in mental disorders affecting memory is less than normal, which makes it an important diagnostic criterion; at the moment, various promising methods that can help in the therapy of PTSD, depression, phobias and other disorders associated with memory impairment and based on the knowledge of the hippocampus for the treatment of memory disorders are being developed. Based on these conclusions and data, which were analyzed, we offered the following recommendations: to implement the hippocampal function examination in the diagnostics of mental disorders, which are accompanied by a violation of its work; to use the size of the hippocampus as one of the prognostic factors for the severity of the memory-associated disorders and the therapy progress; to carefully investigate the difference in the effect of various psychotherapies and pharmacotherapies on the hippocampus to determine exactly which of the therapies is the most morphologically reasonable; to find out how significant the decrease in the hippocampal volume is for the memory functioning; to use pathogenetically and morphologically based methods to improve the function of the hippocampus in the treatment of disorders that are accompanied by memory problems.Роль гіпокампа в роботі пам'яті: сучасний поглядМета роботи -розробити всебічну концепцію ролі гіпокампа у функціонуванні пам'яті людини на основі даних, що отри-мані під час аналізу новітньої наукової літератури з цієї теми, а також виробити рекомендації для дальших досліджень у цій області. Аналізувалась наукова література останніх 5 років про роль гіпокампа у функціонуванні пам'яті.Висновки. Гіпокамп є дуже важливою структурою пам'яті зі зв'язками, які відрізняються для різних типів пам'яті. На гіпокамп впливають різні речовини, найбільш вивченими серед них нині є глюкокортикостероїди, дія яких на пам'ять відрізняється залежно від часу початку їхньої дії. Розмір гіпокампа при психічних розладах, що впливають на пам'ять, менше норми, що робить його важливим діагностичним критерієм. Зараз розробляються різні перспективні методи, що можуть допомогти в терапії посттравматичного стресового розладу, депресії, фобій та інших розладів, котрі пов'язані з погіршенням пам'яті та засновані на знанні гіпокампа для лікування розладів пам'яті. На підставі цих вис...

show abstract

Cannabinoid polymorphisms interact with plasma endocannabinoid levels to predict fear extinction learning

Ney

Matthews

Hsu

et al. 2021

Depression and Anxiety

View full text Add to dashboard Cite

Background The endocannabinoid system is gaining increasing attention as a favorable target for improving posttraumatic stress disorder (PTSD) treatments. Exposure therapy is the gold‐standard treatment for PTSD, and fear extinction learning is a key concept underlying successful exposure. Methods This study examined the role of genetic endocannabinoid polymorphisms in a fear extinction paradigm with PTSD compared to healthy participants (N = 220). Participants provided saliva for genotyping, completed a fear conditioning and extinction task, with blood samples taken before and after the task (n = 57). Skin conductance was the outcome and was analyzed using mixed models. Results Results for cannabinoid receptor type 1 polymorphisms suggested that minor alleles of rs2180619 and rs1049353 were associated with poorer extinction learning in PTSD participants. The minor allele of the fatty acid amide hydrolase (FAAH) polymorphism rs324420 was associated with worse extinction in PTSD participants. Subanalysis of healthy participants (n = 57) showed the FAAH rs324420 genotype effect was dependent on plasma arachidonoyl ethanolamide (AEA) level, but not oleoylethanolamide or 2‐arachidonoyl glycerol. Specifically, higher but not lower AEA levels in conjunction with the minor allele of FAAH rs324420 were associated with better extinction learning. Conclusions These findings provide translational evidence that cannabinoid receptor 1 and AEA are involved in extinction learning in humans. FAAH rs324420's effect on fear extinction is moderated by AEA plasma level in healthy controls. These findings imply that FAAH inhibitors may be effective for targeting anxiety in PTSD, but this effect needs to be explored further in clinical populations.

show abstract

Reduced hippocampal volume is associated with overgeneralization of negative context in individuals with PTSD.

Abstract: Reduced hippocampal volume may account for the difficulty of individuals with PTSD to differentiate negative and novel conditions and hence may facilitate reexperiencing symptoms.

Cited by 76 publications

References 86 publications

Increased generalization of learned associations is related to re-experiencing symptoms in veterans with symptoms of post-traumatic stress

Increased generalization of learned associations is related to re-experiencing symptoms in veterans with symptoms of post-traumatic stress

Role of the hippocampus in memory functioning: modern view

Cannabinoid polymorphisms interact with plasma endocannabinoid levels to predict fear extinction learning

Contact Info

Product

Resources

About