Social and Behavioral Sciences Commons^™

Circuits Underlying Serotonin Mediated Sex Differences In Fear Learning, Rebecca Ravenelle

Dissertations, Theses, and Capstone Projects

Post-traumatic stress disorder (PTSD) is a trauma-related disorder characterized by intense fearful memory formation. Women are twice as likely as men to develop PTSD, indicating there may be sex differences in the underlying neural circuits. Given that serotonin (5-HT) dysfunction is implicated in PTSD, and 5-HT modulates fear learning, we investigated whether there are sex differences in the modulation of fear learning by 5-HT. We administered the selective serotonin reuptake inhibitor (SSRI) citalopram (20mg/kg or 10m/kg, i.p.) once to male and female mice prior to auditory fear conditioning and tested the effects on fear memory the next day. We found …

Trustworthiness Appraisal Deficits In Borderline Personality Disorder Are Associated With Prefrontal Cortex, Not Amygdala, Impairment, Eric A. Fertuck, Jack Grinband, J. John Mann, Joy Hirsch, Kevin Ochsner, Paul Pilkonis, Jeff Erbe, Barbara Stanley

Publications and Research

Background

Borderline Personality Disorder (BPD) is associated with sensitivity to signals of interpersonal threats and misplaced trust in others. The amygdala, an integral part of the threat evaluation and response network, responds to both fear- and trust-related stimuli in non-clinical samples, and is more sensitive to emotional stimuli in BPD compared to controls. However, it is unknown whether the amygdalar response can account for deficits of trust and elevated sensitivity to interpersonal threat in BPD.

Methods

Facial stimuli were presented to 16 medication-free women with BPD and 17 demographically-matched healthy controls (total n = 33). Participants appraised fearfulness or trustworthiness …

Smaller Hippocampal Volume In Posttraumatic Stress Disorder: A Multisite Enigma-Pgc Study: Subcortical Volumetry Results From Posttraumatic Stress Disorder Consortia, Mark W. Logue, Sanne Jh Van Rooij, Emily L. Dennis, Sarah L. Davis, Lauren O’Connor

Publications and Research

BACKGROUND—Many studies report smaller hippocampal and amygdala volumes in posttraumatic stress disorder (PTSD), but findings have not always been consistent. Here, we present the results of a large-scale neuroimaging consortium study on PTSD conducted by the Psychiatric Genomics Consortium (PGC)–Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) PTSD Working Group.

METHODS—We analyzed neuroimaging and clinical data from 1868 subjects (794 PTSD patients) contributed by 16 cohorts, representing the largest neuroimaging study of PTSD to date. We assessed the volumes of eight subcortical structures (nucleus accumbens, amygdala, caudate, hippocampus, pallidum, putamen, thalamus, and lateral ventricle). We used a standardized image-analysis and …

Neural Hypervigilance In Trauma-Exposed Women, Seungyeon A. Yoon

Dissertations, Theses, and Capstone Projects

Trauma-exposed people often experience hypervigilance, which is a tonic condition of elevated alertness and excessive scanning for potential threat. A cardinal feature of hypervigilance is that no actual threat is needed to evoke or maintain the over-alertness and heightened affective response. However, most neuroimaging research in trauma to date has only focused on reactivity to an actual threat. Thus, the overarching aim of this dissertation was to investigate neural signatures and salivary markers of post-trauma hypervigilance in the absence of threat that can cause impairment in daily functioning and contribute to developing other trauma-related symptoms such as heightened threat reactivity. …

Persistent Amygdala Novelty Response Is Associated With Less Anterior Cingulum Integrity In Trauma-Exposed Women, Seungyeon A. Yoon, Mariann R. Weierich

Publications and Research

Objectives: We investigated the potential role of cingulum and uncinate fasciculus integrity in trauma-related neural hypervigilance, indexed by less discrimination between amygdala activation to novel and familiar affective images.

Participants: 22 women (mean age 21.7 ± 3.9 years) with a history of trauma, and 20 no-trauma controls (mean age 21.9 ± 4.8 years).

Measures: Trauma exposure and trauma-related symptoms were assessed during structured clinical interview. White matter integrity in the anterior cingulum, parahippocampal cingulum, and uncinate fasciculus was measured using diffusion weighted imaging. Amygdala response to novel and familiar affective scenes was measured with functional magnetic resonance imaging.

Results: Trauma-exposed …

It’S Time To Fear! Interval Timing In Odor Fear Conditioning In Rats, Kiseko Shionoya, Chloé Hegoburu, Bruce L. Brown, Regina M. Sullivan, Valérie Doyère, Anne-Marie Mouly

Publications and Research

Time perception is crucial to goal attainment in humans and other animals, and interval timing also guides fundamental animal behaviors. Accumulating evidence has made it clear that in associative learning, temporal relations between events are encoded, and a few studies suggest this temporal learning occurs very rapidly. Most of these studies, however, have used methodologies that do not permit investigating the emergence of this temporal learning. In the present study we monitored respiration, ultrasonic vocalization (USV) and freezing behavior in rats in order to perform fine-grain analysis of fear responses during odor fear conditioning. In this paradigm an initially neutral …