Poster Session F, Tuesday, March 26, 8:00 – 10:00 am, Pacific Concourse
Emotional lability in focal hippocampal damage
Christopher Butler1, Georgios P. D. Argyropoulos1, Lauren Moore1,2, Clare Loane1,3, Adriana Roca-Fernandez1, Carmen Lage-Martinez1,4; 1University of Oxford, 2University of Bath, 3University College London, 4University Hospital Marqués de Valdecilla
A sizeable literature on animal models suggests that the primate anterior hippocampus (homologous to the rodent ventral hippocampus) is embedded within networks regulating emotion and affect. However, very little is known on emotional dysregulation in patients with hippocampal damage. We thus aimed to assess the negative emotional sequelae in focal hippocampal atrophy following autoimmune limbic encephalitis, a neurological disease typically associated with hippocampal damage and residual cognitive and emotional impairment. We focused on emotional lability, i.e. the fluctuating and inappropriate levels of emotional arousal, manifested with labile crying or laughter. We analyzed acute neuroradiological reports, clinical notes, post-acute neuropsychological scores, along with structural MRI and resting-state fMRI datasets in relation to emotional lability in a large cohort of patients (n = 36) that had been treated for limbic encephalitis. Emotional lability was present in 50% of the patients, yet selectively in the form of tearfulness. It was not associated with depression, impulsiveness, memory impairment, or executive dysfunction. While patients showed focal hippocampal atrophy within the medial temporal lobe, hippocampal volumes did not reliably predict tearfulness. Instead, it was the abnormalities in the resting-state hemodynamic activity in and hippocampal functional connectivity with regions in the inferior and superior parietal lobules that were associated with tearfulness. Residual tearfulness is highly common, and it is not a manifestation of depression, pseudobulbar affect, impulsiveness, or executive dysfunction. Functional abnormalities in parietal regions supporting perspective taking and social-affective processing may compromise patients’ emotion regulation following focal hippocampal damage.
Topic Area: EMOTION & SOCIAL: Self perception