title: Impaired acquisition of classically conditioned fear-potentiated startle reflexes in humans with focal bilateral basolateral amygdala damage.
abstract: Based on studies in rodents, the basolateral amygdala (BLA) is considered a key site for experience-dependent neural plasticity underlying the acquisition of conditioned fear responses. In humans, very few studies exist of subjects with selective amygdala lesions and those studies have only implicated the amygdala more broadly leaving the role of amygdala sub-regions underexplored. We tested a rare sample of subjects (N = 4) with unprecedented focal bilateral BLA lesions due to a genetic condition called Urbach-Wiethe disease. In a classical delay fear conditioning experiment, these subjects showed impaired acquisition of conditioned fear relative to a group of matched control subjects (N = 10) as measured by fear-potentiation of the defensive eye-blink startle reflex. After the experiment, the BLA-damaged cases showed normal declarative memory of the conditioned association. Our findings provide new evidence that the human BLA is essential to drive fast classically conditioned defensive reflexes.
authors.affiliation: Department of Experimental Psychology, Utrecht University, 3584 CS Utrecht, The Netherlands, Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behavior, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands, F.Klumpers@donders.ru.nl.
authors.forename: Floris
authors.initials: F
authors.lastname: Klumpers
authors.affiliation: Department of Human Biology, MRC Medical Imaging Research Unit, University of Cape Town, 7700 Cape Town, South Africa.
authors.forename: Barak
authors.initials: B
authors.lastname: Morgan
authors.affiliation: Department of Experimental Psychology, Utrecht University, 3584 CS Utrecht, The Netherlands, Department of Psychiatry and Mental Health, University of Cape Town, 7925 Cape Town, South Africa, and.
authors.forename: David
authors.initials: D
authors.lastname: Terburg
authors.affiliation: Department of Psychiatry and Mental Health, University of Cape Town, 7925 Cape Town, South Africa, and.
authors.forename: Dan J
authors.initials: DJ
authors.lastname: Stein
authors.affiliation: Department of Experimental Psychology, Utrecht University, 3584 CS Utrecht, The Netherlands, Department of Psychiatry and Mental Health, University of Cape Town, 7925 Cape Town, South Africa, and Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, South Africa.
authors.forename: Jack
authors.initials: J
authors.lastname: van Honk
mesh_terms: D000328:Adult; D000679:Amygdala / Q000503:physiopathology*; D003214:Conditioning, Classical / Q000502:physiology*; D004644:Emotions / Q000502:physiology; D005239:Fear / Q000502:physiology*; D005260:Female; D006801:Humans; D008568:Memory / Q000502:physiology; D013216:Reflex, Startle / Q000502:physiology*; D055815:Young Adult
keywords: amygdala; basolateral; fMRI; fear conditioning; lesion; startle