title: Stress-induced neuroplasticity: (mal)adaptation to adverse life events in patients with PTSD--a critical overview.
abstract: Stress is an adaptive response to demands of the environment and thus essential for survival. Exposure to stress triggers hypothalamic-pituitary-adrenocortical (HPA) axis activation and associated neurochemical reactions, following glucocorticoid release from the adrenal glands, accompanied by rapid physiological responses. Stimulation of this pathway results in the activation of specific brain regions, including the hippocampus, amygdala and prefrontal cortex which are enriched with glucocorticoid receptors (GRs). Recent findings indicate that the activation of GRs mediates the regulation of the brain-derived neurotrophic factor (BDNF). BDNF is crucial for neural plasticity, as it promotes cellular growth and synaptic changes. Hence stress-induced activation of these pathways leads to neuroplastic changes, including the formation of long-lasting memories of the experiences. As a consequence, organisms can learn from stressful events and respond in an adaptive manner to similar demands in the future. Whereas an optimal stress level leads to enhancement of memory performance, the exposure to extreme, traumatic or chronic stressors is a risk factor for psychopathologies which are associated with memory impairment and cognitive deficits such as posttraumatic stress disorder (PTSD). In this review article, we will outline the implications of stress exposure on memory formation involving the role of glucocorticoids and BDNF. Within this context, potential adverse effects of neuroplastic alterations will be discussed using the example of PTSD.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Tuebingen, Calwerstr. 14, 72076 Tuebingen, Germany. Electronic address: Saskia.Deppermann@med.uni-tuebingen.de.
authors.forename: S
authors.initials: S
authors.lastname: Deppermann
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Tuebingen, Calwerstr. 14, 72076 Tuebingen, Germany. Electronic address: Helena.Storchak@med.uni-tuebingen.de.
authors.forename: H
authors.initials: H
authors.lastname: Storchak
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Tuebingen, Calwerstr. 14, 72076 Tuebingen, Germany; Graduate School LEAD, University of Tuebingen, Europastr. 6, 72072 Tuebingen, Germany; Cluster of Excellence CIN, University of Tuebingen, Otfried-Mueller-Str. 25, 72076 Tuebingen, Germany. Electronic address: Andreas.Fallgatter@med.uni-tuebingen.de.
authors.forename: A J
authors.initials: AJ
authors.lastname: Fallgatter
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Tuebingen, Calwerstr. 14, 72076 Tuebingen, Germany. Electronic address: Ann-Christine.Ehlis@med.uni-tuebingen.de.
authors.forename: A-C
authors.initials: AC
authors.lastname: Ehlis
mesh_terms: D000223:Adaptation, Psychological; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D008016:Life Change Events; D009473:Neuronal Plasticity / Q000502:physiology*; D013313:Stress Disorders, Post-Traumatic / Q000150:complications / Q000473:pathology / Q000523:psychology; D013315:Stress, Psychological / Q000473:pathology / Q000503:physiopathology*
chemical_list: D019208:Brain-Derived Neurotrophic Factor
keywords: BDNF; HPA axis; memory consolidation; neuroplasticity; posttraumatic stress disorder; stress