Kevin Hilbert1, Ulrike Lueken2, Katja Beesdo-Baum2. 1. Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany; Neuroimaging Center, Technische Universität Dresden, Dresden, Germany. Electronic address: Kevin.Hilbert@tu-dresden.de. 2. Institute of Clinical Psychology and Psychotherapy, Technische Universität Dresden, Dresden, Germany; Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.
Abstract
BACKGROUND: Research on the neurobiological basis of Generalized Anxiety Disorder (GAD) has considerably expanded in recent years. However, many studies investigated different domains and used different methods and paradigms. Therefore, this review aims to integrate the findings to date and to identify the core correlates of neurobiological underpinnings of GAD discovered so far. METHODS: We conducted a systematic review of original papers investigating neural correlates, connectivity, or structural changes as well as reporting changes in the serotonergic system, noradrenergic system and cortisol levels in DSM-IV-defined GAD samples until December 2013. RESULTS: Studies have identified abnormal amygdala and prefrontal cortex activation in patients and decreased functional connectivity between these areas. Furthermore, studies showed increased gray matter volume and decreased structural connectivity between these structures. Neuroendocrine findings are less consistent, but increased reactivity of the noradrenergic system and perpetuations in the cortisol secretion have been reported. LIMITATIONS: Only studies on DSM-IV defined Generalized Anxiety Disorder which employed a group comparison were included. CONCLUSIONS: Current research suggests a distinct set of neurobiological alterations in Generalized Anxiety Disorder. However, future research on the interaction between these structures and systems and on the specificity of these findings in relation to other mental disorders is urgently needed.
BACKGROUND: Research on the neurobiological basis of Generalized Anxiety Disorder (GAD) has considerably expanded in recent years. However, many studies investigated different domains and used different methods and paradigms. Therefore, this review aims to integrate the findings to date and to identify the core correlates of neurobiological underpinnings of GAD discovered so far. METHODS: We conducted a systematic review of original papers investigating neural correlates, connectivity, or structural changes as well as reporting changes in the serotonergic system, noradrenergic system and cortisol levels in DSM-IV-defined GAD samples until December 2013. RESULTS: Studies have identified abnormal amygdala and prefrontal cortex activation in patients and decreased functional connectivity between these areas. Furthermore, studies showed increased gray matter volume and decreased structural connectivity between these structures. Neuroendocrine findings are less consistent, but increased reactivity of the noradrenergic system and perpetuations in the cortisol secretion have been reported. LIMITATIONS: Only studies on DSM-IV defined Generalized Anxiety Disorder which employed a group comparison were included. CONCLUSIONS: Current research suggests a distinct set of neurobiological alterations in Generalized Anxiety Disorder. However, future research on the interaction between these structures and systems and on the specificity of these findings in relation to other mental disorders is urgently needed.
Authors: Tim Klucken; Jan Schweckendiek; Carlo Blecker; Bertram Walter; Yvonne Kuepper; Juergen Hennig; Rudolf Stark Journal: Soc Cogn Affect Neurosci Date: 2014-08-19 Impact factor: 3.436
Authors: Uraina S Clark; Lawrence H Sweet; Susan Morgello; Noah S Philip; Ronald A Cohen Journal: Brain Imaging Behav Date: 2017-06 Impact factor: 3.978
Authors: Kevin Hilbert; Daniel S Pine; Markus Muehlhan; Ulrike Lueken; Susann Steudte-Schmiedgen; Katja Beesdo-Baum Journal: Psychiatry Res Date: 2015-10-13 Impact factor: 3.222