Effects of stressful life events on human brain structure: A longitudinal voxel-based morphometry study

Abstract

Although stressful life events (SLEs) have been associated with an increased risk of illness and mental disorder, their impact on brain anatomy remains poorly understood. Using a longitudinal design, we tested the hypothesis that SLEs are significantly associated with changes in gray matter volume (GMV) in brain regions previously implicated in post-traumatic stress disorder (PTSD) in a group of clinically healthy adults. Magnetic resonance imaging was used to acquire an anatomical scan from 26 subjects (13 males and 13 females; mean age ± SD: 25.2 ± 4.3 years), with no psychiatric diagnosis, at two time points with a 3-month interval. Voxel-based morphometry was used to examine an association between SLEs and gray matter changes during this period. The number of SLEs was associated with a decrease in GMV in the anterior cingulate, hippocampus, and parahippocampal gyrus (p < 0.001). In contrast, there were no areas where the number of SLEs was associated with an increase in GMV. These results provide evidence that, in adults with no formal psychiatric diagnosis, SLEs are associated with GMV decreases in a subset of regions implicated in PTSD, and that these alterations can be observed within a period as short as 3 months.

Lower anterior cingulate volume in seriously violent men with antisocial personality disorder or schizophrenia and a history of childhood abuse

“…The AC is highly vulnerable to stress-related changes in noradrenergic activity (Hermans et al, 2011) and, like the hippocampus, shows grey matter loss following a variety of stressful conditions, including childhood adversity, in individuals with or without a PTSD diagnosis (Ansell et al, 2012;Dannlowski et al, 2012;Karl et al, 2006). Although the current study is unable to conclusively inform about the direction of causality in the observed relationship between AC volume and psychosocial deprivation/abuse, a number of studies have clearly shown AC grey matter loss in people experiencing stressful life events and cumulative life adversities with no psychiatric diagnosis (Ansell et al, 2012;Ganzel et al, 2008;Papagni et al, 2011), as well as in animals following exposure to stress (Cerqueira et al, 2005;Kassem et al, 2013).…”

Brain structural plasticity in survivors of a major earthquake

“…6 Furthermore, the findings from these studies indicated that grey matter atrophy could only be observed 3 months after stressful life events. 6 A report that functional brain alterations have been observed in healthy survivors as early as 25 days after a major earthquake 7 raises the question of whether acute neuroanatomical differences could also be detected earlier than 3 months following major emotional stress. To address this issue, we used optimized voxel-based morphometry (VBM) to compare the grey matter volume of physically healthy survivors of the Wenchuan earthquake to that of healthy controls living in the same geographical region who had undergone imaging before the earthquake.…”

“…To date, few studies have examined the association between life stress and brain structure in adult participants without a history of psychopathology or brain disorder. [3][4][5][6] Moreover, individuals recruited for previous studies had experienced different types of stress-related events, including illness or injury, death of a close friend or relative, unemployment and the ending of important relationships, which might have variable effects on the brain. 6 Furthermore, the findings from these studies indicated that grey matter atrophy could only be observed 3 months after stressful life events.…”

“…[3][4][5][6] Moreover, individuals recruited for previous studies had experienced different types of stress-related events, including illness or injury, death of a close friend or relative, unemployment and the ending of important relationships, which might have variable effects on the brain. 6 Furthermore, the findings from these studies indicated that grey matter atrophy could only be observed 3 months after stressful life events. 6 A report that functional brain alterations have been observed in healthy survivors as early as 25 days after a major earthquake 7 raises the question of whether acute neuroanatomical differences could also be detected earlier than 3 months following major emotional stress.…”

False positive rates in Voxel-based Morphometry studies of the human brain: Should we be worried?

“…Over the past 15 years, VBM has been used successfully to investigate a wide range of neurological and psychiatric disorders including, but not limited to, Alzheimer's disease (Li et al, 2012), Parkinson's disease (Pan et al, 2013), multiple sclerosis (Lansley et al, 2013), unipolar (Lai, 2013) and bipolar (Selvaraj et al, 2012) depression, anxiety disorders (Radua et al, 2010) and psychosis (Honea et al, 2005;Bora et al, 2011Mechelli et al, 2011. In addition, VBM has been used to compare groups of healthy subjects who differ with respect to biological or environmental variables of interest such as age (Kennedy et al, 2009;Takahashi et al, 2011), gender (Takahashi et al, 2011;Sacher et al, 2013), number of spoken languages (Mechelli et al, 2004), and exposure to stressful life events (Papagni et al, 2011).…”