Stress reduction correlates with structural changes in the amygdala

Abstract

Stress has significant adverse effects on health and is a risk factor for many illnesses. Neurobiological studies have implicated the amygdala as a brain structure crucial in stress responses. Whereas hyperactive amygdala function is often observed during stress conditions, cross-sectional reports of differences in gray matter structure have been less consistent. We conducted a longitudinal MRI study to investigate the relationship between changes in perceived stress with changes in amygdala gray matter density following a stress-reduction intervention. Stressed but otherwise healthy individuals (N = 26) participated in an 8-week mindfulness-based stress reduction intervention. Perceived stress was rated on the perceived stress scale (PSS) and anatomical MR images were acquired pre- and post-intervention. PSS change was used as the predictive regressor for changes in gray matter density within the bilateral amygdalae. Following the intervention, participants reported significantly reduced perceived stress. Reductions in perceived stress correlated positively with decreases in right basolateral amygdala gray matter density. Whereas prior studies found gray matter modifications resulting from acquisition of abstract information, motor and language skills, this study demonstrates that neuroplastic changes are associated with improvements in a psychological state variable.

Mindfulness and emotion regulation—an fMRI study

“…The insula is also a key structure for interoceptive awareness (Critchley et al, 2004) and the awareness of emotions (Craig, 2009), and it has been found to undergo structural changes in meditators (Lazar et al, 2005;Hölzel et al, 2010). Increased activity in this region in the mindfulness group could therefore reflect the instructed focus on bodily sensations and emotions.…”

Efeito da Meditação Focada no Estresse e Mindfulness Disposicional em Universitários

“…Também existem evidências de que a meditação ajuda a reduzir a reatividade da amígdala (AM) frente a estímulos emocionais negativos, cujo padrão é precedido por uma maior ativação do córtex pré-frontal dorsomedial e dorsolateral (Lutz et al, 2013). De modo similar, outro estudo mostrou que uma redução da percepção de estresse se correlacionou com uma menor densidade de massa cinzenta na AM direita (Hölzel et al, 2009). Portanto, a meditação parece auxiliar no manejo do estresse devido a uma combinação de mecanismos de regulação atencional e emocional que favorecem que o praticante consiga modular sua percepção e sua resposta às experiências emocionais.…”

Amygdala, Childhood Adversity and Psychiatric Disorders

“…For example, a study showed that Cognitive Behavioral Therapy (CBT, a common behavioral intervention approach particularly effective for depression) administered to depressive patients, was able to reduce amygdala activity and enhance prefrontal activity [95] (Figure 12). Another study suggested that Mindfulness Based Stress Reduction (MBSR) training (commonly known as "meditation") induced changes in perceived stress level as well as in amygdala gray matter density, while larger decreases in perceived stress were associated with larger decreases in amygdala gray matter density [96] (Figure 13). …”