Mindfulness and Brain regions Flashcards
What is the DMN and what does it consist of?
Default Mode Network
hippocampus, MPFC, posterior cingulate cortex
What tasks are the DMN related to?
self-referencing, episodic memory, Tom, autobiographical memory
Mid Wandering
What has Mind Wandering been linked to?
Increased errors in activity
A number of mental disorder
What did Brewer et al find in mindfulness and brain networks?
Meditators with 10 years experience were found to have less mind wandering and decreased activity in the DMN in all types of meditation
What did Ferugillo et al find in their systematic review of mindfulness and mind wandering?
The review found lower MW during meditation in meditators
Reduced activity in the DMN
What roles are the insula responsible for?
Awareness of internal visceral states
Emotional self-awareness
What did Lazar find regarding the brain structure and mindfulness?
He found greater grey matter in the PFC and the right insula, and like Hozel found thickness was associated with length of experience.
Fard found what regarding mindfulness and interception attention?
MSBR group showed greater IA specific functional platisicity (middle and anterior insula) compared to controls.
What did Pernet et al find in their meta-analysis?
In 25 studies the anterior ventral Insula was the only consistently different area between meditatiors and controls.
What are the limitations of Pernet’s meta analysis?
Multiple types of mediations used
Cross sectional studies
Confounders
Lack of observational blinding
What are the key roles in the amygdala?
Part of limbic system
Flight or fight response
Right side related to negative emotion and immediate behavioural response-Left side related to positive emotions and memories
What did Hozel’s longitutadal study of perceived stress and amygdala grey matter find?
MBSR decreased perceived stress and this was associated with decreased grey matter in right amygdala
What did Taren et al find with mindfulness and MRI studies?
By looking at those with dispositional mindfulness they found a negative association in Grey matter volume and right amygdala grey matter volume.
What did Gotink et al find about the amygdala hippocampus grey matter and mindfulness?
Yoga practice was shown to be associated with lower right amygdala volume
Is mindfulness the only reason we may see differences in a study like Gotink et al?
No group interaction, general learning or attention may also impact results.
What roles do the ACC and the PCC exhibit?
attention regulation, conscious awareness and emotional regulation
Elevated PCC implicated in distancing
ACC implicated in executive attention, self-regulation, focused problem solving and adaptive behaviour
What did Tang et al find with regards to Integrative Body and Mind training?
Grey matter volume of the ventral PCC was found
White matter plasticity in ACC and PCC also found
This has been replicated 4 times
What did Grant et al find in Zen meditators?
They exhibited lower pain sensitivity
This was associated with thicker ACC and this was linked to years meditating
Meditators had thicker dorsal anterior cingulate, and secondary somatosensory cortex (SSC)
Hours meditated related to thicker SSC
Where is the hippocampus located, what is it’s function and what can dysfunction lead to??
Medial temporal lobe, emotional regulation and memory as it connects to PFC and Amygdala.
Depression and Anxiety
What role does the hippocampus play in the stress response?
The hippocampal head interacts with both the hypothalamus and the amygdala and so plays a role in stress detection and glucocorticoid release.
What can cortisol do to the hippocampus?
Cortisol damages the hippocampus via the toxic effect- neurodegeneration and neurogenesis, resulting in ineffective negative feedback loop leading to more cortisol.
How important Is the hippocampus to mental health?
Extremely, hippocampal atrophy has been linked to almost all psychopathologies Depression, OCD, ALzehimers, Psychosis, PTSD
What are some mechanisms of the hippocampus that suggest mindfulness would stimulate it?
Attention regulation, Body awareness, Emotional regulation, changing perspectives of the self
What did Hozel find in his VOXEL study?
He found experienced meditators had higher greater grey matter in the right interior Insula and Left inferior temporal gyrus and these were related to experience of mediations, and right hippocampus. But whole brain grey matter was the same.
What did Luders et al find with regards to meditators and brain structure?
In 2009 they found greater grey matter in Right Hippocampus, Right Thalamus, Right orbifrontal cortex
And 2015 meditators found enlarged hippocampus in meditators and male and females had differing results in these areas.
What did Hozel lodgtitudal study find?
Post meditation the subjects showed left hippocampal grey matter increases, but nothing in the insula. Whole brain analysis saw posterior cingulate, temporal-parental junctions and cerebellum
Wells and colleagues lodgtitudal study showed us what?
MBSR increased functional connectivity in DMN less hippocampal atrophy, but this was a small study.
Why are small sample sizes a problem?
hey may produce false positives, they lack generalisability
Greenbergs RCT study was able to show what?
Hippocampal function and volume was looked at, but only function was positively effected via proactive interference tests. However this study was only 4 weeks MBSR.
How can studies in hippocampus and mindfulness be improved?
Active controls so general learning is ruled out, more and larger RCT, Follow ups.
