Default Mode Network Flashcards
What is the DMN and what roles does it take part in?
It is a task independent network,
Self referencing, Tom, daydreaming, Mind wandering
What is Riechle’s theory regarding Brains dark energy, and what prompted it?
Our brain consumes 20% of oxygen consumption and only 5% more when activated in a task. Riechle suggested this is increases the stability and reactivity of our mind as it predicts the future and it’s needs. This all happens unconsciously.
What did Masons study reveal about Novel and practiced tasks?
That practiced task allow the mind to wonder reflected by Bold in MRI
How did Buckner and Carroll prove the the DMN is involved in self referencing?
By asking participants to Remember, Prospect or use ToM and record the area of the brain stimulated. It happened to be the DMN via the medial temporal lobe
How are Riechle and Buckner & Carroll’s theories compatible?
Riechle believed the process was unconscious, Buckner and Carroll saw it as conscious. It is possible that it activated consciously through self-referential tasks and unconsciously in the background
What is BOLD and how does it work?
Neurons require oxygen and glucose to fire, the oxygenated blood is then deoxygenated and is no longer magnetic.
Blood Oxygenated Level Dependent signal-Indirect measure
2 seconds to react and raise up, 5 second to peak, 5 sec plateua, 4-6 sec to fall back to baseline- this means 2 things, 1- Bold is a slow measure, 2- A baseline is needed to make comparisons
What was the original use of Fmri?
To measure task based activities, Gunsnard and Riechle then looked at this baseline specifically.
What did Fox et al show in their fmri study?
The brain was organised into networks and that the task orientated and rest orientated networks were anti-correlated- known as task positive and task negative
Task positive on the outside and task negative middle
They also found that the brain switches automatically between these states at rest.
How is the DMN related to psychopathy?
DMN hyperactivity in schizophrenia, depression, ADD and autism. Schizo patients unable to inhibit the DMN - therefore Increased self ref =
less capacity for cognitive processing,
less efficiency of cognitive processing and increased self ref- vision cycle
Killingsworth and Gilbert found what with regards to mind wandering?
A wandering mind is an unhappy mind.- Mind wondered regardless of what they were doing, nature of activity only small impact on if mind wondered or no impact on if the wind wondered to pleasure or not.
Where do we find the “self” in the brain?
MPFC=
Psychological sense of self-Ventral mpfc-
Personal Dorsal Mpfc-
Socail self- Posterior cingulate/ precuneus- somatic self and episodic memory integration of somatic and affective
