Week 3

Question 1

What is the default mode network?

Answer 1

The DMN consists of a group of interconnected brain structures, including the:

• hippocampus
• medial prefrontal cortex
• posterior cingulate cortex

These interconnected regions are proposed to support self-referential processing, episodic
memory, theory of mind, etc.

Question 2

Which 3 subsystems can the DMN be divided into?

Answer 2

1) Core subsystem: anterior medial prefrontal cortex and posterior cingulate cortex

2) medial temporal subsystem: hippocampus, parahippocampal cortex, retrosplenial cortex, posterior inferior parietal lobe, and ventromedial prefrontal cortex

3) Dorsal Medial subsystem: Dorsal medial prefrontal cortex, temporoparietal junction, lateral temporal cortex and temporal pole

Question 3

How does the study by Brewer and colleagues show that that mindfulness can alleviate mind wandering ?

Answer 3

Less activation in the medial prefrontal and posterior cingulate cortices in long term meditators, suggesting a link between the Default Mode Network and mind wandering.

Question 4

What did the systematic review by Feruglio conclude?

Answer 4

lower activation in the DMN regions, such as the posterior cingulate cortex and the middle
temporal gyrus

–> The authors therefore concluded that mindfulness has important implication in promoting mental health, such as PTSD, depression and anxiety disorders

Question 5

What are some suggestions for observing changes in individual

Answer 5

• cortical thickness in the anterior DMN due to enhanced involvement of emotional regulation during mindfulness practice.
• thinner cortical thickness could be found in the posterior DMN as improved self-referential processing could happen after mindfulness practice.

Question 6

What is the insula said to be associated with?

Answer 6

• supports moment awareness of the body’s internal and visceral states, such as respiration and heart rate
• also involved in emotional self-awareness

Question 7

What did Lazar and colleagues examine in a study in 2005 and what did they find?

Answer 7

Grey matter integrity

• Greater cortical thickness was found in:

a) the right dorsolateral prefrontal cortex, which is
associated with sustained attention and cognition-emotion integration.

b) the right insula, which is associated with interoceptive awareness.

Question 8

What did the study by Farb et al show?

Answer 8

Farb and colleagues discovered a greater IA-related functional plasticity in the middle and anterior insula in the MBSR group, regions that
support present moment awareness.

Question 9

What did the study of Pernet and colleagues find?

Answer 9

That only the the right anterior ventral part of the insula showed activation between all studies from the meta-analysis performed

Question 10

Difference between left and right amygdala?

Answer 10

The right amygdala is related to negative emotions and immediate behavioral response, while the left side is associated with positive emotions and memory

Question 11

What did Hölzel et al find in their 2010 longitudinal study?

Answer 11

reduction in perceived stress was associated with a decreased grey matter density in the right basolateral amygdala

Question 12

What were the key findings of Taren et al. 2013 study?

Answer 12

A negative association between dispositional mindfulness and regional grey matter volume in the right amygdala only, after controlling for age, gender, total grey matter volume, depressive symptomatology and neuroticism

Question 13

Difference between top down and bottom up processing?

Answer 13

Bottom-up and top-down processing are two different ways of making sense of stimuli. In bottom-up processing, we allow the stimulus itself to shape our perception, without any preconceived ideas. In top-down processing, we use our background knowledge and expectations to interpret what we see.

Question 14

What is the posterior and anterior cingulate cortex associated with?

Answer 14

posterior: attention regulation, conscious
awareness and emotional regulation.

anterior: executive attention, self-regulation, focused problem-solving, and adaptive behavioral response

Question 15

What are the findings of Tang #s 2020 study?

Answer 15

Greater grey matter volume in the ventral posterior cingulate cortex

Question 16

Other findings regarding Mindfulness and Cingulate Cortex?

Answer 16

• Lower pain sensitivity in meditators than in controls
• Across all subjects, lower pain sensitivity was associated with thicker cortex in painrelated brain regions, including the ACC, bilateral para-hippocampal gyrus and the anterior insula
• Meditators had thicker cortex in the dorsal anterior cingulate and in the bilateral secondary somatosensory cortex (SII)
• Years of mediator experience was associated with thicker grey matter in the ACC
• Hours of experience predicted more grey matter bilaterally in the lower leg area of the primary somatosensory cortex and the hand area in the right hemisphere
• The authors suspect enhanced awareness and control of emotions, including pain, are associated with the ACC after meditation

Question 17

Why is the bottom-up network called bottom-up?

Answer 17

Because the flow of the information through this network is directed from the primary sensory cortices that respond to external stimuli towards the frontal cortex.

Question 18

What was one of the main findings by Gusnard and Raichle?

Answer 18

PET imaging demonstrated that some brain areas (particularly posterior cingulate cortex and the posterior midline of the brain) show decreases when we are engaged in a goal-directed task and the greatest consumption of metabolic energy whilst we are supposedly at rest.

Question 19

What is THE main finding of the Gusnard and Raichle paper?

Answer 19

No matter the nature of the cognitive task, these areas (the midline structures, including medial
prefrontal cortex and the posterior cingulate) were active in the absence of a task. Furthermore, as the attentional demand of the tasks increase, the activity in the resting state regions is further decreased.

Question 20

What did the paper by Fox and colleagues in 2005 demonstrate?

Answer 20

that the human brain is intrinsically organised into dynamic anti-correlated functional networks.

anti-correlated meaning when one goes up, the other one goes down.

Question 21

What is the positive network?

Answer 21

The positive network corresponds to the activity increases observed in the lateral, frontal and parietal regions during goal-directed attention and
working memory processes commonly recruited by cognitive task paradigms.

Question 22

What is the negative network?

Answer 22

The negative networks are the regions that attenuate activity during attention-demanding cognitive tasks.

Question 23

Where are the positive and negative network located?

Answer 23

• The positive network is primarily localised on the outside of the brain including dorsolateral prefrontal cortex, or DLPFC, frontal eye fields, abbreviated as FEF, inferior parietal lobule and supplementary motor areas.
• The negative network, as we saw before, is primarily located in the midline of the brain with the main
  nodes in medial prefrontal cortex, posterior cingulate and the precuneus.

Question 24

Which one is referred to as the default network and why?

Answer 24

• The negative network

Because it is activated by the default when we are not engaged in goal-directed cognitive activity.

Question 25

What did Fox and colleagues find with regards to the two networks in their resting state?

Answer 25

That during the resting state itself the brain is constantly shifting and fluxing between the two networks.

Question 26

What did Fox et al find regarding changes within the same network?

Answer 26

There are fluctuations in the
correlations between different nodes
of the task-negative network

Question 27

What are the names of the two attentional systems?

Answer 27

• a bilateral dorsal attentional system involved in a voluntary or controlled orienting of attention (top-down)
• a right lateralised ventral attentional system involved in reorienting attention in response to salient sensory stimuli (bottom up)

Question 28

Which system helps to switch the attention between the two networks (top down and bottom up)?

Answer 28

• the overlap between the two!!

Question 29

What are the characteristics for top down vs. bottom up processing?

Answer 29

Dorsal attention network (top-down):

• voluntary
• goal-directed
• selective
• focused
• effortful/controlled

Ventral attention network (bottom-up):

• involuntary
• stimulus/salience-driven
• receptive
• open to periphery
• effortless/automatic

Question 30

What do the dorsal top-down and the ventral bottom-up attention networks correspond to?

Answer 30

Orienting = dorsal top-down

Alerting = ventral bottom-up

Question 31

There are different models regarding the attentional networks. What is important to keep in mind?

Question 32

Which system feeds which? (orienting & alerting)

Answer 32

Orienting feeds alerting

• Altering = Influenced by what is salient or important to us, like biological survival, our desires, our priorities.
• Influenced by the way we experience and perceive the world around us and in turn feeds into what is salient for our ventral attentional system.

Question 33

What is another word for the default mode network?

Answer 33

negative network
task-independent network

Question 34

What were the main findings on mind wandering by Killingsworth and Gilbert, 2010, who were collecting data on mind wandering via an app?

Answer 34

• people’s minds wandered frequently regardless of what they were doing, except for when they were making love
• the nature of the activity had only a modest impact on whether their minds wandered and had almost no impact on the pleasantness of the topics to which their minds wandered

Question 35

Which 4 stages does the Focused attention meditation model consist of?

Answer 35

• mind-wandering
• awareness of mind wandering
• shifting of attention
• sustained attention.

Question 36

Which phases of the 4 stages of the focused attention meditation model correlate with what brain networks?

Answer 36

• mind wandering = default mode network
• awareness of mind-wandering, shifting attention back to the meditation object, and sustaining
  it on the object = associated with the attention networks, including executive control areas

Question 37

What are the active brain areas during mind-wandering?

Answer 37

• default mode network regions
• bilateral post-central gyrus and posterior insula (precentral gyrus and supplementary motor areas)