Cardiovascular System and Physical Activity Flashcards

Question

What did Chhabria et al. (2020) find?

Answer 1

Again found high blood glucose impairs neurovascular function in zebrafish by adding mannitol to the tank robust responses to light flash in Mannitol group

Answer 2

It validated the use of zebrafish to understand how conditions like diabetes might impact upon brain health and this is a stepping stone to understanding how this might play out in cognitive decline

Answer 3

The brain controls cardiovascular function in a way which bring in many different brain areas Although ultimately you have hindbrain areas that control breathing and can regulate heartrate, these regions receive input from a much wider brain network This could explain why heart rate may be continually elevated in a defence mode, in a situation of chronic stress Seemingly have a direct route in the brain

Answer 4

Brain circuits controlling cardiovascular function do so via activation of the autonomic nervous system These circuits receive input from cortical and subcortical systems and are responsive to a wide range of physiological and psychological stimuli Physiological: body temperature, blood pressure, blood oxygenation Psychological: stressors (external stimuli, cognitive-affective processes) The continued presence of stressors can increase the presence of cardiovascular risk factors and lead to cardiovascular disease Behavioural responses may relate directly to cardiovascular responses e.g. if stressed, might not engage in sufficient levels of physical activity= reduced activity= exacerbates cardiovascular function or eating behaviour as well see diagram in lecture

Answer 5

Does cardiovascular function feedback more immediately to brain systems?

Answer 6

Visceral (internal organ) sensation and interoceptive input

Answer 7

Ongoing sensory input relating to its own internal status The brain receives ongoing input regarding body state via visceral sensory afferents and via sensing of blood-borne chemicals This underpins interoceptive input to brain systems at multiple levels Brain is aware of the cardiac cycle, what your heart rate is, it regulates heart rate but then the sensation of that sort of thing e.g. the sensation of the current state of digestion, this information is going back into the brain both through direct nervious system signalling, but also through the presence of blood borne chemicals as well, so oxygenation levels of the blood is something the brain is aware of

Answer 8

Inflammation and indications of sickness or disease, so if there is systemic inflammation in the body that might occur in repsonse to injury or infection, the brain is aware of that, it gets that information and then it will alter behaviour in order to cope with that

Answer 9

Giving an individual sensory stimulation and the way in which particualr regions of the brain respond to that depend on exactly what point of the cardiac cycle the arrival of that sensory input is

Answer 10

Have the same interoceptive information coming from the gut , stuff to do with the activation of smooth muscle cells and things relationg to measures e.g. glucose measures in the blood, but the interaction between the brain and the gut is actually complicated because as well as the physiological/biological processes of digestion that are happening in the gut, there is also the gut microbiota e.g. flora and fauna that exist in the gut that help or hinder digestion, as they release chemicals that can get into the blood stream that can influence behaviour through the brain, we are to some extent behvaing at the will of the gut bacteria we have

Answer 11

Could be due to physiological changes e.g. angiogenisis- the development of blood vessels, could relate to improvments in blood flow in the brain, improvements in plasticity These changes connect body health and brain health

Answer 12

Must think about other pathways involved We know exercise alters domapine signalling, this affects reward circuitry in the brain, might change the way you respond to aversive or rewarding stimuli and that changes behaviour which plays out in different ways in terms of cogntive function, it hard to know.

Answer 13

Exercise alters DA signalling to increase reward related responses – buffering the effects of aversive stimuli If you are more resilient to aversive stimuli, you may find that it impacts on the way that stress can feed through physiological responses and potentially propagate things around cardiovascular disease so the reward/aversive response modulation by exercise can affect different things which is separate to the way exercise might just affect oxygenation of blood in the brain

Answer 14

Because many studies do not include consideration of reward/dopamine related effects of physical activity e.g. Stimpson et al. (2018)

Answer 15

Exercise augments/bolsters negative feedback in the HPA axis It's been found that the critical factor for the termination of a stress response in the HPA axis is negative feedback, more effective negative feedback should in theory enable you to limit stress responses and contain them more effectively Exercise reduced the neural and cortisol response to a stressful stimulus The magnitude of mood and endocrine changes observed correlated with brain activation magnitude. This could be what exercise is doing, dampening down the stress response - Zschucke et al. (2015)