4B - GBA

Question 1

Enteric Nervous System

Answer 1

Network of nerves in the gut. It is responsible for regulating digestion by controlling muscle movements in the intestines, releasing digestive enzymes, and absorbing nutrients
ENS coordinates the muscle contractions that moves material along the digestive tract; regulates gastric acid secretion; regulate gut hormones; interacts with the immune system

Question 2

Gut-Brain Axis (GBA)

Answer 2

• Refers to the connection that exists between the CNS and the ENS
• Enables bidirectional communication between the brain and the GI tract. This means that communication can occur in both directions, from brain to gut and gut to brain
• The bidirectional communication that occurs between the CNS and the ENS happens via the vagus nerve and the gut microbiota

Question 3

Vagus Nerve

Answer 3

• Column of nerve fibres that connects the brain and the gut
• Bidirectional
  
  • 10-20% of nerve fibres convey information from the brain to
    the gut (efferent pathways)
  • 80-90% of nerve fibres convey information from the gut to the
    brain (afferent pathways)

Question 4

Gut Microbiota

Answer 4

These microbes digest the components of our food to provide their own nutrients while also simultaneously providing us with energy and nutrients

Gut microbiota are also involved in the production of some neurotransmitters (such as GABA, serotonin and dopamine), which can affect the concentration of related neurotransmitters in the brain

This can have effects within the ENS itself as well as enabling fast signals to be transmitted to the brain via the vagus nerve

Question 5

Impact Of Stress

Answer 5

High Levels Of Stress + Increased Cortisol Levels = Changes in gut microbiota (associated with anxiety and depression)

Therefore, unhealthy microbiome cannot produce and release adequate levels of neurotransmitters

Question 6

Gut-Related Diseases

Answer 6

Such as irritable bowel syndrome and inflammatory bowel disease

There are potential links between the presence of these gut-related diseases and the presence of anxiety and depression symptoms (Abautret-Daly et al., 2017, Whitehead et al., 2002)

Therefore, experiencing a gut-related disease may increase the likelihood of experiencing a mental illness

Question 7

Ethical Concepts

Answer 7

• beneficence
• non-maleficence
• justice
• integrity
• respect

Question 8

Ethical Guidelines

Answer 8

• withdrawal rights
• deception
• voluntary participation
• debriefing
• informed consent
• confidentiality