chemical regulation of behaviour (EM) Flashcards
Name 8 neurotransmitters
- Adrenaline
- Noradrenaline
- Dopamine
- Serotonin
- GABA
- Acetylcholine
- Glutamate
- Endorphins
What is adrenaline?
- Fight or flight neurotransmitter
When is adrenaline produced?
- Produced in stressful/exciting situations
What are the effects of adrenaline?
- Increases heart rate and blood flow , which leads to a physical boost and heightened awareness
What is noradrenaline?
- Concentration neurotransmitter
What does noradrenaline affect and what is it involved in?
- Attention and responding actions in the brain
- Involved in fight or flight response
What does noradrenaline do?
- Contracts blood vessels, increasing blood flow.
What is dopamine?
- Pleasure neurotransmitter
What does dopamine cause?
- Feelings of pleasure, addiction, movement and motivation
What does dopamine lead to/
- People repeating the behaviours that cause the body to produce dopamine, this has positive and negative aspects
What is serotonin?
- Mood neurotransmitter
What does serotonin do?
- Contributes to wellbeing and happiness
- Helps the sleep cycle
- Aids in digestive system regulation
What is serotonin affected by?
- Exercise
- Light exposure
What is GABA?
Bonus points if you name what GABA stands for
- Gamma aminobutyric acid
- Calming neurotransmitter
What does GABA do?
- Calms firing nerves in the CNS
- Contributes to motor control and vision
What do high levels of GABA cause?
- Improvement of focus
What do low levels of GABA cause?
- Anxiety
What is acetylcholine?
- Learning neurotransmitter
What is acetylcholine involved in?
- Thought
- Learning
- Memory
- Attention
- Awakening
What does acetylcholine do?
- Activates muscle action within the body
What is glutamate?
- Memory neurotransmitter
- (Most common neurotransmitter)
What is is glutamate involved in?
- Learning
- Memory
What does glutamate do?
- Regulates development and creation of nerve contacts
What are endorphins?
- Euphoria neurotransmitters
When are endorphins released?
- Exercise
- Excitement
- Sex
What do endorphins do?
- produce a sense of wellbeing and euphoria which reduces pain
Name some advances made in neuroscience
- The development of optogenetic methods in neuroscience
- Utility of using optogenetics to study behaviour
- Use of optogenetic methods to study neurotransmitter systems in the brain
Where does eating/appetite originate from in the brain?
- Hypothalamus
- Arcuate nucleus
Where does fear originate from in the brain?
- Amydala
Where does stress/anxiety originate from in the brain
- Hypothalamus
- pituitary circulation
- CRH
What is CHR?
What is the function of CHR?
How many amino acids does it consist of?
Where is it secreted from?
- Neuropeptide hormone
- Regulates neuroendocrine, sympathetic, and behavioural functions in response to stress.
- 41 amino acids
- Paraventricular nucleus (PVN) and hypothalamus
What excites neuroscientists about optogenetics?
- Control over defines events within defines cell types at defined times
State the definition of optogenetics
- The combination of genetics and optics to control well defines events within specific cells of living tissue.
What does optogenetics include?
- The insertion in cells of genes that confer light responsiveness
- Technologies for delivering light deep into the brains of freely moving mammals, for targeting light sensitivity to cells of interest and for assessing specific readouts/effects of this optical control.
What are channelrhodopsins?
- Nonspecific cation channels that depolarize upon blue light illumination. These light-gated ion channels (chromophore, vit-A) were isolated from green microalgae of the genus, Chlamydomonas. Structurally, they have a seven-transmembrane region and a C-terminal extension.
- They serve as sensory photo receptors in uni-cellular green algae , controlling phototaxis ( movement in response to light)
- A sub family of retinylidene proteins.
Name the two channelrhodopsins found in the algae species ‘Chlamydomonas reinhardtii’.
- Channelrhodopsin-1 (ChR1)
- Channelrhodopsin-2 (ChR2)
How do channelrhodopsins function in algae?
- As visual proteins directing the algae towards/away from a light source, or to find light conditions that are optimal for photosynthetic growth
What does light absorption trigger, in relation to CHR?
- A subsequent conformational change of the protein and gating of the channel.
Describe the method for manipulating specific neuronal populations using light
(the basis of optogenetics)
1 - Piece together the genetic construct (transgene)
2 - Package construct into virus
3 - Inject virus into brain structure
How long does it take for ChR2 to be expressed fully in transduced neurons?
- 2 weeks
What is AAV ( adeno associated virus)?
- A group of small viruses that belong to the genus dependoparvovirus
Is AAV biologically non inert or inert?
- On its own AAV is biologically inert
Is AAV a replicating or non replicating virus?
- Non replicating
What is transduction?
- The process whereby foreign DNA is introduced into another cell via a viral vector
List the method of a transduction.
1 - Specific genes of an invasive virus are removed and replaced by a transgene of interest. ( For example ‘ChR2 transgene’)
2 - Virus is injected into the brain
3 - The virus penetrates the nucleus and inserts the transgene into the cells DNA
4 - The transgene is transcribed and the target protein (for example , ChR2 protein’ is synthesised.
Do transduced neurons respond to light?
Neurons expressing ChR2
- Yes
- EXTRA INFO - Each pulse of blue light causes the neuron to fire
Neurons that don’t express ChR2 respond to light (T/F)
- False
- EXTRA INFO - Each pulse of blue light does not cause the neuron to fire.
What is halorhodopsin?
- A light-gated ion channel that is permeable to chloride.
What is the ultimate goal when using optogenetics to study behaviour?
- To study the casual relationships between the activity of targeted brain pathways and the behaviour they may regulate or control.
What is the physiological function of the amygdala?
- Emotional memory
- Fear
- Regulating hippocampal function
What does the amygdala comprise of?
- The basolateral complex
What does the basolateral complex comprise of?
- Lateral nuclei
- Basal nuclei
- Accessory basal nuclei
