Introduction to brain and behaviour Flashcards
What influences behaviour?
(4 things)
Behavioural traits due to evolutionary and genetic influences
Behavioural traits due to environmental and social influences (eg. is a person displaying a particular behaviour because the others around them are doing this behaviour)
Behaviour based on current motivational state of the animal. (eg. if an animal is hungry/ stressed what are they more or less likely to do)
Behavioural traits based on previous experience
What is brain and behaviour?
The processes in the brain that lead to a particular behaviour
A biological perspective on how the brain controls behaviour
Requires thinking about and understanding brain function on a number of levels
A hierarchy of organisation
- Levels are connected
- Any manipulation at any level can change the function at other and at all levels of the hierarchy
We can change how the cells and brains are working and then can interpret the particular behaviour of the whole organism- changing any levels can change the outcome/ behaviour.
Levels of structures
- Whole brain
- Brain Circuits
- Brain Regions
- Cells (neurons and glia)
- Organelles (synapses/axons)
- Protein complexes
- Proteins
- Genes
Using a perspective that we are made by building blocks that are perhaps different cells that carry a specific and unique code. These cells are creating different organs and different regions and we have the brain with different circuits that are talking to one another. There is constant communication.
How is our genetic makeup and our brains dictating behaviour?
Our behaviour, environment, experiences also have an impact on our genes and gene expression. In turn, these change our brains which can change our behaviour.
Constant interaction of our biology, building blocks and hierarchy with our environment and then our environment feeds back and its a constant interaction.
The building blocks of the brain
Neurodevelopment Genetics
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Neurophysiology:
Neurotransmission & Neuromodulation
Molecular aspects of L&M
Pain
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Behaviour:
Social behaviour
Sleep & circadian rhythms
Typical & atypical
Functioning
Facts about the brain
- Brain weight at birth weighs about 350g whereas in adulthood it is about 1300g
- There are about 85 billion neurons and trillions of synapses in the mature brain
- At the peak of neurogenesis, 250,000 neurons are born per minute!
Prenatal Development Stages
- Germinal Stage (1-2w)
- Embryonic Stage (3-8w)
- Fetal Stage (9-38w)
Prenatal Development Overview
All the processes begin mostly before birth
Germinal is a primitive, basic stage
Embryonic stage- all action taking place occurs after 3rd week of gestation. All organs of body are starting to form until week 9 which is fetal stage.
Germinal stage
- The nuclei of the egg and the sperm fuse to form a zygote. (ovum is zygote- fertilised egg)
- Zygote starts to divide at 12h, by a process called cleavage, to form a cluster of homogeneous cells - morula.
- The morula continues to divide to form a blastocyst (200-300 cells).
(blastocyst- collection of different cells that have already travelled down the fallopian tube)
When does the embryonic stage begin?
Once implantation in the uterus takes place, the embryonic stage begins.
Embryonic Stage: Gastrulation
- initially?
- what forms?
- what happens structurally?
- Initially – embryonic disc
- Uneven rate of cell development forms three distinct layers:
1. Ectoderm (upper)
2. Mesoderm (middle)
3. Endoderm (bottom) - The ectoderm will fold in itself to form the neural tube which will eventually become the nervous system
(The differentiation of different layers of these formation. The way these layers differentiate dictates what is going to become the brain, the body and so on.)
Process of gastrulation
When the neural crest starts to swallow, it kind of falls on itself and forms a hole in the centre which is called the central canal.
The neural tube is really what is going to become the brain.
Formation of the Nervous System
Swelling in middle
Then it falls on itself and starts to zip up
Top of neural tube will start to develop and become the brain where as the bottom part starts to create the midbrain and the hindbrain and then the spinal cord.
Neural tube starts to shape itself and differentiate and then look like a brain. All of these processes are dictated by genes.
Neural Tube Defects
Interaction between and influences from?
Constant interaction between what our genes dictate and the environment. The environment for the embryo is the placenta and the mums body. Whatever stimuli mums process or whatever they ingest (food, alcohol, nicotine) is transferred through the placenta and umbilical cord into the body.
