Basic Knowledge of Early Brain Development (AQA GCSE Psychology)

Neural structures in the womb: brain stem & cerebellum

• The brain stem is the structure that connects the brain to the spinal cord and the cerebellum

• It is responsible for many key functions such as:

  • consciousness

  • breathing

  • blood pressure,

  • sleep

  • heart rate

• Key functions are found in the autonomic nervous system:

  • These are functions that you don’t have control over 

  • Key autonomic functions are involuntary e.g. digestion occurs when food is taken in, sleep will eventually overwhelm you even if you are trying to stay awake

• The brain stem is one of the first areas of the brain to develop and - unlike other areas of the brain which govern higher-order functions (e.g. thinking) - it does not continue to develop further

• The brain stem must be fully formed for other functions to develop as it is the communication route in which the autonomic nervous system operates

• The cerebellum is vital in terms of movement and balance

• It coordinates bodily movements, maintaining posture, muscle tone and voluntary actions

• The cerebellum uses sensory information, for example:

  • It receives messages from the eye muscles about environmental conditions the message could be, ‘I need more light to read by’ the cerebellum can then adjust head movement by turning towards the light source

• The cerebellum also plays a role in some cognitive functions e.g. language and memory

• It takes longer for the cerebellum to develop than the brain stem and is not complete in humans until they reach two years old (Van Essen et al. 2020)

Neural structures in the womb: thalamus & cortex

• The thalamus is an egg-shaped, walnut-sized structure located in the brain’s centre, above the midbrain

• It straddles both hemispheres of the brain i.e. you could slice down the middle of the brain to make two halves

• The thalamus acts as a relay station processing sensory information, sending it to the cerebral cortex which then interprets that information e.g. ‘This teddy has such soft fur’

• The thalamus has many other functions:

  • Relaying information about movement

  • Playing a role in consciousness e.g. it can help to keep you alert

  • Focusing attention on what is important by filtering out irrelevant details

  • Playing a role in the regulation of emotions

• The (cerebral) cortex forms the brain’s outer layer, lying on top of the cerebrum (the largest area of the brain)

• The cortex is divided into two hemispheres: left and right

• Most brain structures are divided between the hemispheres e.g. there is a left and right thalamus and amygdala (the brain tends towards symmetry)

• The cerebral cortex has a wrinkled surface due to the number of folds it contains (which may be an indicator of advanced cognitive abilities compared to other species)

• Higher-order functions such as thinking, learning, reasoning, and problem-solving have been localised to the frontal cortex

• The visual area of the cortex - located at the back of the brain - regulates sight/vision

• The auditory area - located on both sides of the brain near the ears - regulates hearing/sound

• The motor area - located at the top of the brain and on both sides - regulates movement

• The cerebral cortex keeps developing long after birth: the prefrontal cortex is not fully developed in humans until the age of 25 years