In one line: Your brain and body never stop changing, from before birth to old age.
Biological change is happening in you right now. Reading this sentence is slightly reshaping the connections in your brain.
Psychology often asks how and why behaviour changes. Changes in the brain and body are one big reason.
Remember: A brain is a builder, not a statue.
It keeps rebuilding itself with age and experience.
Free preview
This is the free notes preview
You're reading the free notes. Aimnova Pro unlocks the full study experience — and you can try it with your first topic free to keep:
- FlashcardsLock in vocabulary and key terms with spaced repetition.
- Practice questionsAnswer exam-style questions and get instant AI marking.
- Mock exams & past-paper vaultSit full mocks and see exactly how examiners award marks.
- Personalised study planA daily plan built around your exam date and weak areas.
Key idea: Biological change has four main sources. Some follow a timetable we are born with. Some depend on what happens to us.
Sources of biological change
Maturation
The brain develops on a rough timetable (maturation).
The part used for planning and self-control keeps developing into the mid-twenties.
Neuroplasticity
Experience reshapes the brain's connections (neuroplasticity).
Practise a skill, and the pathways it uses get stronger.
Hormones
Chemical messengers in the blood drive change.
The rise in hormones at puberty reshapes body, brain and mood.
Recovery after injury
After damage, healthy areas of the brain can slowly take over some of the lost functions.
Maturation · Plasticity · Hormones · Recovery
Take a teenager learning to drive. Maturation gives steadier judgement over the years. Neuroplasticity turns clumsy first attempts into smooth habits. Several biological changes work together.
Exam tip: "The brain changes" is too vague.
Name the source of the change, and link it to the behaviour.
Memorize terms 3x faster
Smart flashcards show you cards right before you forget them. Perfect for definitions and key concepts.
Key idea: Some biological change takes years. Some happens almost overnight.
Gradual change
- Builds up slowly
- The brain maturing through the teenage years
- A skill improving with daily practice
Sudden change
- Happens quickly
- A head injury that changes someone's personality
- A swing in mood as hormone levels shift
Change also differs in whether anyone meant it to happen.
Puberty is expected: it follows the body's timetable. An illness or an injury is unplanned. And some change is brought about on purpose, as when someone trains every day or takes a medicine.
Use it in an answer: Say what kind of change a study or an example shows: gradual or sudden, planned or unplanned.
Key idea: Biology shapes behaviour. It does not fix it for good.
One view says that behaviour is decided by our genes, our brain and our hormones, so we have no real choice. This is biological determinism.
What supports it
- The brain matures on a timetable nobody chooses
- A brain injury can change how a person behaves
- Hormones shift mood without asking
What limits it
- The brain changes with what we do
- The same biology leads to different lives in different surroundings
- People make choices and act on them
The second column matters most. Because of neuroplasticity, the brain is changed by behaviour as well as changing it. A teenager's brain makes risky driving more likely. Practice, rules and her own choices still decide what kind of driver she becomes.
Remember: Biology sets the starting point and the limits. It does not write the whole story.
Know your predicted grade
Take timed mock exams and get detailed feedback on every answer. See exactly where you're losing marks.
How this is asked: Change is one of the concepts for the 15-mark essay on Paper 1. The essay is set in a context, such as human development.
You do not need the details of studies. You need clear ideas, explained examples and a judgement.
The essay pattern
- Say what kind of change the question is about.
- Explain one biological source of change and link it to a behaviour.
- Explain a second source, with its own example.
- Give the other side: what biology cannot explain alone.
- Finish with a judgement.
The trap: a list of brain facts: Facts about the brain are not yet an answer about change.
For each one, say what changes in behaviour, and when.
In the context of human development, discuss how biological change contributes to changes in behaviour as children grow into adults.
Model answer plan
See the answer broken into clear points, with guidance on how each point earns marks.