Three brain regions, each with a job
The brain starts as a hollow neural tube; within five weeks its front swells into three regions. The forebrain (largest) handles thinking, memory, language and emotion, and develops last. The midbrain (smallest) sits between the other two, relaying signals and supporting alertness. The hindbrain, at the base and back, holds the cerebellum and medulla and runs the functions that keep the body alive.
Cerebellum: balance and coordination
Cerebellum — a hindbrain structure controlling balance, posture and the coordination of voluntary movement, making practised actions smooth and automatic: walking without falling, writing, pouring, cycling. It develops rapidly in the first year and through childhood, so coordination arrives gradually. Damage leaves movement clumsy, unsteady and badly timed — so "they cannot move" is wrong; the point is movement no longer smooth.
Medulla: involuntary functions
Medulla — at the base of the hindbrain. It controls involuntary functions: breathing, heart rate, blood pressure, and reflexes such as swallowing and coughing. Because these must work from birth, it develops among the earliest structures, before the forebrain matures — link that order to the function, not just the list. The consequence, worth a second mark: damage is life-threatening, as these functions cannot be done consciously.
Drawn from real examiner reports.
The brain is finished at birth
A newborn's brain is not complete; development is uneven and sequenced. The medulla is functional earliest (breathing from birth); the cerebellum develops through childhood, so balance arrives gradually; the forebrain finishes last, so reasoning keeps improving. Biologically driven but shaped by experience — evidence in a nature-nurture answer.
Two marks, but the same point twice
Asked to describe the medulla, candidates write "controls involuntary actions", then "does things you do not think about" — one point reworded, so a 2-mark describe scores 1. The two points must differ: a named function (breathing) plus a second function (swallowing) or a consequence (damage is life-threatening).
A single point on the cerebellum was commonly reached but a second rarely (Nov 2020 P1 Q2), and the same on the medulla — "involuntary actions" reached, a second point rarely (June 2023 P1 Q1b). A 2-mark describe needs two unique points (June 2023 P2 Q22).
Cerebellum ≠ cerebrum; medulla ≠ midbrain
Similar names swap easily; a swap scores zero. The cerebellum (hindbrain) controls balance and coordination; the cerebrum is the forebrain area for thinking, memory and language. The medulla (hindbrain base) runs involuntary functions like breathing; the midbrain sits between them, relaying signals. Learn each as name + region + function.
Answers describing the wrong structure score zero even when the psychology is sound — examiners report the equivalent on Piaget's stages, where candidates defined a different stage from the one asked (June 2024 P1 Q1a and Q1b) and answered on post-conventional morality when conventional was asked (June 2023 P1 Q3).
Difference needs a connective word
Asked for the difference between two structures, many write two correct definitions side by side and stop — the difference is only implied, worth one mark. The second mark needs a connective (whereas, while) naming the axis they differ on: "the cerebellum controls voluntary movement, whereas the medulla controls involuntary functions."
"Describe the difference" items are routinely answered with two separate definitions, treated as an implicit difference worth one mark; connectives such as "whereas" earn the second (June 2019 P1 Q6; June 2022 P1 Q7 and Q22).
State a feature, do not define it
A "state one feature" or "name one function" item wants a single fact, not a definition of the whole structure. Asked for a feature of the hindbrain, "a region at the back" defines the term and misses the mark; the feature is what it does — "it holds the cerebellum, which controls balance". State/name wants one specific thing: give the function, not a definition.
Examiners report "state one feature" answered by defining the term instead (June 2023 P1 Q6).
Location is not a function
Naming where a structure sits earns nothing. "The forebrain is at the front" or "the cerebellum is at the back" are locations, and the scheme credits function. Say what it does: the forebrain handles thinking and memory, the medulla runs breathing and heart rate, the cerebellum coordinates movement. Use location only to identify a structure, then go to its job.
Naming a weakness without justifying it
On strength/weakness or improvement items, candidates name a point and stop — "just one person", "add more people" — without saying how it weakens or improves the evidence. Identification alone caps the mark. Justify it: "the evidence is from one injured individual, so the finding may not generalise to everyone." Pair the point with its reasoned consequence.
Identification without justification on strength/weakness and improvement items loses marks across the Paper 1 reports (June 2024 P1 Q11b and Q15b).
Match the answer to the command word
Each command word wants a different shape: state = one specific fact; describe = two distinct points; explain = a reason or link; assess = both sides plus a conclusion. Do not describe when asked to explain, or define when asked to state.
Apply first — AO3 needs AO2
The scenario is the only source of AO2 (application) marks. Naming the person or repeating the stem does not count; tie the behaviour described to a named structure. And AO3 cannot be given without AO2 present — a generic answer scores zero. Apply first, then evaluate.
The 9-mark Assess: balance and a conclusion
A 9-mark Assess is AO1 3 / AO2 3 / AO3 3; the top band is lost through missing AO3 and balance. Define each structure, link it to the scenario, argue both sides — generalisability, objectivity, validity — then conclude. Continuous prose; no bullet points.
2-mark explain = knowledge + link
A short 'explain' worth two marks usually splits 1 AO1 + 1 AO2: one knowledge point plus one scenario link. Say what the structure does ("the cerebellum coordinates movement"), then link it to the behaviour ("so the cycling smooths out"). No link means one mark at most.
Neural tube — the hollow structure formed in the first weeks after conception from which the whole brain and spinal cord develop.
Forebrain — the largest of the three brain regions, responsible for thinking, memory, language, emotion and processing information from the senses.
Midbrain — the smallest region, lying between the forebrain and the hindbrain, which relays signals between them and is involved in vision and hearing reflexes, movement and alertness.
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