Biological language acquisition and the critical period
Connect language centres and Chomsky’s account to critical-period evidence from Senghas, while recognising social and cultural influence.
Section Paper 2 · Paper 2 · Topics 4–6 and non-experimental methods
Original teaching mapped to Cambridge IGCSE Psychology 0266 Version 3 for 2027–2029. The course is independent study support, not Cambridge material, an official mark scheme or an awarded grade. Named-study notes summarise the required findings; candidates are not expected to evaluate named studies. Self-check practice is not official grading, a timed Paper 1/2 simulator or teacher review.
Before you begin
- Use the Version 3 syllabus and confirm availability in your administrative zone with Cambridge and your school. Both papers are compulsory. The updated named-study summaries are required context; full original research articles are not required.
Work on paper. Try each question before revealing help, and explain why your method works.
Quick readiness check
Before biological language acquisition and the critical period, which approach is most useful?
What you will learn
- Locate Broca’s and Wernicke’s areas and distinguish their functions
- Explain LAD, universal grammar and the critical period
- Distinguish Broca’s and Wernicke’s aphasia
- Use Senghas and a social/cultural counterargument
Language uses specialised brain areas
Broca’s area in the frontal lobe is associated with speech production; Wernicke’s area in the temporal lobe with understanding speech. Aphasia is language impairment following brain damage. Broca’s aphasia primarily affects fluent production, whereas Wernicke’s aphasia primarily affects understanding and meaningful speech.
Chomsky proposes a biological readiness for language
The language acquisition device (LAD) is a proposed inborn capacity for acquiring language; universal grammar is the idea that languages share underlying structure. A critical period is an early developmental window when a person is especially ready to acquire a particular skill.
Named study: Senghas
Twenty-five deaf sign-language users in Nicaragua watched a short cartoon and retold it in sign. Those who began learning from birth used more verb inflections and grammatical agreement than those who began later. This supports a critical-period account. Sign languages are full linguistic systems; social interaction and cultural environment also shape language, so biology is not the only influence.
Pause and explain
Which response best shows understanding of biological language acquisition and the critical period?
Worked example
A person speaks fluently but struggles to understand spoken sentences after brain damage. Which language area is most relevant?
Show the worked solution
- The difficulty is comprehension rather than speech production.
- Wernicke’s area is linked with understanding speech.
- The scenario is more consistent with Wernicke’s aphasia.
Answer Wernicke’s area and Wernicke’s aphasia are most relevant to impaired speech comprehension.
Try a topic test
Choose Easy, Normal or Difficult. Save your answers and open worked review after finishing.
Test this topic →From guided practice to a new situation
Write your answer and reasoning first. Use a hint only if you are stuck. The model solution is for self-checking; your written work is not automatically marked.
A learner struggles mainly to understand speech after brain damage. Match the likely area and aphasia label.
Give me a hint
Focus on comprehension.
Compare my reasoning
- Understanding speech is associated with Wernicke’s area.
- Damage can cause Wernicke’s aphasia.
- This is distinct from the production difficulties linked to Broca’s area.
Wernicke’s area; Wernicke’s aphasia.
Look for these in your work
- Matches comprehension
- Names the aphasia
- Contrasts production
What pattern in Senghas supports a critical period for language acquisition?
Give me a hint
Compare participants who began at different ages.
Compare my reasoning
- Participants who learned sign from birth were compared with later learners.
- Earlier learners used more verb inflections and grammatical agreement.
- This supports an early window for developing complex language.
Earlier sign-language learners used more complex verb features, supporting the critical-period explanation.
Look for these in your work
- Names the comparison
- States the result
- Links it to the theory
A child develops language through frequent conversation with family. Which limitation does this illustrate for a purely biological account?
Give me a hint
Identify the environmental contribution.
Compare my reasoning
- The child receives social interaction.
- The family provides language experiences and feedback.
- This shows that social and cultural factors also influence acquisition.
The case supports a social/cultural contribution alongside biological readiness.
Look for these in your work
- Identifies interaction
- Explains the environment
- Avoids an either/or conclusion
Common mistakes
- Swapping Broca’s and Wernicke’s functions.
- Treating sign language as less complete than spoken language.
- Claiming Senghas proves biology is the only influence.
What can you explain now?
Which area is linked to speech production?
Compare with the explanation
Broca’s area
Broca’s area is in the frontal lobe and linked to production.
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Make it stick
How do specialised language areas and Chomsky’s proposal connect with critical-period evidence and social experience?
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