Researchers used MRI scans to measure hippocampal volume in two groups of adults. Everyone in the clinical depression group had taken medication for several years. The comparison group did not have clinical depression and had not taken medication.
| Group | Mean hippocampal volume (cm³) |
|---|---|
| Clinical depression | 3.1 |
| Comparison | 3.4 |
Explain two weaknesses of concluding from these findings that clinical depression causes a smaller hippocampus.
38 exam-style questions on OCR GCSE Psychology 3.3 Application: The development of treatments, covering 3.3.1 Anti-psychotics and anti-depressants, 3.3.2 Psychotherapy, and 3.3.3 Neuropsychology for study. Each one has a worked solution and a mark scheme showing where the marks go.