Researchers investigated the impact of prenatal exposure to the organophosphate pesticide chlorpyrifos on hippocampal development and spatial memory in rodent offspring. Pregnant Sprague-Dawley rats were fed daily doses of chlorpyrifos (5 mg/kg of body weight) mixed into their food throughout their entire 21-day gestation period. The control group of pregnant rats was fed identical food without the pesticide under the same laboratory conditions.
At 30 days of age, the offspring underwent cognitive assessment using the Morris water maze task to measure spatial navigation and memory retention. Following behavioral testing, the offspring were euthanised, and their brains were analysed. The pesticide-exposed offspring exhibited a 35% reduction in brain-derived neurotrophic factor (BDNF) levels in the hippocampus and took significantly longer to locate the hidden platform during reversal trials compared to the control group. There were no observable differences in physical growth or motor function between the two groups.
Justify whether the use of non-human animals in this study was appropriate.
Practise Edexcel A Level Psychology Issues and debates with exam-style questions for A Level Psychology. 147 questions covering Issues and debates, matched to the Edexcel A Level Psychology (9PS0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
