Ethical considerations

Protection from harm

ensuring that participants are not exposed to physical or psychological distress during a study.

Maguire et al 2000

To investigate the effect of spatial navigation on size of hippocampus using MRI

Participants: 16 right-handed male London taxi drivers and 50 right handed male non-taxi drivers (control group)
Methods:
Taxi Drivers had completed the "Knowledge" test and held their licenses for at least 1.5 years.
placed in MRI and compared
Voxel-Based Morphometry (VBM) measured the density of grey matter in the brain.
Pixel Counting calculated the hippocampal area in MRI images.

Taxi drivers had larger posterior hippocampi and smaller anterior hippocampi compared to controls.
This suggests that the hippocampus adapts to environment
posterior hippocampus involved in using previously learned spatial information
the anterior hippocampus linked to learning new spatial layouts.

MRI is a non-invasive technique, participants had to lie still inside a confined scanner, which can cause discomfort or feelings of claustrophobia in some individuals.
researchers had an ethical responsibility to ensure that participants were screened for medical issues (such as metal implants) and were not exposed to unnecessary psychological stress. Participants would also have been informed about the procedure in advance, allowing them to give informed consent.

This shows that even non-invasive brain imaging studies must consider participant wellbeing, especially when studying brain–behaviour relationships using techniques such as MRI.