Neuroplasticity is the brain’s ability to change its structure and function in response to experience, learning, environmental demands, or injury. It demonstrates that the brain is adaptable rather than permanently fixed after childhood.
Within the IB Psychology biological approach, neuroplasticity explains how behaviour and the environment can influence the brain. Repeated experience activates particular neurons together, strengthening or reorganizing the connections within neural networks.
| Mechanism | How the brain changes |
|---|---|
| Synaptic plasticity | Frequently used synaptic connections become stronger, while less-used connections may weaken. |
| Neural pruning | Unnecessary or weak neural connections are removed, making frequently used networks more efficient. |
| Structural change | Experience may alter grey-matter volume or the organization of brain regions. |
| Functional reorganization | Following injury, healthy brain regions may partly take over functions previously performed by damaged areas. |
A key supporting study is Maguire et al. (2000). The researchers used MRI scans to compare 16 male London taxi drivers with a matched control group. Taxi drivers had greater grey-matter volume in the posterior hippocampus, a region associated with spatial memory, and time spent as a taxi driver was positively correlated with posterior hippocampal volume.
These findings suggest that repeatedly navigating London’s complex street system was associated with structural brain adaptation. However, this was correlational research, so it cannot establish that driving caused the differences. Pre-existing hippocampal differences may have helped some participants become taxi drivers. The small, all-male sample also limits generalizability, while brain-scan data require informed consent and protection of participants’ medical privacy.
A common misconception is that neuroplasticity means any brain region can perform any function. Plasticity has biological limits: functions are supported by specialized, interconnected networks, and recovery after damage is often incomplete.
Exam technique: For an SAQ, define neuroplasticity, explain the mechanism, accurately describe one study, and explicitly link its findings to brain change. In an essay, evaluate causality, sampling, brain-imaging methods, ethics, and the interaction between biology and environmental experience.