Contrary to this idea, previous research has not supported a link between intellectual enrichment and cerebral efficiency in healthy persons.
Despite presumably high statistical power and methods very similar to our own, these studies did not show an association between intellectual enrichment and cerebral efficiency in healthy individuals.
The unique relationship between intellectual enrichment and cerebral efficiency in neurologic patients is consistent with the cognitive reserve hypothesis, which does not posit that enrichment leads to gains in neurocognitive functioning per se; rather, enrichment protects against neurocognitive decline secondarily to disease.
The cognitive reserve hypothesis posits that intellectual enrichment is associated with cerebral efficiency (Stern et al., 2002, 2005).
The current research utilized fMRI to demonstrate that intellectual enrichment is associated with cerebral efficiency in neurological patients, thereby supporting the cognitive reserve hypothesis.
To explain these findings, Stern posited that intellectual enrichment is associated with cerebral efficiency, which provides a 'cognitive reserve' against disease-related cognitive impairment (Stern et al., 2002, 2005).
An alternative hypothesis is that vocabulary knowledge may simply be a proxy of a more genetically-based intellectual capacity, and that greater cerebral efficiency from a young age may help people complete more school and learn more information.
If intellectual enrichment is equally related to cerebral efficiency in healthy persons as in neurological patients, then patients with higher intellectual enrichment are simply less likely to cross the threshold of cognitive impairment because their cerebral functioning was more efficient at the outset.
What is it about intellectual enrichment that leads to greater cerebral efficiency?
Within this context, it makes sense that intellectual enrichment is more related to cerebral efficiency in neurological patients (i.e. multiple sclerosis) than in healthy people.
