The cognitive or brain reserve hypothesis states that it is possible to build up the brain’s resilience to neuronal damage and delay the onset of Alzheimer’s symptoms. The concept of brain reserve stems from the repeated observation that the relationship between clinical symptoms and actual brain pathology is not direct. For example, Katzman and colleagues (1989) described 10 cases of cognitively normal older adults who, at death, were discovered to have advanced Alzheimer’s disease pathology in their brains. The researchers hypothesized that these individuals did not show symptoms of Alzheimer’s because they had larger brains, that is more neurons. The idea is that having a larger reserve of neurons and abilities can offset the losses caused by Alzheimer’s. The concept of cognitive/brain reserve is thus defined as the ability of an individual to tolerate progressive brain pathology (including Alzheimer’s plaques and tangles) without demonstrating clinical cognitive symptoms.
Subsequent research has shown that frequent participation in mentally stimulating activities reduces the risk of Alzheimer’s disease, possibly by increasing brain reserve. As a consequence, brain activity or exercise in general is hypothesized to help increase brain reserve.
In our view, brain training is more than the stimulation triggered by challenging daily activities. We define brain training as the structured use of cognitive exercises aimed at improving specific brain functions (see Chapter 3).
Rigorous and targeted brain training has been used in clinical practice for many years as a way of helping patients recovering from the effects of traumatic brain injury, stroke, and other neurological disorders. It can help improve memory, attention, confidence and competence, reasoning skills, and even reduce anxiety.
Past research outside the clinical domain has shown that cognitive abilities can also be trained systematically in healthy individuals. Individuals trained in a specific task usually will become better at this task (see for instance Willis et al., 2006 or Ball et al., 2002). What is even more important, such training sometimes has generalized effects improving performance on other, similar tasks.
Although it has been long thought that “you cannot teach old dogs new tricks, many studies show that cognition can be trained at all ages. In particular, many studies have shown that middle age individuals as well as older individuals can learn techniques to boost their memory (see for example Brooks et al., 1999; Derwinger et al., 2003 or the meta-analysis published by Verhaeghen et al. in 1992).
If we could summarize a variety of research fields and findings into a few useful guidelines, we would say that ¨good¨ brain exercise requires variety, challenge and novelty. Read the guidelines below.
Varied, novel and challenging exercises will necessarily induce learning. Learning is critical. When one learns a new fact or a new way of accomplishing a task, neurons and synapses “ connections “ in the brain change. This is neuroplasticity as defined early. The changes associated with learning may help increase one’s brain reserve, contributing to general brain health.
Learning and changing is never easy. This requires effort. As Dr. James Zull points out learning and changing require getting out of our comfort zones. Often, the fear of failing is a key obstacle to learning.
Recipe for a good mental exercise
- Variety: Excessive specialization is not the best strategy for long-term brain health. A better strategy is to stimulate the multiple functions of the brain. This can be done by creating a mental workout circuit similar to a physical exercise circuit in a health club since our brains are composed of multiple structures with multiple functions.
- Challenge: The goal is to be exposed to increasing levels of challenge, so that a task never becomes too easy or routine.
- Novelty: Trying new things is important since very important parts of the brain, such as the prefrontal cortex, are mostly exercised when we learn to master new cognitive challenges.
These are the recipe for a good mental exercise
Keep learning by reading more articles in the Resources section, and also please consider joining our free monthly Brain Fitness eNewsletter
This new online resource is based on the content from the book The SharpBrains Guide to Brain Fitness (May 2009, $19.95), by Alvaro Fernandez and Dr. Elkhonon Goldberg.