One common denominator of the entire list of factors mentioned so far is cognitive effort. In other words, for some activity to be useful in maintaining or enhancing cognitive vitality, it has to require some effort. This is not unlike physical exercise whose effectiveness calls for at least some minimal investment in physical effort. Engaging exclusively in very easy exercises would have only a marginal impact on one’s physical fitness. By effort, we imply the need to actively focus on the task at hand and allocate sufficient resources of attention to carry it to its successful completion.
A wonderful illustration of the benefits of cognitive effort is provided by the famous “Nun Study” by Snowdon. As part of an attempt to study the antecedents of cognitive health in elderly nuns, the study analysed one page autobiographical essays written by them at the average age of twenty-two when they were in college. These short descriptions were analysed blindly by linguistic experts for “idea density” [i.e., the number of different ideas per every ten words] and “grammatical complexity” [simple versus complex sentence construction, branching, etc]
To everybody’s astonishment, the results were able to predict cognitive health sixty years later, at the average age of eighty. Sisters with higher density in college had significantly higher scores on standard cognitive tests, and were les likely to have Alzheimer’s disease than those with lower idea density. A similar relationship, although weaker, was found between grammatical complexity and cognitive scores..
Both high idea density and grammatical complexity require greater effort on the part of the writer [and for that matter the reader as well]. The ability and willingness to invest in such cognitive effort bode well for the future vitality of the sisters.
The opposite of cognitive effort is automatic processing. Cognitive activity that can be carried out automatically does not require any effort at all. As certain activities become gradually more familiar with experience, they become easier and less effortful. At some point in time they might become fully automatic, thus releasing us from the need to attend to them altogether.
The brain’s capacity for developing automatic sequences of routine tasks is on the whole a major blessing. The number and variety of activities that we are able to carry out without attending to the process itself is impressive indeed. Consider the way we walk home from the station without having to rehearse the directions. In fact, we may be deep in thought about other matters and yet we find ourselves entering our home. Think about the complex eye-hand coordination necessary fro a smooth handshake. We just do it; there is no need to think about it anymore. Reading itself becomes an automatic activity through experience.
Thus, visual pattern of whole words is stored in memory and the jump from looking at a page and extracting the meaning becomes effortless. In the same way, with years of experience, some elements of driving become automatic as well, freeing the driver to talk, listen to music, or otherwise engage part of his/her attention. Automatic processing, however, is not without its costs. The convenience of well-rehearsed actions, allowing the brain to manage without cognitive effort, encourages certain forms of mental laziness to take root. The outcome of such idleness, just like in the case of physical idleness, is getting out of shape and losing some cognitive vitality. Consequently, one of the best ways to build cognitive reserves is to engage in activities that are relatively new, and preclude automatic processing.
When on a trip to a new place, the road back to the hotel cannot be taken without proper attention allocation on our part. We must be well aware of the surrounding circumstances, remember a few key reference points and plan the route accordingly. In the same manner when driving a new car in a new location, the driving would involve much more deliberate attention than typically. Novelty, the natural opposite of routine, poses important challenges to the brain, and contributes to cognitive wellbeing.
Our brains are well suited to profit from experience, and very few things retain their novelty for a long time. On the contrary, we are capable of developing routines extremely fast. This gives us the good feeling of mastering a news situation. Even the most complex activities have significant components that are routine. The cognition-enhancing qualities of novelty must therefore be actively pursued, and we cannot rely on opportunities provided by everyday life experience to do the trick for us. This is further augmented by the natural preference of the human brain to develop routine procedures that save energy and effort.
There are two very different modes of action our brains can take when faced with a particular cognitive challenge. The first one, involving situational analysis, and choice between alternatives, is clearly effortful. The second, on the other hand, relies entirely on prior experience. Our mental database is searched for similar instances in the past, and the precedents serve as the basis for the current solution.. This is much less effortful, and most of the process can be carried out automatically without our awareness. As we grow older and more experienced, this second mode takes over a growingly larger segment of our personal decisions. The opportunities for effortful cognitive processing would be fewer, and its beneficial contribution to cognitive vitality would be greatly reduced.
We cannot, therefore, rely on everyday life to provide sufficient opportunities for exercising our brains. In the same manner, the sedentary lifestyle of most modern people does not provide sufficient physical exercise. Consequently, just as we need to seek specific ways to “work-out” physically, we have to seek ways to exercise our brains.