Novelty

A recent article in the journal Neuron provides some insight into what goes on in our brains when we encounter new things. The study it reports looked at what goes on in the brain when we encounter new things. It’s true, for example, that when given a choice, people often choose something new over something they already know about. This kind of behavior seems to be mediated by neural pathways in the frontal lobes and in a deeper part of the brain called the ventral striatum. The study showed that when people made choices based on their preference for novelty, the ventral striatum showed greater activity.

What does this have to do with brain fitness? I’m interested in the study for a couple of reasons:

• First, novelty-seeking or ‘exploratory behavior’ decreases as we get older. This might even be the basis for the old saying “You can’t teach an old dog new tricks.” We know it isn’t that you can’t teach older people new things, but it may be true that older people aren’t as interested in new things.
• Second, the brain chemical dopamine is important in this neural circuit, and we know that the circuits in the brain using this chemical are less active in older people.
• Third, much of the research on improving mental abilities in older people has focused on learning new things as a key characteristic of the kind of activities that improve cognitive abilities.
• Putting these all together, it may be that choosing new things may stimulate dopaminergic activity in the ventral striatum. It is speculation, but maybe choosing novelty improves the activity of this area and the other areas linked to it. Choosing novelty may improve brain fitness.

The bottom line: This study helps us understand what goes on in the brain when we make choices based on how new something is. Its findings suggest a possible way that newness or novelty can improve brain fitness.

Reference: Wittmann BC, Daw ND, Seymour B, Dolan RJ. Striatal activity underlies novelty-based choice in humans. Neuron, 58, 967-983 (June 26th, 2008).

Psychomotor Speed

“Life goes by pretty fast. If you don’t stop and look around once in a while, you could miss it.” – Ferris Bueller in Ferris Bueller’s Day Off (1986)

One ability that is usually measured in studies of cognitive aging is “psychomotor speed.” It’s often considered as a separate ability and has been shown to decline with increasing age. What is it, and why is it important?

Psychomotor speed means being able to coordinate thinking fast with doing something fast. Driving a car is an obvious example. You have to move your eyes and your head to know what’s going on around you. You have to think about what your car is doing, and what other drivers, pedestrians, and animals are going to do. And you have to respond to what you see by doing something such as pressing the brake or accelerator pedals, turning the steering wheel, or using the turn signal. The “psycho” in psychomotor refers to the thinking part of this skill, while the “motor” part refers to doing something with your muscles, like hitting the break when you see a ball bouncing into the street. When you’re younger, you’re generally able to do this sort of thing much more quickly than you can as you get older. Some studies show that psychomotor speed starts declining in someone’s 20s, and continues to decline with age.

Like Ferris Bueller says, “life goes by pretty fast.” A lot of things go by pretty fast, and declines in psychomotor speed affect more than just driving ability. Another example that isn’t quite as obvious is your ability to understand conversations. You may not think about it this way, but understanding what people are saying requires that you take in all sorts of sounds, sort out what’s meaningful from what’s noise, and then figure out what a speaker is saying based on this complex of sound and meaning. And you have to do all of this pretty quickly, before the next volley of sound comes at you. Some people believe that this is one of the issues that causes older people to say they have trouble understanding conversation. It’s not just having problems in hearing (that can often be helped with a hearing aid) but also with speed of processing or psychomotor speed.

Since psychomotor speed is something that can be improved with training, it may be possible for older people to improve it in ways that might help in everyday life. Both auditory (hearing) and visual speed training are included in many computer brain training programs.