Specific types of sensory stimuli and activities, especially those that involve non-routine actions and thoughts, produce more of the chemicals that encourage growth of new dendrites and neurons in the brain. Routine activities become so automatic that they are done largely unconsciously (ever get up in the morning and walk to the kitchen before you are really conscious?). This means they require less activity in the brain, and exercise it less.

Therefore, a neurobic activity should do one or more of the following:

1. Involve one or more senses in a new context.

2. Involve your full attention.

3. Break your routine in a significant way.

Neurobics do not have to be complicated. They also don't require that you set aside special times for them. As long as they follow the guidelines above, many simple activities make for good brain exercises, and can be worked into your normal day.

Some Brain Exercises or Neurobics

Learn braille. This is a tough one, but learning to read with your fingers definitely involves one of your senses in a new context.

Do something in a new environment. Go to a new park, or a new store. Travel, by the way, seems to slow age-related mental decline.

Leave the lights off. Get around your home by memory and feel. This certainly fully engages your attention, but be careful of course.

New odors in the morning. Have new odors, like a bottle of mint extract ready to smell first thing in the morning, to "wake up" your brain.

Shower with your eyes closed. Your other senses become more active when you cannot see, and a shower engages several senses.

Brush your teeth with your non-dominant hand. This is difficult for some of us, and requires full attention the first time you try it.

Wear different clothes. Ever notice how you feel differently when you wear different clothes. You may think differently as well. Give it a try.

Choose to respond differently. Catch yourself in a normal and mostly unconscious response to a situation, and choose to respond in a different (preferably better) way.

Take a new route to work. It doesn't have to be a longer route - just different. You may even find a faster way to work once you break your routine.

Act confident. In a situation you are unsure about, choose to act confidently. You'll notice that your mind gets very active once you adopt the assumption that you will know what to do.

Learn to distinguish coins using only your sense of touch. This brain exercise can be a way to kill time when waiting for an appointment. If you really want a challenge, see if you can distinguish paper currency denominations by touch.

Of course following the simple guidelines above (involve your full attention, use one or more of your senses in a new context, or break your routine in a significant way) you can invent your own neurobics routine. Have some fun with these brain exercises.