Maybe it’’s a sign of a mature mind when some of life’’s bigger questions-about love, faith, ambition-suddenly seem more manageable than smaller ones, such as:Why did I just open the refrigerator Where on earth did I put my keys Where did I write down that phone number
Our capacity for storing and recalling information does not stream down like sand through an hourglass, as neurologists once believed. On the contrary, new research suggests that, when stimulated in the right way, brains of almost any age can give birth to cells and forge fresh pathways to file away new information. This emerging picture has not only encouraged those who treat and care for the 5% of older adults who have dementia (痴呆症) such as Alzheimer’’s disease, but also generated a wave of optimism among those studying memory changes in the other 95%, as well as an increasing public fascination with "memory enhancement" dietary supplements, books and brain-improving techniques.
The slight failures of memory that many of us attribute to a failing brain are often due to something entirely different: anxiety, sleep problems, depression, even heart disease. The biological nuts and bolts of learning and memory in fact change little over time in healthy people, researchers say. "There’’s very little cell loss, and structurally all the machinery is there, even very late in life," said a neuroscientist Greg Cole. It’’s the cells’’ speed and ability to send and receive signals that diminish gradually, which is what makes the mind go blank when trying to recall familiar words and names.
For more than a decade, researchers have known that people who have active, intellectually challenging lives are less likely to develop dementia than those who do not. Part of this difference is attributable to intelligence, some doctors believe:The more you start with, the longer it takes to lose it. And new evidence suggests that the act of using your brain is in itself protective, no matter who you are.
All of the activities, such as reading newspapers, watching TV, playing games, etc. canimprove people’’s scores on standard tests measuring recall of numbers and names, experts say. They also acknowledge, however, that there is a big difference between playing chess with a friend and doing a mental exercise, such as memorizing numbers. One is an organic part of a person’’s life, the other a purely intellectual exercise, done in isolation. The first is fun; the second, often, is a tiring task.
The phrase "nuts and bolts" in Par. 3 most probably means