clair073

In most people, their brains get smaller as they age. It is not so much that neurons die but that their terminals and synaptic junctions shrivel. A known cause is the over-secretion of cortisol by stress, but perhaps there are also other age-related causes. However, shrinkage with age is not inevitable. Certain people are "super-agers," defined as adults over 80 with memory at least as good as normal middle-aged adults. A usually reliable index for decline in memory ability is the degree of brain shrinkage, specifically cortical volume. Brain-scan studies show that super-agers have thicker layers of cortex than do others of the same age. Thus, their cortex has not shrunk as much as average elderly or they had more to start with. It is possible that something about the lifestyle of super-agers protected them from brain atrophy. It is not convenient to know how much cortical volume the elderly had in their youth. But the second option has been tested in a study that compared th...

No one is born honorable. If you doubt me, just watch little kids at play. Scholarly research has confirms the point. Michael Lewis, a prominent psychologist at Rutgers, has conducted many studies of how children naturally lie and deceive and are even encouraged to do so by well-meaning parents. Certain ways of expressing emotion are taught to be acceptable while others are not. One experiment, for example, showed that children are usually taught to express sadness when their mother leaves them with a baby sitter. But the reality was that children were not sad and recovered quickly when the mother left. Other examples are how children are taught to express responses to minor insults or injuries. Some kids are taught that it is alright to over-react. Lewis and his colleagues conducted some classical experiments in young children that revealed how their tendency for false behavior changed with age. They secretly videotaped children in an honesty test in which they were told not to peek a...