Discuss changes in information processing speed that individuals experience in the aging process. Compare and contrast the neural network view with the information-loss view

Question

What will be an ideal response?

Answer 1

As processing speed slows, certain basic aspects of executive function, including attention and working memory, decline. On both simple reaction-time tasks and complex ones, response time increases steadily from the early twenties into the nineties. The more complex the situation, the more disadvantaged older adults are. Although the decline in speed is gradual and quite small—less than 1 second in most studies—it is nevertheless of practical significance. Researchers agree that changes in the brain are responsible but disagree on the precise explanation. According to the neural network view, as neurons in the brain die, breaks in neural networks occur. The brain adapts by forming bypasses—new synaptic connections that go around the breaks but are less efficient. Another hypothesis, the information-loss view, suggests that older adults experience greater loss of information as it moves through the cognitive system. As a result, the whole system must slow down to inspect and interpret the information. With each step of thinking, information degrades. The older the adult, the more exaggerated this effect. Complex tasks, which have more processing steps, are more affected by information loss. At present, researchers are not sure whether just one or two neural changes, or multiple neural changes that vary across individuals, underlie declines in processing speed. What is clear is that processing speed predicts adults' performance on many tests of complex abilities. The slower their reaction time, the lower people's scores on tests of memory, reasoning, and problem solving, with relationships greater for fluid- than crystallized-ability items. This suggests that processing speed contributes broadly to declines in cognitive functioning. Yet processing speed correlates only moderately with older adults' performances, including fluid-ability tasks. And it is not the only major predictor of age-related cognitive changes.