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Experimental psychology: Better understanding of cognitive alterations in old age

Normal aging is associated with a decline in various memory abilities in many cognitive tasks. While some aged individuals fall within the normal range for adults or even develop into creative geniuses at a very late age, others present major deficits. Experimental psychology provides new insights now (published in Abstracts of the 55th Conference of Experimental Psychologists, Vienna).

Renato Frey and colleagues (Berlin) report: "Decisions from experience require exploration and learning of the available decision options. Personal factors such as age were found to shape exploration. Participants in the current study completed 84 decisions from experience on tabletcomputers in their homes, over the course of a week. Using cognitive modeling, we show that older adults perform surprisingly similar compared to younger adults. However, while younger adults tend to be risk-averse in gains, older adults tend to be more risk-averse in losses."
Stephan Getzmann and colleagues (Düsseldorf) report: "Aging usually affects the ability to focus attention on a given task and to ignore distractors." Physical training is an effective resource to decrease such age-related declines. The authors found a "positive effect of physical fitness on perceptual-cognitive processing in elderly, and on preservation of cognitive performance in aging."
Older adults experience increasing difficulty in down-regulating the activation of task-irrelevant information. Alp Aslan and colleagues (Regensburg) evaluated this inhibition-deficit hypothesis "using two tasks that have been suggested to be particularly suited to examine inhibitory control processes in episodic memory: Retrieval-induced forgetting, which reflects inhibitory control of interfering memories during selective retrieval, and directed forgetting, which reflects the (inhibitory) ability to intentionally forget ´unwanted´ memories when cued to do so. We replicated previous work by finding efficient retrieval-induced forgetting and efficient directed forgetting in ´young-old´ participants (60-75 years). Going beyond the previous work, we additionally found both forms of forgetting to decline gradually with individuals´ age and to be inefficient in ´old-old´ participants (above 75 years). These findings indicate that the retrieval-induced and the directed forgetting are ´late-declining´ capabilities, supporting the proposal of an inhibitory control deficit in (very) old age."
Lorenza Colzato (Leiden/NL) reports: "Old adults have more difficulty than young adults in stopping overt responses." One of the responsible factors is the continuous decline of stratial and extrastratial dopamine. 
"How do memory search processes change as individuals age?" Anna Sofia Morais and colleagues (Berlin) asked. "One view proposes that individuals tend to over-persist on semantic categories. An alternative view proposes that aging is associated with increased switching between categories, induced by an age-related decline in local cue-maintenance. We evaluate these hypotheses by formally modeling the memory retrieval sequences of 426 older adults in the animal fluency task (´name all the animals you can think of´), taken at multiple points during each individual´s lifetime. We modeled retrieval using a modified version of the Search of Associative Memory model applied to a semantic representation based on the Wikipedia course. Our results indicate that older adults switch between two kinds of retrieval cues - global frequency and local similarity with the previous item recalled - to traverse categories in semantic memory. Additionally, as people age, they rely more on the global frequency cue and switch more often between semantic categories. This result supports the difficulty in local cue-maintenance as a mechanism of age-related decline in memory search."
"There is perhaps no area in which the definition of ´normal´ aging is more difficult than the human nervous system. Loss of function may be due to illness or environmental factors rather than aging itself. Recent neurobiological literature suggests that more systems and functions are preserved than may be predicted from the hypothesis that aging is associated with a continuous and inevitable decline until death. Normal aging of the nervous system and of its functions may be defined as alterations with aging that occur in individuals free of clinically or neuropathologically defined diseases of the nervous system," Klaus W. Lange (Regensburg) commented.