thinker_jeff Posted April 18, 2011 Posted April 18, 2011 ScienceDaily (Apr. 12, 2011) — Scientists at the University of California, San Francisco have pinpointed a reason older adults have a harder time multitasking than younger adults: they have more difficulty switching between tasks at the level of brain networks. Juggling multiple tasks requires short-term, or "working," memory -- the capacity to hold and manipulate information in the mind for a period of time. Working memory is the basis of all mental operations, from learning a friend's telephone number, and then entering it into a smart phone, to following the train of a conversation, to conducting complex tasks such as reasoning, comprehension and learning. "Our findings suggest that the negative impact of multitasking on working memory is not necessarily a memory problem, per se, but the result of an interaction between attention and memory," said the senior author of the study, Adam Gazzaley, MD, PhD, UCSF associate professor of neurology, physiology and psychiatry and director of the UCSF Neuroscience Imaging Center. The finding, reported in the online early edition of Proceedings of the National Academy of Sciences (week of April 11, 2011), complements findings by the Gazzaley lab focused not on interruptions, or multitasking, but on distractions. This research showed that the brain's capacity to ignore distractions, or irrelevant information, diminishes with age and that this, too, impacts working memory. Researchers know that multitasking negatively impacts working memory in both young and older adults. However, anecdotal accounts of "senior moments" -- such as forgetting what one wanted to retrieve from the refrigerator after leaving the couch -- combined with scientific studies conducted at UCSF and elsewhere indicate that the impact is greater in older people. In the current study, scientists compared the working memory of healthy young men and women (mean age 24.5) and older men and women (mean age 69.1) in a visual memory test involving multitasking. Using functional magnetic resonance imaging, the researchers tracked blood flow in the participants' brains to identify the activity of neural circuits and networks. Participants were asked to view a natural scene and maintain it in mind for 14.4 seconds. Then, in the middle of the maintenance period, an interruption occurred: an image of a face popped up and participants were asked to determine its sex and age. They were then asked to recall the original scene. As expected, older people had more difficulty maintaining the memory of the original image. The fMRI analysis revealed why. When the young and older adults were interrupted, their brains disengaged from a memory maintenance network and reallocated neural resources toward processing the interruption. However, the younger adults re-established connection with the memory maintenance network following the interruption and disengaged from the interrupting image. The older adults, on the other hand, failed both to disengage from the interruption and to reestablish the neural network associated with the disrupted memory. "These results indicate that deficits in switching between functional brain networks underlie the impact of multitasking on working memory in older adults," said lead author Wesley C. Clapp, PhD, a postdoctoral fellow in the Gazzaley lab. The lab's parallel research on the impact of distractions on working memory broadens the perspective of what happens in the aging brain. The ability to ignore irrelevant information -- such as most of the faces in a crowded room when looking for a long-lost friend -- and to enhance pertinent information such as the face of a new acquaintance met during the search for the old friend -- is key to memory formation. "The impact of distractions and interruptions reveals the fragility of working memory," said Gazzaley, who also is a member of the W. M. Keck Center for Integrative Neuroscience at UCSF. "This is an important fact to consider, given that we increasingly live in a more demanding, high-interference environment, with a dramatic increase in the accessibility and variety of electronic media and the devices that deliver them, many of which are portable." In addition to the research studies, Gazzaley's team is exploring the potential of software brain-training programs to help older people improve their ability to mentally process tasks simultaneously. "The ability to dynamically update working memory is critical to cognitive function," he said. The study was funded by the National Institutes of Health, the American Federation of Aging Research and a University of California Presidential Postdoctoral fellowship to Clapp. The other co-authors were Michael T. Rubens and Jasdeep Sabharwal of the Gazzaley lab. Link: http://www.sciencedaily.com/releases/2011/04/110411152522.htm
lemur Posted April 18, 2011 Posted April 18, 2011 I always thought this had to do with the development of depth-of-thought and critical thinking skills that come with life experience and experience with reasoning and logic. I noticed that when I was a younger student, I could read pages and pages of relatively esoteric academic writing and absorb it at a more superficial level but as I gained critical thinking/reading skills, I would have to slow down reading so I could think about each sentence in depth in terms of what it means, what evidence could support it or call it into question. I had the idea that multitasking and other superficial interactions work easier for younger people for the same reason. I.e. an experienced adult's mind continues to critically process information fragments it gets because it has more experience with making in-depth sense out of them and formulating adequate responses. Younger people, on the other hand, will just receive a piece of information and think, "ok, got it." They're not thinking about what it means or the implications as much because they don't have (much) experience with those. Information is more or less context-free in their minds because they haven't had loads of pattern-repitition and similar argumentation with similar concepts. With adults, however, it often can take only a single word or phrase to evoke an entire discourse. Could this be related to the biological aspect discussed in the OP in some way? 1
michel123456 Posted April 18, 2011 Posted April 18, 2011 Isn't it about Attention Deficit Disorder, ADD?
lemur Posted April 18, 2011 Posted April 18, 2011 Isn't it about Attention Deficit Disorder, ADD? Some kinds of multitasking require more attention. E.g. if you want to get a lot of chores done at the same time, you have to keep track of the process of each activity while you're doing other things at the same time. You can't let food burn or clothes spoil in the washing machine, etc. while you're getting yourself and kids ready for an activity and trying to wash dishes.
Athena Posted April 18, 2011 Posted April 18, 2011 (edited) This change in brain function has employment ramifications. There are some jobs better suited for older people and some are better suited for younger people. Good luck training older people to be better multitaskers. I don't think this is going to happen, because of changes in brain metabolism. http://onlinelibrary...m.1444/abstract That is only part of the story. There are other aspects in brain metabolism as well. I think we need to consider energy conservation. Our brain does a few things to conserve energy, and if it did not, we would have short life spans. For example, we generalize rather then see every tree or every human as individuals we are learning for the first time. We see all trees, all Mexicans, all Jews, all men, all women, etc. not individuals we are learning of for the first time, as a young child is learning all these things for a first time. That is distinctly a brain slow down. When we learn to drive a car, we have to think about so many things, that later become automatic. Imagine trying to drive if every time took the same effort as the first time! When we learn a new route from home to work, our brains are working very hard, and later we drive the route on automatic. A major change in brain function happens around age 8, and this is very important to conserving energy and living longer. I would assume the later changes also serve the same function of conserving energy, only now we have less energy in general, and just getting through the day can be challenging. A morning of heavy thinking can make a nap unavoidable. For sure my thinking is not as good in the evening as in the morning when I am full of energy. I experimented with pot when I was young because I was told it improve my concentration. It improved my concentration too much. Instead of reading dog, I read d o g. When our energy is low and we slow down too much, it seems to take even more effort for d o g to be dog. Now, throw in a physical distraction like pain or hunger, and we get d o huh, pain, hunger, d o, d o, d oh forget it, I am going to eat, take a pain pill and then take a nap. Not so different from my experience of smoking pot. Edited April 18, 2011 by Athena
TonyMcC Posted April 18, 2011 Posted April 18, 2011 (edited) There is a commonly held belief that women multitask better than men. http://www.telegraph.co.uk/science/science-news/7896385/Scientists-prove-that-women-are-better-at-multitasking-than-men.html Perhaps that explains why I, as an older than average male, don't do very well if I play poker at the same time as giving attention to this site. (lol). Edited April 18, 2011 by TonyMcC
ewmon Posted April 19, 2011 Posted April 19, 2011 the people who multitask most frequently think they're actually the best at it, and in fact, they're the worst at it. In fact, all the evidence we have suggests that the people who multitask the most actually are the least capable of any important aspect of multitasking.: we actually have studies that look at the most fundamental things one needs to be able to do to multitask: filter out irrelevancy, manage your short-term memory well and actually how rapidly ... you switch tasks. And in all of these cases, even when they're not multitasking, multi-taskers are just much worse at it. —Does Multitasking Lead To A More Productive Brain?
lemur Posted April 19, 2011 Posted April 19, 2011 I've known people who multitask by, for example, comprehending the minimum possible amount of talk-information being given to them. So, for example, they are listening well enough to the flow of talk to nod, express surprise, interest, etc. but then when asked about what was said, they don't actually know. So, in fact, they're not really paying attention to multiple things at the same time - they're just interacting at a very minimal level with one or more, and perhaps shifting critical attention between several. I think this is how some people can listen to music or watch TV while doing homework or something else that requires more intensive attention. They aren't concentrating on all the parts and lyrics in the music or the details of what's on TV - it's just background noise for them and somehow they can be interested enough at that superficial level to enjoy having it on yet it doesn't distract them from their work. A strange behavior, imo, though seemingly very common for many people.
thinker_jeff Posted April 19, 2011 Author Posted April 19, 2011 I always thought this had to do with the development of depth-of-thought and critical thinking skills that come with life experience and experience with reasoning and logic. I noticed that when I was a younger student, I could read pages and pages of relatively esoteric academic writing and absorb it at a more superficial level but as I gained critical thinking/reading skills, I would have to slow down reading so I could think about each sentence in depth in terms of what it means, what evidence could support it or call it into question. I had the idea that multitasking and other superficial interactions work easier for younger people for the same reason. I.e. an experienced adult's mind continues to critically process information fragments it gets because it has more experience with making in-depth sense out of them and formulating adequate responses. Younger people, on the other hand, will just receive a piece of information and think, "ok, got it." They're not thinking about what it means or the implications as much because they don't have (much) experience with those. Information is more or less context-free in their minds because they haven't had loads of pattern-repitition and similar argumentation with similar concepts. With adults, however, it often can take only a single word or phrase to evoke an entire discourse. Could this be related to the biological aspect discussed in the OP in some way? Good question. Logically it is possibly related to the biological effect in this research. There are three possibilities underpinning the difficulty of multitasking for olders. The first, it could be the functional degeneration in the memory system, especially in the working memory system. That means the neural connections between the multitasks are weaker than youngers'. The second possibility could be that attentional function in older's brain is somehow stronger than in younger's. Because the olders focus the current event so much they are not so easy to redraw their attention from that. The stronger attention should help to think deeper on the current event. The third one could be the combination of the first and the second, which means the olders have the functional degeneration in memory system and the reinforced attentional function. We need more research to confirm the possibilities.
lemur Posted April 19, 2011 Posted April 19, 2011 Good question. Logically it is possibly related to the biological effect in this research. There are three possibilities underpinning the difficulty of multitasking for olders. The first, it could be the functional degeneration in the memory system, especially in the working memory system. That means the neural connections between the multitasks are weaker than youngers'. The second possibility could be that attentional function in older's brain is somehow stronger than in younger's. Because the olders focus the current event so much they are not so easy to redraw their attention from that. The stronger attention should help to think deeper on the current event. The third one could be the combination of the first and the second, which means the olders have the functional degeneration in memory system and the reinforced attentional function. We need more research to confirm the possibilities. Could the two be potentially related? I heard that as nerves develop, the shielding between them grows so that they are less likely to make connections, whereas the transmission ability of the mature, well-shielded nerves becomes better (more practiced/honed?) in its functioning.
thinker_jeff Posted April 19, 2011 Author Posted April 19, 2011 Could the two be potentially related? I heard that as nerves develop, the shielding between them grows so that they are less likely to make connections, whereas the transmission ability of the mature, well-shielded nerves becomes better (more practiced/honed?) in its functioning. I guess what you are talking about is myelination. This developing process should be completed in the adolescent stages of life. To the subjects in this research, both of the olders and youngers are well done for that, which means no difference between them. http://en.wikipedia.org/wiki/Myelination
lemur Posted April 19, 2011 Posted April 19, 2011 I guess what you are talking about is myelination. This developing process should be completed in the adolescent stages of life. To the subjects in this research, both of the olders and youngers are well done for that, which means no difference between them. http://en.wikipedia....iki/Myelination Even in the more cognitively intensive concentrations of nerve cells (frontal lobe?). Sorry if this is covered by your link. I'll check it out later but I don't have time at this moment.
thinker_jeff Posted April 19, 2011 Author Posted April 19, 2011 Even in the more cognitively intensive concentrations of nerve cells (frontal lobe?). Sorry if this is covered by your link. I'll check it out later but I don't have time at this moment. Yes.
Recommended Posts