Visual working memory, which can only hold three of four objects at a time, is thought to be based on synchronized brain activity across a network of brain regions. Now a new study has allowed us to get a better picture of how exactly that works. Both the maintenance and the contents of working memory were connected to brief synchronizations of neural activity in alpha, beta and gamma brainwaves across frontoparietal regions that underlie executive and attentional functions and visual areas in the occipital lobe. Most interestingly, individual VWM capacity could be predicted by synchrony in a network centered on the intraparietal sulcus.
Human working memory is based on dynamic interaction networks in the brain
Reference
Palva, M., Monto, S., Kulashekhar, S., & Palva, S. (2010). Neuronal synchrony reveals working memory networks and predicts individual memory capacity. Proceedings of the National Academy of Sciences, 107(16), 7580-7585. Retrieved from http://www.pnas.org/content/107/16/7580.abstract
Related News
Easy Solution for Test Anxiety
It’s well known that being too anxious about an exam can make you perform worse, and studies indicate that part of the reason for this is that your limited working memory is being clogged up with thoughts related to this anxiety. However for those who suffer from test anxiety, it’s not so easy to simply ‘relax’ and clear their heads. But now a new study has found that simply spending 10 minutes before the exam writing about your thoughts and feelings can free up brainpower previously occupied by testing worries.
Computer-based program may help ADHD symptoms in children
A working memory training program developed to help children with ADHD has been tested by 52 students, aged 7 to 17. Between a quarter and a third of the children showed significant improvement in inattention, overall number of ADHD symptoms, initiation, planning/organization, and working memory, according to parental ratings. While teacher ratings were positive, they did not quite reach significance. It is worth noting that this improvement was maintained at the four-month follow-up.
Clarity in short-term memory shows no link with IQ
The number of items a person can hold in short-term memory is strongly correlated with their IQ. But short-term memory has been recently found to vary along another dimension as well: some people remember (‘see’) the items in short-term memory more clearly and precisely than other people. This discovery has lead to the hypothesis that both of these factors should be considered when measuring working memory capacity. But do both these aspects correlate with fluid intelligence?
Compound in celery, peppers reduces age-related memory deficits
Inflammation in the brain appears to be a key contributor to age-related memory problems, and it may be that this has to do with the dysregulation of microglia that, previous research has shown, occurs with age. As these specialized support cells in the brain do normally when there’s an infection, with age microglia start to produce excessive cytokines, some of which result in the typical behaviors that accompany illness (sleepiness, appetite loss, cognitive deficits and depression).
Insulin sensitivity may explain link between obesity, memory problems
Previous research has indicated that obesity in middle-age is linked to higher risk of cognitive decline and dementia in old age. Now a study of 32 middle-aged adults (40-60) has revealed that although obese, overweight and normal-weight participants all performed equally well on a difficult cognitive task (a working memory task called the 2-Back task), obese individuals displayed significantly lower activation in the right inferior parietal cortex.
Sharpening your brain through talking
Following on from earlier research suggesting that simply talking helps keep your mind sharp at all ages, a new study involving 192 undergraduates indicates that the type of talking makes a difference. Engaging in brief (10 minute) conversations in which participants were simply instructed to get to know another person resulted in boosts to their executive function (the processes involved in working memory, planning, decision-making, and so on).
Distinguishing between working memory and long-term memory
Because people with damage to their hippocampus are sometimes impaired at remembering spatial information even over extremely short periods of time, it has been thought that the hippocampus is crucial for spatial information irrespective of whether the task is a working memory or a long-term memory task. This is in contrast to other types of information. In general, the hippocampus (and related structures in the mediotemporal lobe) is assumed to be involved in long-term memory, not working memory.
New advice on how much cognitive abilities decline with age
Reports on cognitive decline with age have, over the years, come out with two general findings: older adults do significantly worse than younger adults; older adults are just as good as younger adults. Part of the problem is that there are two different approaches to studying this, each with their own specific bias. You can keep testing the same group of people as they get older — the problem with this is that they get more and more practiced, which mitigates the effects of age.
Natural scenes have positive impact on brain
A couple of years ago I reported on a finding that walking in the park, and (most surprisingly) simply looking at photos of natural scenes, could improve memory and concentration (see below). Now a new study helps explain why. The study examined brain activity while 12 male participants (average age 22) looked at images of tranquil beach scenes and non-tranquil motorway scenes.
Friends, family detect early Alzheimer's signs better than traditional tests
Confirming earlier research, a study involving 257 older adults (average age 75) has found that a two-minute questionnaire filled out by a close friend or family member is more accurate that standard cognitive tests in detecting early signs of Alzheimer’s.
The AD8 asks questions about changes in everyday activities: