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Showing posts from August, 2017

Do We See the World Like a Movie?

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We have the feeling that we experience the world like a continuously sampled data stream. If we perceive multiple objects of events seemingly at the same time, we may actually be multiplexing the several data streams; that is, we take a sample from one data stream, switch to take a sample from the next stream and so on — all on a millisecond time scale. But another possibility is that we perceive objects and events like a movie frame, where the brain takes working-memory snapshots and plays them in succession. Like still frames in a movie, if played at a high-enough speed, the frames will blend in our mind to give the illusion of continuous monitoring. In either case, we have to account for working memory. That is, we can only hold a small amount of information in our working memory at any one instant, as in being able to dial a seven-digit phone number you just looked up. In the phone number case, does our brain accumulate and buffer the representation of each integer until reaching t...

Is Your Brain Older Than You Are?

"You are as old as you think you are," the saying goes. Well, not quite. You, that is the inner you in your brain, is as old as your brain is. But your brain age may or may not correlate with chronological age. The other day at my gym workout, I again saw a young black guy, built like Captain America, whose workout schedule sometimes overlaps with mine. We had not met, and out of the blue he came up to me and said, “You are my inspiration. You inspire me to be able to work out like you when I get your age.” Wow! I inspire somebody! Then my balloon popped when I realized that he knew I was old just by looking at me. My body may not look like I’m 83, but I guess hair loss and the lines in my face betray me. The point of this story is that the bodily organs do not have the same rate of aging. Skin ages rather conspicuously in most older people. Specific organs may age at different rates depending on what they have been exposed to, for example skin and sun, liver and alcohol, lun...

Mental Down-time Affects Memory

Research has shown that recent experiences are reactivated during sleep and wakeful rest. This "downtime" recall of memories is part of the process for consolidating long-term memory and serves as memory rehearsal that can strengthen the memory. Thus, the old saying, "all work and no play makes Jack a dull boy," might be re-framed, "all work and no rest makes Jack a poor learner." To expand on this idea, a study was conducted to test whether this memory enhancing effect of mental downtime applied to new learning of related material. In other words, does downtime help form memories for new experiences as well as it does for recent past experiences? The researchers hypothesized that the degree to which memory processes are engaged during mental downtime determines whether or not prior knowledge promotes or interferes with new learning. To test this idea, human adults were trained on learning face-object pairs over four repetitions. This initial learning was ...