Monday, June 29, 2009
Remember to forget and forget to remember
But wait again! What do these researchers say?
"It's somewhat of a counter-intuitive idea," said Brice Kuhl, a doctoral student working in the lab of Associate Professor Anthony Wagner of the Psychology Department. "Remembering something actually has a cost for memories that are related but irrelevant." But this cost is beneficial: The brain's ability to weaken unimportant memories and experiences enables it to function more efficiently in the future, Kuhl said.
Eh? 'Counter-intuitive'? To whom?
It reflects rather poorly on people working in the field when this kind of thing comes up and when it makes news, as if it actually were news.
Here's the abstract:
Remembering often requires the selection of goal-relevant memories in the face of competition from irrelevant memories. Although there is a cost of selecting target memories over competing memories (increased forgetting of the competing memories), here we report neural evidence for the adaptive benefits of forgetting—namely, reduced demands on cognitive control during future acts of remembering. Functional magnetic resonance imaging during selective retrieval showed that repeated retrieval of target memories was accompanied by dynamic reductions in the engagement of functionally coupled cognitive control mechanisms that detect (anterior cingulate cortex) and resolve (dorsolateral and ventrolateral prefrontal cortex) mnemonic competition. Strikingly, regression analyses revealed that this prefrontal disengagement tracked the extent to which competing memories were forgotten; greater forgetting of competing memories was associated with a greater decline in demands on prefrontal cortex during target remembering. These findings indicate that, although forgetting can be frustrating, memory might be adaptive because forgetting confers neural processing benefits.
Not only is the notion that things should be so anything but counter-intuitive, but it is an almost obvious consequence of the finitude of brain capacity—in terms of storage and processing; a separation of functions that is probably meaningless, but this is still the way people think about it, so I'm using that kind of model—and should have been self-evident, and not in need of fMRI confirmation, to anyone working in the study of attention, and those in the neural networks community should not exactly find themselves surprised.
Still, putting all this aside, with this confirmation, if it were needed, of the obvious, maybe some people will start paying attention to the facts, rather than the obsession, in science and pop culture alike, with trying to force people at all stages in lifr, and especially the 'later' ones, into a mode where the kind of memory common to the early stages of life—when acquisition, storage and recall of items of what you might call 'random' nature, as opposed to those contextually set, is at its peak; and understandbaly so—is touted as something that needs to be trained in order to retain mental capability into the later years of one's life.
That never made sense, at least not to me. I've always thought that, given the limited capacity of the brain, there really was no option but to discard other items. In the course of one's life, things come and things go; and one's identity, which is intimately liked to one's memories, to the extent that one might be tempted assert that the two are in a real sense identical, cannot really be expected to be any different.
Of course, before this filters through to the common man through the pop media and the self-interested propganada of a whole range of private, academic and governmental organizations, it'll be a while. Much the same, I suspect, as will be the case in the new research coming out in relation to the whole antioxidant craze.
Those interested in memory might also be interested in this article.
Posted by T at 06:39