The subtle difference between learning and relearning
Although learning and memory were recently shown to be linked to the changes in brain structure mentioned above, many questions still remain unanswered. What happens, for example, when the brain learns something, forgets it after a while and then has to learn it again later? By way of example, we know from experience that, once we have learned to ride a bicycle, we can easily pick it up again, even if we haven't practiced for years. In other cases too, "relearning" tends to be easier than starting "from scratch". Does this subtle difference also have its origins in the structure of the nerve cells?
Cell appendages abide the saying "a bird in the hand "
Scientists at the Max Planck Institute of Neurobiology have now managed to show that there are indeed considerable differences in the number of new cell contacts made - depending on whether a piece of information is new or is being learned second time around. Nerve cells that process visual information, for instance, produced a considerably higher number of new cell contacts if the flow of information from their "own" eye was temporarily blocked. After approximately five days, the nerve cells had rearranged themselves so as to receive and process information from the other eye - the brain had resigned itself to having only one eye at its disposal. Once information flowed freely again from the eye that had been temporarily closed, the nerve cells resumed their original function and now more or less ignored signals from the alternative eye.
"What surprised us most, however, was that the majority of the appendages which developed in response to the information blockade, continu
|Contact: Dr. Mark Huebener|