Storage of 7 +/- 2 short-term memories in oscillatory subcycles.
Psychophysical measurements indicate that human subjects can store approximately seven short-term memories. Physiological studies suggest that short-term memories are stored by patterns of neuronal activity. Here it is shown that activity patterns associated with multiple memories can be stored in a single neural network that exhibits nested oscillations similar to those recorded from the brain. Each memory is stored in a different high-frequency ("40 hertz") subcycle of a low-frequency oscillation. Memory patterns repeat on each low-frequency (5 to 12 hertz) oscillation, a repetition that relies on activity-dependent changes in membrane excitability rather than reverberatory circuits. This work suggests that brain oscillations are a timing mechanism for controlling the serial processing of short-term memories.
Lisman
J E
JE
Department of Biology, Brandeis University, Waltham, MA 02254.
Idiart
M A
MA
D003198:Computer Simulation; D005246:Feedback; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D007395:Interneurons / Q000502:physiology; D008564:Membrane Potentials; D008570:Memory, Short-Term / Q000502:physiology*; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D017966:Pyramidal Cells / Q000502:physiology