Short-term Memory

Not every piece of information registered by our senses gets attended to — in fact, most of it does not. Only the information we actually attend to moves on from the sensory registers into the second memory store, short-term memory (STM). STM holds a small amount of information for a brief period, usually thirty seconds or less. Atkinson and Shiffrin proposed that information in STM is mainly encoded acoustically, that is, in terms of how it sounds, and that unless it is continuously rehearsed it will typically be lost from STM within that thirty-second window. STM is a fragile store, though notably less fragile than the sensory registers, where information decays automatically in under a second regardless of what a person does. STM's fragility, and the fact that only attended-to information reaches …