Final answer:
Sensory memory is a storage system for brief sensory events like sights and sounds. It has a large capacity but retains information for only a few seconds, transferring important data to short-term memory.
Step-by-step explanation:
Sensory Memory
Sensory memory is a part of our memory system that's responsible for storing brief sensory impressions from our environment, such as visual images, sounds, or tastes. It acts as a buffer for stimuli received through the five senses and is capable of holding a large amount of information, but only for a very brief period, typically around a few seconds. This allows us to 'sense' and process a vast array of information at once before deciding what to attend to and what to discard. If deemed important, the data is then transferred to the short-term memory (STM), where it can be consciously considered.
Some features of sensory memory include its large capacity to capture sensory information around us; however, its duration is quite limited, with a retention time of less than a second to a few seconds for different types of sensory information. The format of sensory memory is precise in that it retains the exact replica of the sensory input, such as the intricate visuals of a scene or every pitch and tone in a snippet of conversation. The information that manages to capture our attention moves onto the next stage, which is the short-term memory, capable of holding information for a slightly longer duration—up to about 20 to 30 seconds without rehearsal.
Evidence of Sensory Memory Features
Evidence of the capacity and duration of sensory memory can be found in experiments done by psychologists. For example, George Sperling's iconic experiment in 1960 demonstrated the existence of visual sensory memory, also known as iconic memory. Participants were shown an array of letters for a very short period and could recall only a fraction of them, but when given a cue to remember a specific row immediately after the display vanished, their recall was nearly perfect, showing that all information was indeed captured by sensory memory, albeit for a very short time.