Essential Characteristics of Sensory Memory

Sensory memory is said to be a human's most basic and primal form of memory. A sensory memory is described as a buffer from our actual experiences to the experiences we recall in short- and long-term memories. Sensory memories consist of all of the sensory information that takes place during an experience, and our perception and attention shapes how and if these memories are stored.

Attention

• Attention is the process of converting sensory memories to short-term or long-term memories via conscious perception of a given event. This filters out other stimuli that we do not wish to recall, or has no use to us in the future, and leaves us only with the short-term perception and memory of the event.

Other Classifications

• Sensory memory can be sub-classified into iconic memory, or visual memory; echoic memory, or memories of sounds; and haptic memory--memories associated with touch.

Brain Chemistry

• Sensory memory can be thought of as an ultra short-term memory, which begins to degrade in about half a second after being processed (or not processed) by the hippocampus and amygdala, the brain's center for many functions including memory. Sensory memory related to smells is often better recalled because of the hippocampus and amygdala's close proximity (just two or three synapses) to the olfactory bulb and olfactory cortex, the parts of the brain needed for recalling sensory memories of smell.

Sperline Research

• Research conducted by George Sperline in the 1960s experimented with large, rapidly flashing arrays of numbers which participants were then asked to recall. It was concluded that short-term memory was only able to identify an average of 12 items, but participants often said they could "see" arrays of numbers, just not recall them. These visions were considered the earliest recognition of iconic or visual sensory memories.