Memory, sensory
From WikEd
Contents |
What is sensory memory?
Sensory memory allows us to take a 'snapshot' of our environment, and to store this information for a short period. Only information that is transferred to another level of memory will be preserved no more than for a two seconds. Sensory memory holds a short impression of sensory information even when the sensory system does not send any information anymore. Sensory memory is affiliated with the transduction of energy (change from one energy from to another). The environment makes available a variety of sources of information (light, sound, smell, heat, cold, etc.), but the brain only understands electrical energy. The body has special sensory receptor cells that transduce (change from one form of energy to another) this external energy to something the brain can understand. In the process of transduction, a memory is created. This memory is very short (less than 1/2 second for vision; about 3 seconds for hearing).
How does it work?
There are several models that attempt to explain the process:
Levels of Memory
The environment stimulates one or more sensory systems. This environmental information then passes into three levels of memory called sensory memory, short-term memory and long-term memory. (The classical theory of Richard C. Atkinson and Richard M. Shiffrin illustrates the information-processing approach)
Sensory Memory
Sensory memory is the first level of memory. Sensory memory retains the brief impression of a sensory stimulus after the stimulus itself has ended. Imagine, you see an object. When the object has disappeared, it may still be vivid in your memory.
The sensory memory act as a buffer for stimuli received through the senses. A sensory memory exists for each sensory channel: iconic memory for visual stimuli, echoic memory for aural stimuli and haptic memory for touch. Information is passed from sensory memory into short-term memory by attention, thereby filtering the stimuli to only those which are of interest at a given time. Attention, which selectively determines what will 'get through' for further examination and what will not, allows us to focus on parts of the stimulus and thereby to recognize some of its features.
Evidence of Effectiveness
Sperlings research on Iconic memory
Sperling ran a more systematic study of this effect in 1960. His experiment involved briefly presenting a grid of three rows of four letters for 50ms to volunteers. In one condition he asked participants to report as many letters as they could remember after the letters had been presented. In another he indicated, after the presentation of letters, which row of letters (first, second or third) he would like participants to try to recall. Sperling found that while participants could only report an average of four letters in the first condition, they usually successfully recalled the four letters of the chosen row in the second condition, even though they were only told which to report after the whole letter grid was presented. This suggests that for a brief period of time the whole grid was accessible to the participants as sensory memory.
What are the characteristics?
There are various specific issues about sensory memory:
A. It is a high capacity form of memory registration of visual data.
B. Information in the sensory memory is un-interpreted.
C. Sensory memory is short; visual information, for example, fades away in less than a second.
APPLICATIONS: In Transactional Analysis, sensory information that is stored in one's long-term memory makes up the "Child" part of his personality. This memory results in a reproduction of what a child felt, saw, heard and understood during their first five years of life. Understanding that part of a student's personality may allow a teacher to better handle discipline problems in the classroom. Janet Vallowe
