Perceptual priming tasks
From Psy3242
Contents |
Definition of Priming
Priming is a phenomenon of long-term memory that typically increases or decreases an individual's ability to process repeated stimuli, usually consisting of words, ideas, or pictures. Most long-term memory tasks such as this are comprised of three phases: 1) a study phase, 2) a retention interval in which a diversion task is performed, and 3) a test phase in which memories of the previously studied material are retrieved. Priming is often described as a manifestation of implicit memory. One of its properties is that the remembered stimulus is often better remembered later in the form in which it was originally experienced. For example, if a stimulus was given in an auditory form, a later auditory cue would produce more successful performance than a visual cue. Priming can also be used in experimental form whereby a stimulus is presented to a subject to sensitize to a later presentation of the same stimulus or a similar one. Presentation of a particular word such as 'chair' in a list of priming words will later raise the probability of the subject answering with that word when asked to think of a word beginning with the fragment 'cha'.
Perceptual Priming
Certain priming tasks are considered to be primarily perceptual in nature, drawing upon processes concerned with the visual, auditory, and tactile forms of a target stimulus. These include word and picture identification, lexical decision, picture and word naming, degraded picture and word naming, completing word-stems, anagram solution, and word-fragment completion. Perceptual priming is sensitive to the exact format and modality of a certain stimulus.
The Lexical Decision Task
This basic procedure is often used in association with priming tasks in psychology, and it involves measuring how quickly people classify given stimuli as words or non-words. The task originally was used in the 1970's in studies on the structure of semantic memory, and since then it has been widely used in the field of psychology.
In such a task, a subject is presented with a visual or auditory string of words or pseudowords (nonsense) and then asked to indicate whether the stimulus was a word or not. Analysis of this data is based on reaction times and error rates, and is significant in showing that subjects are faster to respond to words when they are first shown a semantically related prime stimulus.
Perceptual Priming and Memory
One important aspect of priming refers to the relative success with which amnesics perform on tasks compared to control subjects. Studies have indicated that they too remember stimuli on previous study lists even though they have no conscious recollection of having seen the list itself. However, visual priming in amnesics relies heavily on the use of existing memory, since amnesics cannot be primed using words they were never familiar with in the past, and yet normal priming can be experienced in auditory tasks.
