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3.Information processing and attention Focused or selective attention refers to the mechanism by which certain information is registered while others are rejected. Capacity or divided attention refers to the upper limit of the amount of processing that can be performed on incoming information at any one time. Many studies of attention have used auditory tasks. Dichotic listening refers to feeding one message into the left ear and a different message simultaneously into the right ear. Participants have to repeat one of the messages aloud. This process is called Shadowing (first used by Cherry). This is a method to study selective attention. Divided attention can be tested using a dual-task technique whereby the individual is asked to attend and respond to both or all incoming messages.

4. Memory In all cognitive operations involving memory 3 different processes are thought to occur. Encoding - It leads to the formation of initial memory traces and receives information from the outside. Storage - Retention of information and maintenance Retrieval - Accessing and recovering information from memory stores   STM LTM Encoding Acoustic Semantic Retrieval Error-free Error-prone Capacity 7+/-2 chunks Unlimited William James divided memory to primary (short term) and secondary memory (long term). In fact 3 forms of memory are now recognised. Sensory memory: This is modality specific, has a larg

2. Basic principles of visual and auditory perception When perceiving an object it needs to be differentiated from its background. Determinants of figure vs. ground differentiation include Contour – surroundedness Size Orientation Symmetry This is also influenced by perceptual set (see below). Reversal of figure-ground perception frequently occurs so that sometimes, the ground is perceived as figure and vice versa e.g. try googling for images of Rubin’s vase illusion. This indicates that same stimuli can produce more than one perception. Figure-ground differentiation is also crucial for perceiving auditory stimuli e.g. when we are at a crowded party we are still able to filter our friend’s voice and have a conversation amidst all noisy background ( cocktail party phenomenon ). Shadowing is an experimental extension of