ATTENTION AND CONSCIOUSNESS What is Attention? ability to focus on a task ability to concentrate refers to the allocation of processing Different Aspects of Attention 1.Selective Attention-difficult to attend to more that thing at the same time trying to attend to one task over another requires selective attention Selective Attention (Visual) classic Stroop task (1935): (show stimuli) slower to name color when word says a different color than to name the color of an colored square why does this happen? reading is an automatic process color naming is a controlled process automatic process of reading interferes with our ability to selectively attend to ink color
2.Divided Attention and Dual Task Performance difficult to attend to more that thing at the same time trying to attend to two stimuli at once and making multiple responses rather than making one response to multiple stimuli (interference) Theoretical Interpretations of Divided Attention Capacity Theories limited amount of resources available to conduct tasks (Kahneman, 1973) multiple resources, only one cognitive process can occur at a time (Pashler) 3. Automaticity;automaticprocessing: does not require attention driving a car & listening to the radio reading (as in the Stroop task) controlled processing: requires attention
SENSATION AND PERCEPTION Sensations can be defined as the passive process of bringing information from the outside world into the body and to the brain. The process is passive in the sense that we do not have to be consciously engaging in a "sensing" process. Perceptioncan be defined as the active process of selecting, organizing, and interpreting the information brought to the brain by the senses. 1) Sensation occurs: a) sensory organs absorb energy from a physical stimulus in the environment. b) sensory receptors convert this energy into neural impulses and send them to the brain. 2) Perception follows: a) the brain organizes the information and translates it into something meaningful.
THEORIES 1) Selective Attention - process of discriminating between what is important & is irrelevant and is influenced by motivation. For example - students in class should focus on what the teachers are saying and the overheads being presented. 2) Perceptual Expectancy - how we perceive the world is a function of our past experiences, culture, and biological make up.
THRESHOLDS OF SENSATION 1) Threshold - a dividing line between what has detectable energy and what does not. 2) Difference Threshold - the minimum amount of stimulus intensity change needed to produce a noticeable change. the greater the intensity (ex., weight) of a stimulus, the greater the change needed to produce a noticeable change.
3) Signal-Detection Theory - detection of a stimulus involves some decision making process as well as a sensory process. Additionally, both sensory and decision making processes are influenced by many more factors than just intensity.
a) Noise - how much outside interference exists.
b) Criterion - the level of assurance that you decide must be met before you take action. Involves higher mental processes. You set criterion based on expectations and consequences of inaccuracy.
PERCEPTION Perception is the process by which organisms interpret and organize sensation to produce a meaningful experience of the world. GESTALT PRINCIPLES OF GROUPING-roughly translates to "whole" or "form," and the whole is greater than the sum of its parts. In order to interpret what we receive through our senses, they theorized that we attempt to organize this information into certain groups. This allows us to interpret the information completely without unneeded repetition.
PERCEPTION A) Gestalt Principles of Perceptual Organization figure-ground - this is the fundamental way we organize visual perceptions. When we look at an object, we see that object (figure) and the background (ground) on which it sits. 2) simplicity/pragnanz (good form) - we group elements that make a good form. However, the idea of "good form" is a little vague and subjective. 3) proximity - nearness=belongingness. Objects that are close to each other in physical space are often perceived as belonging together. 4) similarity - States that objects that are similar are perceived as going together.
5) continuity - we follow whatever direction we are led. 6) common fate - elements that move together tend to be grouped together. 7) closure - we tend to complete a form when it has gaps.