Textbook Notes (369,133)
Canada (162,403)
Psychology (3,337)
PSYC 2410 (149)
Chapter 4

Chapter 4 notes.docx

4 Pages

Course Code
PSYC 2410
Anneke Olthof

This preview shows page 1. Sign up to view the full 4 pages of the document.
Cognitive Psychology: Chapter 4 Selective Attention - Selective attention refers to the skill through which one focuses on one input or one task while ignoring other stimuli - Attention studies sometimes employ a task known as shadowing  Using headphones, different information is presented to each ear. This is known as dichotic listening  The participant pays attention to the information presented to one ear (the attended channel) while ignoring information presented to the other (the unattended channel) - Results from these studies suggest that unusual characteristics of the unattended channel go unnoticed - Similar effects happen in visual studies (Ex. In a classic study, participants asked to count the number of basketball passes) - There are some important exceptions, where certain pieces of information will be unnoticed even if the presented to the unattended channel  The participants own name, or any words of high personal significance, will be noticed even in the unattended channel - This pattern is observed in real-life situations and sometimes called the cocktail party effect - Sometimes effects of attention are so strong that we fail to see stimuli that are directly in front of our eyes - For instance, if participants are asked to look at a fixation target while attending to another part of the screen, they may fail to notice changes in shape to the fixation target. This phenomenon is known as inattentional blindness - From studies of inattentional blindness, one might be tempted to conclude that there is “no perception without attention” - However, other studies demonstrate that unconscious perception still occurs in the absence of attention - For example, participants’ judgements of line length are influenced by the presence of “fins” that cause the Muller-Lyer illusion, even if they do not consciously see the fins - Other studies of attention focus on a phenomenon known as change blindness, the inability of observers to detect changes in scenes they are looking directly at - We recognize things more easily when it’s in the middle of the scene, and not in the periphery - Similar effects of change blindness occur when people fail to notice continuity errors in films - In a particularly striking example, participants failed to notice when the person asking them for directions changed identity (following a brief interruption by two people carrying a door) - Each study of attention focused on when the perceiver selects the desired input - According to the early-selection hypothesis, the unattended input receives little to no analysis - According to the late-selection hypothesis, all input receives analysis but only the attended input reaches consciousness or is remembered - Both early- and late-selection hypotheses capture part of the truth • For instance, the study discussed earlier showing that unattended stimuli have effects on perception seems to be a case of late selection • However, the electrical activity of the brain for attended versus unattended inputs differs within 70ms of stimulus presentation, suggesting early selection - An experiment by Posner and Snyder (1975) illustrates that there are two kinds of priming related to attention - One kind of priming is stimulus-based (repetition-based priming), the other is expectation-based (basically ready for the stimulus, waiting for it to happen) - For this type of study, the dependent variable is the response time to make a decision about the stimuli - Posner and Snyder (1975) found in the low-validity condition that the primed condition was faster than neutral • This demonstrates an effect of repetition priming; the receptors were “warmed up” - But, the misled condition was not any slower than neutral • Warming up the “wrong” detector does not take activation away from the correct one - Posner and Snyder (1975) found in the high-validity condition that the primed condition was much faster than neutral • This demonstrates an additional effect of expectation in addition to repetition priming - Further, the misled condition was slower than the neutral condition • Expectation is limited in capacity; the “wrong” expectation interferes with activating the correct detectors - You can’t expect two things to happen… When watching and waiting for one thing to happen, you can’t pay attention to another thing; therefore you can’t expect the other thing to happen - Studies of spatial attention examine the ability to focus on a particular position in space and to be prepared for stimuli appearing in that position - For example, when detecting a stimulus on the right or left side of the screen, participants benefit if an arrow provides
More Less
Unlock Document

Only page 1 are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.