Perception: Attention Experiments Intro Psych Mar 3, 2010 Class #18

How important is attention? 1987 Northwest Airlines jet from Detroit crashed moments after take-off 154 passengers and crew, 2 on ground, died

Attention Close or careful observation or mental concentration. The ability or power to concentrate mentally (Webster’s New Dictionary) A selective narrowing or focusing of consciousness (Merriam-Webster’s)

Different Aspects of Attention Selective Attention Visual Auditory Divided Attention Automatic Processing

Selective Attention Focusing our awareness on only part of everything we are experiencing Trying to attend to one task over another…. Difficult to attend to more than one thing at the same time

Selective Attention – Visual Neisser et al. (1979) Lets see how our class does… In this one minute video, there will be two basketball teams One team is wearing black shirts, the other is wearing white shirts Pick either team and count the number of passes that are made by that particular team

Sights unseen??? Mack and Rock (1998) Research on a phenomenon known as inattentional blindness suggests that unless we pay close attention, we can miss even the most conspicuous events Participants were asked to focus on a cross They often failed to notice an unexpected object, even when it had appeared in the center of their field of vision

Selective Attention (Auditory) Dichotic listening task (Cherry, 1953) Any task where two streams of auditory information are presented simultaneously, one to each ear (generally over headphones). Subjects are required to attend to one ear only. Shadowing task -- Two messages played, one to each ear. One message has to be "shadowed" by the subject (repeated back out loud). This is called the “attended message.

Cherry (1953) Cherry: Early researcher on selective attention. Posed question: Q: How can one attend to a single conversation in a room of simultaneous conversations (cocktail party effect)? A: By making use of physical differences - sex of speaker, voice intensity, location of speaker etc. If two messages are presented simultaneously in the same voice, separating the messages is very difficult.

In Shadowing Task… Listeners seldom noticed the unattended message being in a foreign language or in reversed speech However, they nearly always noticed physical changes in the unattended message Cherry’s conclusion? People can shadow accurately but its not easy Unattended auditory information receives very little processing

Treisman (1960) Experiment 1 Subjects asked to shadow a story being presented to one ear. At some point, the story was switched to the unattended ear. What do you think happened? Experiment 2 Attended ear: Dear…3…Jane Unattended ear: 7…aunt…10 What do you think happened?

Effects of an Unattended Word MacKay (1973): Experiment 1 Attended Ear: “The boy threw a rock at a bank” Unattended Ear: “Scissor...ladder…money…finger Question: Where did the boy throw the rock? Answer: At a financial bank

Effects of an Unattended Word MacKay (1973): Experiment 2 Attended Ear: “The boy threw a rock at a bank” Unattended Ear: “ Scissor...ladder…river…finger Question: Where did the boy throw the rock? Answer: At the riverbank In both MacKay experiments, unattended message influenced interpretation of attended message

Divided Attention Trying to attend to two stimuli at once and making multiple responses rather than making one response to multiple stimuli Performing more than one activity at a time. Can be done when at least one task is so automatic it requires little or no attention Can be very difficult Can also be accomplished on two tasks that require attentional focus if it taps into different kinds of attentional resources

Divided Attention Shadowing Task “the Mets will win it all this year...” “Dr. Weiss is the toughest teacher at Adams State College ……” “Dr. Weiss, uh what?”

Automatic Processing Does not require attention Example: Driving a car & listening to the radio Example: Reading (as in the Stroop task) Parallel Processing The ability to search for things rapidly and automatically (effortless) Reber (1967) Implicit or automatic processes allow us to be experts – more efficient

Some drawbacks??? Once automatic, hard to unlearn… Any examples of when this might be a problem? Everyday attentional slips Driving down familiar road when you should be taking the next road… Maybe part of what happened to Northwest Airlines tragedy in 1987 Can make it difficult to attend when you really need to…