PSYC305-Attention_L3 Majdi example.ppt

Attention Lecture 3 Mariana V. C. Coutinho, PhD Week 6 Let’s begin with an example… Majdi like many of you, went to the library to complete his homework. He was able to ignore the people talking when he was doing his math homework. But became distracted by the talking when he was playing a relativel...

Attention Lecture 3 Mariana V. C. Coutinho, PhD Week 6 Let’s begin with an example… Majdi like many of you, went to the library to complete his homework. He was able to ignore the people talking when he was doing his math homework. But became distracted by the talking when he was playing a relatively easy game on the phone. Question What determines whether one succeeds in ignoring distractor stimuli? What determines whether one succeeds in ignoring distractor stimuli? The following two factors are important: Processing capacity of the cognitive system Perceptual load of the task Processing Capacity Processing capacity refers to the amount of information people can handle. In other words, it refers to how much information can be processed by the cognitive system at a time. Processing Capacity You probably know that … People cannot process unlimited number of items at a time. The processing capacity of our cognitive system is limited. What determines whether one succeeds in ignoring distractor stimuli? The following two factors are important: Processing capacity Perceptual load Perceptual Load Perceptual Load Easy Tasks = Low perceptual Load Difficult Task = High Perceptual Load Here is an example of: Easy Task Low Perceptual Load Difficult Task High Perceptual Load Perceptual Load For example: participants were asked to respond as quickly as possible when they identified a target, either X or N. Low Perceptual Load Task High Perceptual Load Task Going Back to the Question What determines whether one succeeds in ignoring distractor stimuli? The Answer is: It depends on how much processing resources (capacity) has been allocated to the task. If most resources available were allocated, then distractors will not interfere. People will be able to ignore distractors. Answer cont. On the other hand, if fewer resources were allocated, distractors are more likely to interfere. People will be less likely to ignore distractors. For example: Suppose the circles below represent processing capacity. For example: Green color refers to how much resources have been used by the task. For example: Example A: few processing resources used Example B: all resources used For example: In which of these cases, participants are less likely to be affected by the distractor? For example: In which of these cases, the distractor is less likely to be noticed? For example: In which of these cases, the distractor is less likely to be noticed? The correct answer is B because there are no processing resources available to process the distractor stimulus. Going back To Majdi example… Why the conversation ( distractor) interfered with playing on the phone but not with the math homework? Majdi Example Playing in the phone did not use all resources. Majdi Example Why the conversation ( distractor) interfered with playing on the phone but not with the math homework? Math homework used all resources. Question about Divided Attention Can We Attend to More Than One Thing at a Time? Divided Attention Can We Attend to More Than One Thing at a Time? For example: People can simultaneously drive, have conversations. Divided Attention The ability to divide attention depends on how much processing resources is required to perform each task. Divided Attention If each task requires minimum processing resources, then you should be able to do both. Task 1 Task 2 Divided Attention On the other hand, if each task is very taxing (uses up most processing resources), most likely you will not be able to both. Task 1 Task 2 It is important to add that how much processing resources a task uses up depends on level of difficulty practice An Easy task uses up less resources than a difficult task Well-practiced task uses up less resources than recently learned task Thank you!