Class Notes (808,146)
Canada (493,092)
Psychology (4,969)
PSYCH 1X03 (1,053)
Joe Kim (987)
Lecture 11

Lecture 11 Attention Detailed Note.docx

11 Pages
Unlock Document

McMaster University
Joe Kim

1 Psychology Lecture 11: Attention Introduction to Attention  Definition by William James o Everyone knows what attention is. It is the taking possession by the mind in clear form, of one out of what seems several simultaneously possible objects or trains of thought…It implies withdrawal from some things in order to deal effectively with others and is a condition which has a real opposite in the confused, dazed, scatterbrained state  Selection o At the centre of the definition is the concept of selection o Attending to something causes the object of attention to be selected apart from the rest of the unattended objects o Ex. When you first put your clothes on, you can feel the fabric touching your skin o As the day goes on, you are no longer aware of these sensations as other stimuli compete for your attention o Some stimuli in the environment can trigger your attention in an automatic fashion, such as a light flashing  Attention also refers to our conscious ability to attend to information that is relevant to our goals  The irrelevant information in the environment acts as noise that can make it difficult to identify and attend to important information  Nevertheless, we are adept at distinguishing the relevant from the irrelevant information in the environment  Flashbulb memories o A vivid memory that can place you at a significant moment in history o Have a “live” quality, feeling almost as if a person is looking at a photograph of a moment locked in time o However, can be wrong at fine details  Psychologists are interested in understanding how attention shapes our perception and memory and how attentional processes are guided by two competing needs of o Focusing limited mental resources to the immediate task o Monitoring ongoing stimuli to evaluate their potential significant and shjfting the allocation of mental resources when necessary Automatic and Controlled Attention  Automatic and controlled processes are fundamentally different types of processes that influence attention  Automatic processes o Triggered involuntarily by external events and tripped the “capture” of attention o Operate in a fast, efficient and obligatory manner 2  Controlled processes o Guide attention voluntarily and consciously to objects of interest o Operate more slowly because requires cognitive effort  Ex. Driving a car through busy traffic o Controlled processes  While driving, you consciously choose to pay attention to many aspects of the environment to guide this goal-directed behaviour  You choose when to make lane changes, speed up, slow down etc.  So why do we turn down the radio when we are looking for a new address or making an important driving decision?  Demonstrates that it is difficult to consciously attend to many aspects of the task-environment at the same time because the resources for controlled processes are limited o Consider the role of automatic processes in driving  Some cues seem to be more noticeable and lead to stronger and quicker association when paired with events (salience)  It is hard to miss the loud sounds and flashing lights of an emergency vehicle  Second type of automatic process related to learning  Driving is a learned motor skill involving many steps  At first it took a lot of effort to do all those tasks in the correct sequence  However, with enough practice, you can now accomplish all of these little tasks without very much effort  For some people, driving skills have been learned to a point where they can operate on “auto pilot” and report having automatic driving experiences Bottom-Up and Top-Down Processing  Bottom-up processing o Refers to a stimulus driven mechanism in which attention is captured by salient change in the environment o Ex. While enjoying a dinner at a restaurant, you gently rock back and forth on your chair, but go a bit too far o You and your chair fall backwards and hit the floor o Even though there are many interesting sights, sounds and smells happening all over the restaurant, it’s safe to say that the crash instantly captures the attention of everyone o Similarly, bottom-up processing automatically captures your attention to alert you to a police siren, telephone ring and fire alarm  Top-down processing 3 o Instead of a reflexive reaction, you can strategically direct your attention to match your current goals and expectations from past experience through memory o Ex. If you put your keys on the front desk every time you return home, in the morning, when you are a rush and you need your keys, you do not have to do a systematic scan of the entire room o Rather, you can purposely direct your search to the front desk because that’s where the keys are normally found  The selective nature of top-down processing in directing attention contrasts with the automatic nature of bottom-up processing in the capture of attention The Spotlight Model  Just as a physical spotlight illuminates only one part of the stage at a time, your attention spotlight focuses on only part of the environment at a time  Attention can be consciously directed across the visual scene as you look for a friend in a party  Attention can also be hijacked by unconscious processes that can quickly grab your attention so you can avoid an oncoming speeding car as you step off the sidewalk  As your attention moves around your field of vision, objects falling within the spotlight are processed preferentially o You can respond to objects faster and with greater accuracy  Orienting o The act by which attention moves across a scene is known as orienting o Overt attending is obvious because where you are attending is also where you are looking  Example of the chair incident in the restaurant, attention was automatically directed to the location of the accident, which was followed by the movement of every set of eyes in the restaurant o You can also attend to things without looking  Called covert orienting, which reflects “invisible” shifts of attention  Ex. As you wait for Waldo who is late, your gaze may be politely focused on Wayne who is in conversation with you, but your attention covertly shifts toward the door in anticipation of Waldo’s arrival  This improves the chances and speed with which you will notice Waldo when he finally arrives  Spatial Cueing Paradigm (Posner’s experiment) o We can measure attention in the controlled settings of the lab to experimentally manipulate the attention spotlight o As a subject, you are asked to fix your attention to the middle box on the screen o At some point, a target will appear in either the left or right box o It is your job to indicate the correct target location as quickly as possible o However, just before the target appears, a potential target box is briefly flashed o The flashing box serves as a cue for your attention 4 o The target can then follow in either the cued or uncued location o One question that researchers using this paradigm are interested in is measuring the influence of the flashing cue on target detection time o In one experiment, we find that target detection is quicker when it is correctly cued than when it is uncued  The difference in target detection suggests that it is governed by automatic rather than the conscious control of attention  The relatively short time interval between cue and target presentation in this experiment favours automatic rather than consciously controlled processes that guide the allocation of attention  The cue automatically attracts the attention spotlight to the cued location  If a target appears in the cued location, then attention will amplify the perceptual processing of that target and it will be detected quickly  However, if the target appears in the uncued location, the target will be detected more slowly because the attention spotlight will have been directed away from the actual target location  This translates into measureable difference in target detection in the cued and uncued trials o What if the experiment was set up so that the attention cue does provide accurate predictive information about where the target is likely to occur?  In this experimental arrangement, the target appears in the cued location more than 50% of the time  Under many circumstances, consciously controlled shifts of attention can lead to faster responses to targets that appear in the location indicated by the cue than to targets that appear opposite the location indicated by the cue o In all these experiments, predictive cues lead to faster detection time even though the subjects don’t have time to move their eyes to the cued location before making their judgement o However, if the time between the onset of the cue and the target is more than 300 ms (allows sufficient time to direct an eye gaze), subjects are actually slower to detect the target at cued locations than at uncued locations o Known as inhibition of return (IOR)  Occurs when you attempt to redirect to a previously attended location at which the target was not found  Ex. Imagine you are now searching for your friend Waldo who is lost in a large crowd  You know Waldo will be wearing his red hat so you scan the crowd for red items  As a red blur catches the bottom right of your visual field, you turn to look, but quickly realize it is not Waldo, but a red fire hydrant  As you continue searching, IOR tends to prevent your gaze and attention from revisiting the location of the fire hydrant 5  In turn, this promotes orienting towards new and previously unsearched locations, which should result in a more efficient search  Exogenous Vs. Endogenous Cueing o Exogenous cues  Physically orient you to a specific peripheral location  Ex. Cues in spatial cueing paradigm  Seem to automatically capture attention o Endogenous or symbolic cues  Centrally presented cues  Ex. Imagine that instead of having a peripheral box to the left or right light up (exogenous cues), in the centre of the screen is an arrow pointing to the left or right  Unlike exogenous cues, endogenous cues require interpretation  Can be ignored if they conflict with task demands, suggesting they are under volitional control  Top-down processing may be better suited to the processing of exogenous cues, whereas bottom-up processing may be better suited to processing endogenous cues Filter Models  Consider auditory attention  Cocktail Party Effect o Despite competing background noises, a listener can focus on a single channel and still pick out relevant salient information from the background  Colin Cherry conducted classic experiments on the so called “cocktail party” effect, laboratory equivalent is the dichotic listening paradigm o Subjects were asked to listen to two different messages played from a single loudspeaker at the same time o Subjects tried to separate the messages, repeating one, but not the other in the so called “shadowing” task o Cherry’s work revealed that ability to separate target sounds from background noise is based on physical characteristics, such as gender of speaker and direction, pitch or speed of the speech  Cherry’s work inspired the cognitive models that compare attention processes to a filter which sifts away distractions and only allows important information through  Filter and spotlight models propose different mechanisms for attention o Consider examining a particular flower in a field of grass o Spotlight model suggests that attention would enhance the processing of the single flower relative to the grass o Filter models suggest that attention helps us to ignore the grass and allows for flower to continue on for further processing  The first filter model of attention was proposed by Donald Broadbent in 1958 o Often described as an early-selection theory because it filters information out relatively early and before it can be analyzed semantically 6 o He was keenly interested in practical problems such as the challenges faced by air traffic control operators receiving multiple channels of communication simultaneously o Broadbent used data from behavioural experiments to infer the functional stages of cognitive processing o According to his model, the attention filter selects important information on the basis of physical characteristics and allows that information to continue on for further processing o Information that does not pass through the early physical filter was assumed to be completely eliminated and unavailable for deeper analysis for meaning and semantic importance  Dichotic listening paradigm o Broadbent extended Cherry’s work using this paradigm o If you were a subject in a typical experiment, you would put on headphones and listen to a different message directed into each ear o Your job is to shadow the message in the attended ear by repeating back the message o If you were asked questions concer
More Less

Related notes for PSYCH 1X03

Log In


Don't have an account?

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.