Chapter 4- Attention Flashcards
Attention
The ability to focus on specific stimuli or locations.
Selective attention
Attending to one thing while ignoring others
Distraction
One stimulus interfering with the processing of another stimulus
Divided attention
Paying attention to more than one thing at a time
Attentional capture
A rapid shifting of attention usually caused by a stimulus such as a loud noise, bright light, or sudden movement.
Visual scanning
The movement of eyes from one location or object to another.
Cherry attention study
Cherry studied attention and used a technique called dichotic listening, where different stimuli were presented to the left and right ears using headphones. The participants focused on the message going to one ear and then repeated it out loud. The process of repeating the words is called shadowing. Participants could easily shadow the stimuli in one ear. They could report whether the voice in the unattended message was male or female, but not what they’d said. Broadbent’s filter model of attention was designed to explain the results of this experiment.
Cocktail party effect
The ability to focus on one stimulus while filtering out other stimuli. Even in noisy environments, people are able to focus on one conversation they’re having.
4 stages of Broadbent’s filter model of attention
- Sensory memory
- Filter
- Detector
- The output from the detector goes to short term memory
Broadbent’s filter model of attention
Broadbent’s model of attention was designed to explain how it’s possible to focus on one message and why information isn’t taken in from the other message. This model is called an early selection model since irrelevant information is eliminated by the filter early in this process before it can be analyzed. It filters based on the physical properties of the message rather than its content. It also provided testable predictions about selective attention, which lead to further research. Treats attention as a bottleneck.
Sensory memory
Holds all of the incoming information for a fraction of a second and then transfers all of it to the filter.
Filter
The filter identifies the message that’s being attended to based on its physical characteristics. These include the speech’s tone, pitch, speed of talking, and accent. Only the attended message will pass through to the next stage.
Detector
The detector processes information from the attended message to determine higher level characteristics, like the meaning of the message. The detector processes everything that passes through it, since irrelevant stuff was already filtered out in the filter stage.
In Broadbent’s model, what happens to output from the detector?
The output from the detector goes to short term memory. Short term memory holds information for 10-15 seconds and can then transfer the information to long term memory.
Moray dichotic listening experiment
This was another early selection model. Participants were told to shadow the message presented to one ear. However, when the participant’s name was presented to the unattended ear, about one third of participants recognized it. This meant that the person’s name had not been filtered out, and that it had been analyzed enough to determine its meaning, in contrast to predictions. This is similar to when you still hear someone say your name in a noisy room.
The attenuator analyzes incoming messages in terms of (3)
- Its physical characteristics- pitch, speed, etc
- Its language- how the message groups into syllables or words
- Its meaning
How is Treisman’s attenuation model of attention different from Broadbent’s?
Information in the channel is selected similar to what Broadbent proposed, but in this model language and meaning can also be used to separate messages.
Treisman’s attenuation model of attention
Treisman proposed that the analysis of the message proceeds only as far as is necessary to identify the attended message. For example, analysis at the physical level of each message could be used to separate them if there’s one male and one female speaker. However, meaning might be necessary to separate the messages if the voices sound similar. This is a late selection model.
Stages of Treisman’s attenuation model of attention
In this model, the attended and unattended messages are identified first. Then both messages pass through the attenuator, but only the unattended message is attenuated (weakened). At least some of the unattended message gets through, so the model is called the leaky filter model. The message is then analyzed by the dictionary unit- it contains words, stored in memory, and each of which has a threshold for being activated.
According to Treisman’s attenuation model of attention, which words have low thresholds?
Words that are common or important, like the participants’ name, have low thresholds. These words can be activated even with a weak signal, like when it’s spoken softly, unattended, or obscured by other words.
McKay study
Participants listened to ambiguous sentences, such as “they threw stones at the bank”- bank can have two meanings. In the unattended ear, words like “river” or “money” were played as biasing words. The biasing words influenced whether participants believed the ambiguous sentence had been about a river or about a financial institution.
Therefore, the biasing words must have been processed enough that the meaning was registered, even though participants were unaware that they had heard it.
Late selection models of attention
McKay’s research led to the proposal of late selection models of attention- proposed that most of the incoming information is processed to the level of meaning before the message to be further processed is selected. In a true late selection model all messages receive full acoustic AND semantic analysis. Selection takes place after ALL messages have been fully analyzed
Are early or late selection models of attention more accurate?
There is no one answer to the “early-late” controversy. Early selection and late selection are demonstrated in different situations depending on the task and the type of stimuli.
Which 2 factors must be considered when asking people to ignore distracting stimuli?
Processing capacity and perceptual load
Processing capacity
Refers to the amount of information people can handle and sets a limit on their ability to process incoming information.
Perceptual load
Related to the difficulty of a task. Low load tasks are generally easy, well practiced tasks that have a low perceptual load. High load tasks use up more of an individual’s processing ability
Load theory of attention (Lavie)
You are less likely to be distracted when participating in a high load task. With a low load task, there is still processing capacity left. Therefore, resources are still available to process the task irrelevant stimulus, and the response time slows down. With a high load task, there are no resources left to process irrelevant stimuli.
Lavie study
Lavie’s study asked participants to press a key if they saw an X or N on a screen. This was easy if the target letter was surrounded by other letters that were all the same, but more difficult if it was surrounded by different letters. Including an unrelated stimulus, like a cartoon character, increases the reaction times more for the easy task than it does for the hard task.
Other than a low perceptual load, what other factor could make you easily distracted?
It also depends how powerful the irrelevant stimulus is. If the fire alarm went off, a person would probably be distracted regardless of the load of their task.
Stroop effect
Difficulty naming the colors of the words. This occurs because the names of the words cause a competing response and therefore slow responding to the target (naming the color of ink). The task irrelevant stimuli (reading the actual words) is strong in this situation. Reading is an automatic response that is difficult to ignore.
Why do you need to look at things directly to have detailed vision?
Due to the way the retina is constructed, objects in central vision fall on a small area (the fovea) which has better detail vision than the peripheral retina.
Fixation
Fixing your eyes on a specific object
Saccadic eye movement
A rapid, jerky movement from one fixation to the next. Even when you aren’t searching for anything, your eyes still move 3 times per second.
Overt attention
Shifting attention from one place to another by moving the eyes
Stimulus salience
The physical properties of the stimulus, like color, contrast, or movement. Determining how salience influences the way we scan a scene typically involves analyzing characteristics like color, orientation, and intensity at each location in the scene and then combining these values to make a saliency map of the scene.
Is stimulus salience a bottom up or top down process?
Using stimulus salience for attention is a bottom up process because it depends on the patterns of color and contrast in a stimulus. You are responding to the physical property of the stimulus rather than its meaning.
High salience
An object has higher salience if it sticks out while looking at a scene. An individual’s first few fixations are usually on high salience areas. After a few fixations, scanning begins to be influenced by top down processes.
How do cognitive factors influence scanning?
There are variations in how people scan scenes- everyone might not scan a salient feature first. Scanning is also influenced by a person’s preferences, making it a top down process.