1. What is attention? What are the effects of paying attention?

2. 3 meanings of the word attention:
1. Selectivity: only aware of a subset of stimuli--selective attention.
2. Capacity Limitations: limited ability to handle different tasks or stimuli at once--divided attention.
3. Sustained mental effort: limited ability to engage in protracted thought, especially on the same subject--vigilance.
1. For instance, when you’re in a crowded room, and you are attempting to follow a single conversation amidst lots of others. Sitting in a movie theatre trying to ignore the person talking behind you...
2. E.g. when you are driving and carrying on a conversation simultaneously…or talking to your parents on the phone and watching television at the same time...when you are trying to simultaneously write notes and listen to the constant barrage of information the instructor spews out, while gauging the progress of a media services repair guy...
3. The task of a night watchman who must remain alert while monitoring the same empty video monitor for hours at a time. Or the task of a student trying to absorb 50 minutes worth of lecture material. This is usually the kind of attentional deficit that is associated with ADHD.
We’ll start by talking about selective attention...

3. Shadowing Experiments (Cherry,1953)
“dichotic listening”
Prose
Passage #1
Prose
Passage #2
Subjects were required to shadow the prose that they heard in one ear….to repeat back word for word what they were hearing. This was just away to ensure that they were paying attention to that particular message.
Cherry was interested to learn what the fate of the information in the unattended channel would be...

4. Shadowing Exps: Findings
Subject Tries to Comprehend Both:
1. Fails!
Subject Shadows One Ear:
2. Unable to report the contents of the unattended channel.
3. Improved performance with physical attributes of stimuli (e.g., pitch, loudness, location).
Subjects are not able to achieve comprehension of both messages.
2. Subjects are almost completely unaware of the material presented in the unattended channel.
Subjects failed to notice that the unattended message was in Czechoslovakian (4/30 got it)...
but some things ARE noticed: changes in pitch of the unattended message (or the gender of the speaker) are noticed, the complete cessation of the unattended message is noticed…

5. Questions we can ask about these attention effects:
1. Is it limited to verbal stimuli? (show video)
2.a. What aspect of the unattended information is filtered out?
2.b. Where in the stream of information processing does the filter occur?

6. Early Selection Model (Broadbent, 1958)
FILTER
input
detection
recognition
- The attentional filter lets through stimuli with certain physical features (e.g. pitch, location, size).
- Only information that passed the filter received further analysis (e.g. meaning, or shape).
- Consistent with ‘gorilla’ video
This theory was based on those results that suggested that the unattended information was almost completely unanalyzed…subjects could only report the most elementary features of the unattended messages.

7. “Mary had a little lamb”
Challenges to Early Selection Theory
Moray (1959)
“Mary
had a
little
lamb”
“...[John Smith]
you may stop now”
Result
w/o name: 6% notice
w/ name: 33% notice
We’ve already discussed how subjects are aware of certain basic information within the unattended channel (gender of speaker…presence of speaker). But it turns out there are other things they are aware of that pose a challenge for strict early selection models.
This experiment shows that the semantic content of the unattended message has a real effect. How could subjects recognize their names if they hadn’t been processing the unattended channel to the point of recognition?
“Mary had a little lamb”

8. Treisman (1960) jumping message expt.
example
attended ear: I SAW THE GIRL / song was WISHING
unattended ear: me that bird / WALKING in the street
Conclusion
Meaning of unattended message is processed.
Thus, selection is “later” than previously thought.
Let’s try a quick demonstration...

9. Read the sentence
in RED as fast as you can.

10. Let’s read an monster about attention!
Susan caught article fish using sandcrabs

11. The window meets in Washington Can Legislature about of fish
Here, the meaning of “Washington” is consistent with the attended sentence structure. This makes it more likely for people to notice and sometimes read this word from the unattended channel.
How does meaning penetrate if the filter is prior to recognition?

12. (Deutsch & Deutsch, Norman)
Late Selection Theory
(Deutsch & Deutsch, Norman)
FILTER
input
detection
recognition
Late selection theory was put forth in reaction to data that suggested that the meaning of the of materials in the unattended channels was important. If the meaning of materials in the unattended channel affected subjects’ experience of the unattended information, then recognition of the unattended stimuli must be occurring…
Stimulus input is analyzed to the point of recognition.
After that, only relevant information is remembered.

13. So…Is attentional selection early or late?
An intermediate position (Treisman, 1960):
Unattended messages are attenuated (partial blocking).
Unattended stimuli do not usually cause their detectors to reach threshold, unless the detector has been primed (e.g. repetition priming or frequency of occurrence might cause this).
By this account, unattended information has an influence when that information is particularly relevant, or frequent.
We have a body of evidence (like Cherry’s) that suggests that everything but the most basic low level features of the attended channel is blocked out…while other studies show effects of unattended information that seem to require analysis of meaning in that unattended channel. How can these results be reconciled?
Treisman’s account suggests that filtering can begin early, but isn’t all or none. The little bit of information that does make it through might be fully recognized when that information is primed by experience or some other source of top down activation.