PSYC 105 - CH 5: Attention

Attention

Attention

process of concentrating on specific features of the environment or on certain thoughts or activities

Selective attention

focus on one object/idea/etc., excludes others

• we do not attend to a large fraction of the information in the environment

• filtering out some information and promoting other information for further processing

Divided attention

the processes used to focus on more than one source or task at once

Dichotic listening

one message is presented to the left ear and another to the right ear

• participant “shadows” one message to ensure they are attending to that message

• results show it’s easy to report the shadowed message

• participants could not report the content of the message in the unattended ear

  • knew that there was a message (vs. music or silence)

  • knew the gender of the speaker, tone of voice (high/low, soft/loud)

• the unattended ear is being processed at some level

  • change of tone or gender is noticed

Early selection model

Broadbent’s filter model

• filters message before incoming information is analyzed for meaning

Sensory

• Holds all incoming information for a fraction of a second

• Transfers all information to the next stage

Filter

• identifies attended message based on physical characteristics

• Only attended message is passed on to the next stage

Detector

• Processes all information to determine higher-level characteristics of the message (i.e. - meaning of the message)

Short-term memory

• Receives output of detector

• Holds information for 10-15 seconds and may transfer it to long-term memory

Does NOT explain

• why the participant’s name gets through

  • cocktail party effect

• effects of practice on detecting information in the unattended ear

  • you can be trained to detect in unattended ear

  • based on meaning of message

• Participants can shadow → meaningful messages that switch from one ear to another

Intermediate-selection model

Treisman’s Attenuation Theory

• attended message is separated from unattended message early in the information-processing system (before meaning processing)

• Only important unattended info is fully processed for meaning and brought to conscious awareness

Attenuator

• analyzes incoming message in terms of physical characteristics, language, and meaning

• Attended message is let through the attenuator at full strength, unattended message is let through at a much weaker strength

Dictionary unit

• contains words, each of which have thresholds for being activated

  • words that are common or important have low thresholds

  • uncommon words have high thresholds

Late selection model

• selection of stimuli for final processing does not occur until after ALL information has been analyzed (unconsciously) for meaning → selection process happens after

• the meaning of the biasing word significantly affected participants’ choice

• yet participants were unaware of the presentation of the biasing words

Inattentional blindness

a stimulus that is not attended is not perceived, even though a person might be looking directly at it

• sometimes effects of attention are so strong that we fail to see stimuli that are directly in front of our eyes

• no warning leads to failure to detect change in fixation dot

• unconscious perception can still occur in the absence of attention

  • no conscious perception without attention

Change blindness

if shown two versions of a picture, differences between them are not immediately apparent

• Task to identify differences requires concentrated attention and search

• as the task difficulty inc, participants were less likely to notice the fight (esp @ night)

• attention is necessary for (conscious) perception

Task load

how much of a person’s cognitive resources are used to accomplish a task

Flanker-compatibility task

• can participants focus their attention on detecting the target so that the identity of the distractor will not affect their performance

• Results: reaction time is longer for incompatible distractors

  • since this a low-load task, participants still had cognitive resources available to process additional (although irrelevant) information

• incompatible distractor increases reaction time ONLY for low-load, not high-load condition

High-load

• participants use all resources for task

• no resources left process the extra distractor

High-load

uses almost all resources; no resources left over for other tasks

• ____ experiments support early selection

  • complex stimuli involve more effort, no resources left to process unattended information

Low-load

uses few resources; plenty of resources left over for other tasks

• ____ experiments support late selection

  • less complex stimuli take less effort, so even the unattended information is processes to an extent

Spatial attention

attention can be “primed” to a location without moving the eyes

• participants respond faster to light at an expected action than at an unexpected location

location-based

attention being directed to one particular spatial location

object-based

attention being directed to one particular object

• damage to the right parietal lobe

• cannot attend to the left side of space

Unilateral neglect syndrome

• damage to the right parietal lobe

• cannot attend to the left side of space

• it is not that they can’t see they just don’t notice unless told

• Even when drawing with reference, they are still likely to miss left details

• believed that they drew the whole image completely

• “the eyes are slaves to attention”

• symptoms support the idea of location-based attention

  • some experiments suggest that the deficit is also object-based

• Once their attentional system is locked onto the target, they don’t lose it when it is moved to their left field of vision

Balint’s syndrome

patients can only focus on one “object” at a time

• grouping objects into one helps → ie: connecting red dots with green dots with a single line helps see them as one object and therefore see both red and green

Resource specialization

doing two tasks at once is easier if the two tasks are relatively different (verbal + spatial is easier than verbal + verbal)

• task-specific vs. task-general cog resources

• our attention can be lessened when doing two things at once (ie: driving and talking, talking and walking)

Central executive theories

executive control

• involved in working memory

• keeps desired goal in mind

• serves to inhibit automatic responses

Prefrontal cortex damage

PFC is particularly important to executive control

• patients with PFC damage show preservation errors as well as goal neglect

Practice

enables people to simultaneously do two things that were difficult at first

Schneider and Shiffrin (1977)

• consistent mapping → target would always be numbers, and distractors would be always letters

  • with _______, were able to do the task automatically, without consciously working to divide attention

• Automatic processing occurs without intention and only uses some of a person’s cognitive resources → more susceptible to distractors

• Varied mapping condition: rules changed from trail to trail

  • over time, participants never achieved automatic processing

  • had to engage in controlled processing due to changes in rules