1 Psychology and human development1.1 Sensation and perception
1.1.6 Information processing and attention
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Written by Resident Doctor Committee · Published
Attention in information processing
Attention is the selective gate that admits brief, high-capacity sensory input into working memory.
Attention is separate from consolidation, the later step that stores material in long-term memory, so poor recall can reflect failed selection, encoding or retention.
Automatic and controlled processing
Feature | Automatic | Controlled |
|---|---|---|
Trigger | Stimulus | Intention |
Capacity | Low demand | Competes for resources |
Style | Fast, rigid | Slow, flexible |
Origin | Repeated practice | Novel tasks |
Stroop interference is the slowing and word-reading errors that occur when an automatic response (reading the word) clashes with a deliberate one (naming the ink colour).
Stroop interference marks failed inhibitory control and is worse after frontal injury.
Types of attention
Type | What it is | Example or test |
|---|---|---|
Selective | Choosing one source among several | Dichotic listening, Stroop |
Focused (orienting) | Rapid, automatic, stimulus-driven capture by a sudden salient event | |
Sustained (vigilance) | Keeping steady processing on one task over a prolonged period | Continuous performance test |
Divided | Doing two demanding tasks at once from one limited pool of capacity, so performance suffers | Driving while holding a conversation |
Alternating | Switching between tasks | Trail Making B |
Focused attention can stay intact while effortful forms of attention are impaired.
Mackworth first measured the vigilance decrement in radar operators watching a clock pointer: detection falls after about 30 minutes.
The cocktail party effect
The cocktail party effect, named by Colin Cherry in 1953, is selective auditory attention to one voice among several equally loud simultaneous conversations.
Voice and location cues help people select, and the ignored streams are still partly processed.
Dichotic listening is the laboratory method: a different message enters each ear and the person repeats one aloud.
People report physical features of the unattended voice but little of its meaning.
Models of selective attention
Model | Where selection occurs | Main claim |
|---|---|---|
Broadbent (1958), early filter | Before meaning is analysed | A single limited-capacity channel selects on physical features such as ear or pitch and blocks unattended input all-or-none |
Treisman, attenuation | Before full analysis, but leaky | Unattended input is weakened, not blocked |
Deutsch and Deutsch (1963), late selection | At response or memory | Every input is fully analysed for meaning |
Johnston and Heinz | Movable | The filter can sit early or late |
Kahneman | No filter | A shared capacity limit governs attention |
Moray showed that people notice their own name in the unattended channel, which challenged Broadbent and prompted the attenuation model.
In Treisman's model, attenuated input is matched against a store of words, the dictionary unit, whose recognition thresholds vary.
Low-threshold words, such as one's own name or salient words, break through even when attenuated.
Broadbent blocks unattended input completely, Treisman only turns it down, and Deutsch and Deutsch let it through fully analysed.
Clinical patterns
Inattention is the core, defining cognitive deficit of delirium and a required diagnostic criterion.
In anxiety, attentional bias to threat follows a vigilance-avoidance time course on eye-tracking: faster early orienting to threat, then gaze directed away.
The avoidance phase blocks habituation and so maintains fear.
In schizophrenia, selective and sustained attention are impaired, and P50 gating and prepulse inhibition are reduced.
In ADHD, sustained attention and inhibition are poor, with childhood onset.
In depression, processing slows and vigilance is poor, and attention may recover as mood improves.