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Attention
Understand the model, recognise it in a stem, separate the look-alikes, then apply it.
Start with the mental model
The same complaint, 'poor concentration', can come from several different attentional failures. Someone may focus well in silence but collapse with distraction, or stay focused for two minutes but not twenty. The exam move is to ask what the task demands: filtering, sustaining, switching, or doing two things at once.
Visual explanationUse the diagram to rebuild the concept from memory.
01Core model
Selective attention filters irrelevant stimuli while keeping the target in focus; the Stroop task adds interference because the automatic reading response must be inhibited. Sustained attention, or vigilance, maintains performance over time and may show a vigilance decrement as misses increase. Alternating attention shifts flexibly between tasks with different rules. Divided attention handles two task streams at the same time and is usually more demanding than alternating attention. Focused attention is the simpler ability to respond to a specific stimulus. These attention systems depend heavily on frontal, parietal, and subcortical networks, so bedside errors often overlap with executive dysfunction.
02Recognise it in an SBA
• A cognitive model separates attention into three networks: alerting to a warning, orienting to a location, and executive control of conflict. Whose model is this?
• During a video task counting basketball passes, many viewers fail to notice a person in a gorilla suit walking through. This failure illustrates what?
03Separate the look-alikes
| Selective vs sustained attention | selective attention filters distractors, whereas sustained attention maintains focus over time. |
|---|---|
| Alternating vs divided attention | alternating attention switches between tasks, whereas divided attention handles simultaneous demands. |
| Stroop vs continuous performance test | Stroop tests interference and selective control, whereas continuous performance tests vigilance. |
| Attention vs memory | failed attention can prevent encoding, whereas true memory impairment fails even after adequate attention at learning. |
How the exam thinksRead the question the way the examiner wrote it.
What people get wrong here
• Broadbent's filter model explains selective attention through an early, all-or-nothing sensory filter, not three networks.
• Kahneman's capacityA person's ability to understand, weigh up, and use relevant information to make a specific decision.Read more → model treats attention as one limited pool of resources, not three separable networks.
• Divided attention deficit describes impaired performance when sharing attention between two simultaneous tasks.
• Sensory adaptation is reduced responsiveness to a constant unchanging stimulus over time, a different phenomenon.
• Selective attention filtering describes prioritising one input over others, not a total failure to perceive an item.
Deep diveStart from scratch, the full, beginner-friendly explanation.
**Name the attentional demand before naming the deficit.** Filtering distraction is selective attention; maintaining performance is sustained attention; switching rules is alternating attention; simultaneous dual-tasking is divided attention.
For example, a patient who reads accurately in a quiet room but cannot follow one speaker in a busy ward has a selective-attention problem. A patient who starts a continuous performance test well but misses more targets over twenty minutes has a sustained-attention problem. A patient who can do each task alone but fails when asked to monitor both together has a divided-attention problem.
Clinically, this matters because poor concentration is not a diagnosis. Depression, delirium, traumatic brain injury, attention deficit hyperactivity disorder, dementia, and anxiety can all impair attention, but the pattern of failure helps decide which domains to test next.
01Types SELECTIVE attention focusing
Types: SELECTIVE attention, focusing on one stream and filtering distractors (cocktail-party effect; that one's own name still breaks through supports a late/attenuation filter, Treisman, rather than Broadbent's early all-or-none filter).
02Stroop task taxes selective
The Stroop task taxes selective attention plus inhibition of the prepotent reading response.
03SUSTAINED attention/vigilance maintaining focus
SUSTAINED attention/vigilance, maintaining focus over time (Continuous Performance Test; shows a vigilance decrement).
04DIVIDED attention two tasks
DIVIDED attention, two tasks at once.
05Trap 'alternating attention is
Trap: 'alternating attention is the highest level' is false.
06Selective attention deficits and
Selective attention deficits and the Stroop effect localise to frontal-executive systems.
Worked application
Worked application: A cognitive model separates attention into three networks: alerting to a warning, orienting to a location, and executive control of conflict. Whose model is this? The best answer is “Posner's attention network model.” because Posner's attention network model separates alerting, orienting and executive control as distinct, interacting attentional systems.
The story in picturesPredict each next frame before you reveal it.
04Question-solving strategy
• Name the learning, social or research principle being tested before reading the options.
• Identify the antecedent, behaviour, consequence or cognitive process in the vignette.
• Compare the direction of effect with the nearest competing principle.
• Apply the same rule to a new example to confirm that the answer transfers.