Key Concepts in Theories of Attention

Why This Matters

Understanding theories of attention is essential for grasping how perception actually works—because you don't perceive everything in your environment, only what your brain selects and processes. These theories explain the mechanisms behind selective attention, divided attention, visual search, and resource allocation, all of which appear frequently on exams. You're being tested on your ability to distinguish between early vs. late selection models, understand capacity limitations, and explain how attention binds features into coherent perceptions.

Don't just memorize the names of these theories—know what problem each one solves and where it fits in the broader debate about when and how filtering occurs. The real exam payoff comes from understanding how these theories build on, modify, or challenge each other. When you can explain why Treisman modified Broadbent, or how Load Theory reconciles the early vs. late selection debate, you're thinking like a psychologist.

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Early Selection Theories: Filtering Before Meaning

These theories propose that attention acts as a filter before semantic processing occurs. The key question they address: how does the brain decide what information gets fully processed when sensory input exceeds our capacity?

Broadbent's Filter Theory

• Early filtering based on physical characteristics—information is selected based on features like pitch, loudness, or location before meaning is extracted
• Single-channel bottleneck creates selective attention by allowing only one stream of information through at a time
• Unattended information is completely blocked, which explains why we miss messages in the unattended ear during dichotic listening tasks

Treisman's Attenuation Theory

• Attenuated rather than blocked—unattended information is turned down like a volume dial, not completely filtered out
• Dictionary unit with variable thresholds explains why you hear your name in a crowded room (the cocktail party effect)
• Modified early selection maintains Broadbent's basic structure while accounting for breakthrough of meaningful stimuli

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Late Selection Theories: Processing Everything First

These models argue that all incoming information receives full semantic analysis before attention selects what reaches consciousness. Selection happens after meaning is extracted, not before.

Deutsch and Deutsch's Late Selection Theory

• Full semantic processing of all inputs—every stimulus is analyzed for meaning before the attentional filter kicks in
• Selection based on relevance and importance rather than physical characteristics, occurring after comprehension
• Emphasizes meaning over sensation, suggesting the brain does more unconscious processing than early selection models assume

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Capacity and Resource Models: Attention as Energy

Rather than focusing on when selection occurs, these theories ask how much attention we have and how it gets distributed. They treat attention as a limited pool of mental energy or multiple specialized resources.

Kahneman's Capacity Model

• Attention as a flexible, limited resource that can be allocated across tasks based on current demands and arousal level
• Mental effort varies with task difficulty—harder tasks consume more of the available pool, leaving less for other processing
• Central capacity allocation is influenced by enduring dispositions, momentary intentions, and evaluation of task demands

Multiple Resource Theory

• Separate resource pools for different modalities—visual, auditory, verbal, and spatial tasks draw from distinct reservoirs
• Cross-modal multitasking is easier because tasks using different resources (e.g., listening while driving) interfere less than same-resource tasks
• Task compatibility determines interference, explaining why texting while driving (both visual) is harder than talking while driving

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Visual Attention and Search: Finding What Matters

These theories explain how attention operates in visual perception—how we search scenes, combine features, and shift focus across space.

Feature Integration Theory

• Two-stage processing model—preattentive stage detects basic features automatically and in parallel; attentive stage requires focused attention to bind features together
• Solves the binding problem by explaining how separate feature detectors (color, shape, motion) combine into unified object perception
• Illusory conjunctions occur without attention—features can be incorrectly combined when attention is divided, proving binding requires focus

Spotlight Theory of Visual Attention

• Attention as a moveable spotlight that enhances processing of stimuli within its beam while leaving peripheral areas less processed
• Flexible in size and location—can narrow for detailed analysis or widen for broader monitoring
• Enhanced processing within the beam explains faster reaction times and better accuracy for attended locations

Guided Search Theory

• Combines bottom-up and top-down guidance—attention is directed by both stimulus salience (bright, moving objects) and your goals (looking for your keys)
• Parallel feature processing feeds serial search—basic features are detected simultaneously, then attention is guided to likely targets
• Prior knowledge shapes search efficiency, explaining why experts find targets faster in their domain of expertise

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Selective Attention and Competition: What Wins?

These theories address how attention handles competing stimuli and distractors—what determines which information gets processed and which gets suppressed?

Load Theory of Selective Attention

• Perceptual load determines distractor processing—high-load tasks exhaust capacity, leaving nothing for distractors; low-load tasks allow distractor intrusion
• Reconciles early vs. late selection debate by showing both can occur depending on task demands
• Practical implications for focus—if you're easily distracted, increase the perceptual demands of your primary task

Biased Competition Theory

• Stimuli compete for neural representation—multiple objects in the visual field suppress each other's neural responses
• Attention biases competition by enhancing the neural signal for relevant stimuli while inhibiting competitors
• Dynamic and context-dependent—what wins the competition shifts based on goals, salience, and task demands

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Quick Reference Table

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Self-Check Questions

1. Both Broadbent's Filter Theory and Treisman's Attenuation Theory propose early selection—what key modification did Treisman introduce, and what phenomenon does it explain?

2. How would you use Load Theory to reconcile the debate between early and late selection models? Under what conditions would each type of selection occur?

3. Compare Feature Integration Theory and Guided Search Theory: what do they share in their approach to visual attention, and how do their emphases differ?

4. If someone can easily listen to a podcast while cooking but struggles to text while driving, which theory best explains this difference, and why?

5. An FRQ asks you to explain why you might hear your name spoken across a noisy room even when you weren't listening to that conversation. Which theories are relevant, and how would you structure your response?