Attenuation theory
Attenuation theory, also known as Treisman’s attenuation model, is a theory of selective attention proposed by psychologist Anne Treisman that explains how the mind processes sensory input by weakening (attenuating) unattended stimuli rather than fully blocking them. It suggests that all incoming information is analyzed to some extent, but irrelevant inputs are reduced in strength, allowing only those with sufficient significance after attenuation to reach conscious awareness through a layered process. Developed as a revision of Donald Broadbent’s filter model—which proposed a strict barrier to unattended stimuli—Treisman’s theory addressed cases where ignored information still broke through, adding nuance to how attention operates and influencing later research on the subject.
In psychology, “attenuation” primarily refers to Anne Treisman’s Attenuation Model of Selective Attention, which proposes that information not attended to is weakened or “attenuated” rather than completely blocked, allowing personally significant stimuli (like your name) to still be recognized. A related concept, sensory attenuation, describes the reduced experience of self-generated sensations compared to externally generated ones, a phenomenon thought to involve internal models of action.
Attenuating Unattended Information
Treisman’s Attenuation Model: This model modifies Donald Broadbent’s original Filter Model, which suggested that unattended information was entirely blocked. Treisman proposed that the brain acts as an attenuator, “turning down the volume” on unattended information.
Threshold Effect: Information that is more important or personally relevant, such as your own name or a warning, has a lower “threshold” for recognition. This means it requires less activation to reach conscious awareness.
“Dictionary” Unit: Treisman suggested a “dictionary” within the model where words have different thresholds for activation. Words with low thresholds, like common or personally significant ones, are more likely to be recognized even when attention is directed elsewhere.
Cocktail Party Effect: This model helps explain phenomena like the cocktail party effect, where you can still hear your name called out in a noisy, crowded room, even if you are engaged in a different conversation.
Sensory Attenuation
Self vs. External Stimuli: Sensory attenuation is the reduced perception or intensity of stimuli that you generate yourself, compared to identical stimuli generated by an external source.
“Efference Copy” and Prediction: This effect is thought to involve internal “forward models” in the brain, which use a copy of your motor commands (an efference copy) to predict the sensory consequences of your actions.
Predictive Suppression: By predicting the sensory results of your actions, the brain can suppress or “attenuate” the actual sensory input, leading to a weaker subjective experience of self-generated sensations.
Example: A touch to your own arm feels less intense than the same touch from an external source because your brain predicts and attenuates the sensory feedback from your own movement.