Attention - What happens to information we ignore?

Early Selection Theory

Early Selection Theory

Suggests attention filters information early in processing just based on physical characteristics.

Late Selection Theory

Suggests that the brain processes all information (physical characteristics and meaning of stimuli) before filtering

The Cocktail Party Effect

Phenomenon proposed by Colin Cherry where we are able to focus on one conversation while filtering out other conversations in a crowded room.

Dichotic Listening Task

2 different messages given to separate ears. Participants asked to attend to only one. Participants can shadow (focus on) the attended message easily. However for the unattended message participants could only report physical characteristics about it.

Broadbent’s Filter Theory

“Early Selection” model. Filtering occurs before incoming stimuli are analysed to the semantic level.

Problems with Early Selection Models of Attention

• Moray (1959): Subjects heard their name in the unattended stream

• Treisman (1960): Bilinguals influenced by the unattended stream if it is in second language.

• Gray & Weddeburn (1960)

Treisman’s Attenuation Model

An “Early Selection Theory”. Builds on Broadbent’s filter theory. Suggests unattended messages are attenuated (reduced) rather than lost. So it suggests words need to meet a certain threshold of signal strength to be detected (e.g. own name = strong).

Late Selection Models of Attention

Argues everything is processed to the stage of semantic (meaning) analysis. Suggests selection takes place at a higher level of processing and is based on analysis of which input is most important.

What do Late Selection Models explain?

• Response competition interference (Eriksen & Eriksen 1974)

• Negative Priming

• Findings from Tipper & Driver (1988): Task: Categorise red stimuli, ignore green.
  Result: Responses to word slowed when preceded by semantically related IGNORED picture.

• Why ignored stimuli is semantically categorised and inhibited

MacKay (1973)

Lavie’s Load Theory

Suggests both early and late selection is possible. Stage of selection depends on availability of perceptual capacity. Suggests perceptual capacity is limited and tasks with a high perceptual load exhaust capacity. Whereas tasks with low perceptual load leave spare capacity.

Evidence supporting Load Theory

• Behavioural Measures of Distraction – Response competition effects found under low load. This is reduced/eliminated under high loads. Similar effects found for irrelevant distractors. (effects for low load but not high)

• Inattentional Blindness: Cartwright, Finch & Lavie (2006). Unexpected stimulus on perceptual load task. Effects for low load not high load.

• Neuroimaging Evidence:

  • Schwartz (2005): Ignore background and either, low load: detect red cross, high load: Detect correct colour & conjunction (orientation)

  • Bishop et al (2007): High perceptual load reduces amygdala response to fearful faces.

Implications for individual Differences

Efficiency of selective attention depends on perceptual capacity. (high capacity needs high load to avoid distraction)

What are differences in attentional capacity associated with?

• Autism

• Age

• Video Game Experience (Green & Bavelier, 2003: VG players remained distracted under high load)