20130410 Regular meeting

1. 20130410Regular meeting Ting-Yun Chang

2. Attention is spontaneously biased toward regularities Zhao, J., Al-Aidroos, N., & Turk-Browne, N. B. (2013). Psychological Science. Advance online publication. doi: 10.1177/0956797612460407.

3. Take-Home Message Regularities, even task-irrelevant, influence the allocation ofspatial and feature attention.

4. The mind extracts regularities in the environment to interact with the environment more efficientlyvia statistical learning. • Conjecture: • Structured sources of information receive attentional priority in the context of other, noisier sources of information. • Attention is biased by regularities even when they do not provide information that is helpful for performance.

5. Whether visual search is facilitated at a spatial locationcontaining temporal regularities Experiment 1

6. Method (1 for left; 0 for right) • 25 participants • Visual search task • Structured/Random shape stream in different locations • Each shape repeated 50 times

7. Method (cont’) • Test for sensitivity to regularities • 2AFC test • Triplet versus Foil • 3 triplets X 3 foils X 2 repetitions • Debriefing • Had you noticed any regularities? Which location? • Did you use a strategy of attending to a specific location? Which location? (1000 ms pause)

8. Results • Statistical learning occurred • Triplets were chosen over foils on 54% • Target-discrimination RTs: • Target in structured < Target in random • Debriefing: • 7 participants reported noticing regularities • Only 1 of them correctly identified which location contained regularities • Attention is biased toward locations of regularities.

9. Whether temporal regularities among shapes in a color enhance attentional capture by that color Experiment 2

10. Method (1 for left; 0 for right) • 20 new participants • Visual search task • Structured/Random shape stream in different colors • Each shape repeated 40 times • 2AFC test • Debriefing

11. Results • Statistical learning occurred • Triplets were chosen over foils on 61.1% • Target-discrimination RTs: • Target in structured < Target in random • Main effect in singleton type and color • Debriefing: • 6 participants reported noticing regularities • Only 2 of them correctly identified which location contained regularities • Attention is biased toward colors of regularities. 2 (singleton type: target/distractor) X 2 (singleton color: structure/random) ANOVA

12. Whether temporal regularities in a feature dimension enhance capture by singleton in that feature dimension Experiment 3

13. Method • 30 new participants • Structured/Random line stream in different dimensions • Each line repeated 60 times • 2AFC test and Debriefing (Between group)

14. Results Greater attentional capture for singleton in the structured dimension • Statistical learning occurred • Triplets were chosen over foils on 66.3% (color) and 72.6% (orientation) • Debriefing: (for both group) • 6 participants reported noticing regularities • Only 2 of them correctly identified which location contained regularities • Attention is biased toward feature dimension that contains regularities. 2 (group: color/orientation) X 2 (singleton type: target/distractor) X 2 (singleton dimension: color/orientation) ANOVA

15. Main effect in singleton dimension Color group>Orientation group C O O C Greater attentional capture for singleton in the structured dimension Main effect in singleton type C D O O D C T T

16. General Discussion • Across three experiments, locations and features embedded in temporal regularities received attentional priority in visual search. • Interpretation. There is an implicit attentional bias for regularities during statistical learning • Randomness: • When attempts to learn in random streams failed, attention may have redirected to other streams, eventually settling on the structured stream. • Structure: • Regularities matched priority experience attracted attention • Input matches prior experience incidentally cue memory retrieval and engage attention network

17. Thank You.