Attention. Concentrating and focusing of mental effort that is:

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1 What is attention? Concentrating and focusing of mental effort that is: Page 1 o Selective--focus on some things while excluding others o Divisible--able to focus on more than one thing at the same time (but at a cost) o Shiftable--able to change focus Selective How well can we select one focus and block out others? Under what circumstances is it under conscious control? Are there costs associated with ignoring? Dichotic listening (shadowing) Usually recall very little from unattended channel o remember nothing of content o do not notice a language change o do notice if becomes series of beeps Early Selection Repeat attended channel quite accurately Do not notice if message on unattended channel o changes from English to Russian o changes speakers Hear name only about 30% of time

2 as a filter with a bottleneck Page 2 Predictions of the model Operates solely on the physical characteristics (voice, location, intensity) not on meaning. Filtered materials on the unattended channels will be lost. Limited capacity--only a certain number of things can get through into consciousness. Cocktail Party Effect Seem to hear important information (like your name) even in situations in which you are supposedly filtering out irrelevant info. Treisman s attenuation model Instead of completely filtering out all unattended info, it gets through just at a lower intensity (it is attenuated).

3 Page 3 Important messages (like your name, fire alarms) are set to a lower threshold of awareness. However, there is evidence that low-priority messages get through. Often follow message from attended channel to unattended channel Shows extracting even low-priority information More Evidence Experiment: o Attended ear: They were throwing stones at the bank. o Unattended ear: Money o Test: Yes/no: They were throwing stones at the shore. o More likely to remember the sentence when one disambiguating word was in the unattended channel. Late selection theory All information is processed for meaning but only one response can be made. Difficulty in dealing with the finding that there is little conscious knowledge of unattended channel. Maybe a different perspective is needed Cocktail party effect revisited o Only about 1/3 of subjects notice their own name. o Look at individual differences in working memory capacity.

4 Page 4 Capacity theories Yerkes-Dodson Law

5 Circadian Rhythms Interim summary Temperature and Visual Search Temperature and Memory Page 5 is selective and certain individuals seem to be better at selecting than others. Most of the shadowing results can be explained by an individual differences approach in which individuals have varying capacity to process/ignore unwanted info. This capacity can change over time and circumstances (such as arousal). Divisible If there is a pool of resources, one should be able to do more than one thing at a time up to a limit. Dual task methodology Measure performance on each task by itself Measure performance on each task when done concurrently The difference between those is the cost of doing two things at once. Is there only one resource pool? Is there always a cost to doing two tasks? Selective Interference Brooks (1968) o Task 1: Hear a sentence

6 Page 6 Respond yes or no to indicate if a word is a noun o Task 2: Imagine Respond yes or no to indicate if an angle is greater than 100 o Selective Interference o Task 3: Say response o Task 4: Point response Multiple Resources o involves different resources o Verbal resource for both speaking and processing o Spatial resource for both angle judgment and pointing Problem: How many resources? As many as the data need explain everything, predict nothing Shiftability of attention Controlled v. Obligatory o Controlled: Spatial Cueing of Posner et al. (1980) press a key as fast as possible when a target is detected Fixation Neutral Cue Valid Cue

7 Invalid Cue Results Neutral: ~300 ms o baseline performance (control condition) Valid: ~275 ms o ~25 ms advantage of have attention waiting Invalid: ~335 ms o ~35 ms disadvantage of having to move attention Page 7 Unilateral Neglect An extensive lesion of the right hemisphere including damage to the parietal lobe o Ignore the affected half of space o Conversations initiated by someone to the left of the patient may be ignored o Only food located on right side of plate will be eaten o The left half of the face may not be shaved. Spatial cueing in neglect patients Show normal cuing effects for the side opposite their lesion if the cue was valid. However, when a cue went to the same side as their lesion and the cue was invalid they didn t detect the target. Implies that they can shift attention but cannot disengage it.

8 Page 8 and Automaticity Automatic take few or no attentional resources occurs without intention must run to completion not open to awareness parallel processing Reading Non-automatic requires attentional resources cannot occur without intent can be interrupted open to awareness serial processing Tying shoe laces Parallel v. Serial processing Parallel Multiple processes occurring at once. No deficit in either process when the other is occurring Serial processing One process at a time. Each process must finish before the next gets started. Deficit shown when more than one process occurs

9 Practice helps move from serial to parallel Reading Arithmetic Driving a car Page 9 Applications Learning to read/do math Human factors building design Smoking relapse Expertise of any kind Stroop Effect Say name of color out loud as fast as possible (Stroop, 1935) Automatic process of reading interferes with non-automatic process of color naming Developing Automaticity Practice, practice, practice. If the stimulus doesn t change much in different contexts, can develop automatic processing. If it is variable, can t automatize.

10 and automaticity in perception Feature integration theory Two stages Page 10 o Pre-attentive processing--based on basic features of the stimulus (color, orientation, size), no attention necessary, doesn t take any resources, parallel processing. o Conjunctive processing--based on a conjunction of features, attention necessary, takes resources, serial processing. Triesman s glue is the glue that binds the basic features together into objects. Visual Search Simple feature search: target s features do not overlap with distractors features o Pop-out o Doesn t require attention Conjunction search: target s features do overlap with distractors features o No Pop-out o Requires attention

11 Visual search CogLab homework IVs: o feature v. conjunction search o Yes or No response o number of distractors DV: o response time Page 11 Feature integration theory In the feature search condition, no attention was needed, parallel processing, so the responses are fast, automatic and aren t affected by how many distractors. In conjunction, attention needed, serial processing, so the responses are slow and are affected by the number of distractors. Illusory conjunctions X A * M R On some trials report seeing red R or blue X Real-world example: Computer solitaire needed to glue together features Change Blindness Don t attend to all aspects of a scene equally. Top-down processes fill in

12 summary is Concentrating and focusing of mental effort that selective, divisible, shiftable Original conceptions of attention was that of a filter with a bottleneck (early, late selection) Later conceptions included the idea of a pool of resources (single, multiple) Certain brain areas are associated with the ability to move attention Page 12 Through practice, some processes can become automatic in that they require no attention and occur in parallel summary Feature integration theory demonstrates the multiple steps in attending to a visual scene Change in the visual scene is often not noticed (top-down processes are used extensively)