Psychology 100:12 Chapter 5 Sensation & Perception Part V

Outline Pattern recognition Attention > Bottleneck theories > Capacity theories > Cells phones and driving Study Question: Why might a proponent of Kahneman’s attention theory feel that driving a car while talking on a cell phone is a bad idea?

Perception Feature detectors Perception – Visual Illusions, attempt II. >Fraser IllusionFraser Illusion >LinesLines >PerspectivePerspective >Stereokinetic objectStereokinetic object –Auditory Illusions > Never ending auditory staircase  Shepard Illusion Shepard Illusion

Perception Other evidence for feature theory: Stabilized retinal images. Physiological nystagmus Perception Feature detectors Perception

d a b c Problems with Feature theory –How features go together are as important as the features themselves. Perception Feature detectors Perception

Structural Theories –Like feature theories, except that they also consider the structure of the features (i.e., How they go together. –Biederman’s Theory of 3-d object recognition. >Geons: 3-D ‘volume’ features Perception Feature detectors Perception

-> Eliminating information about the relationship between geons should be detrimental to pattern recognition. E.g., Perception Feature detectors Perception

-> What are these objects? Recognition accuracy 70 %50 % 100 % Perception Feature detectors Perception

The word superiority effect Perception Feature detectors Perception

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Perception The word superiority effect D X X XX _ _ _ D W O R D X X XX _ _ _ D R U E D X X XX _ _ _ D -> It is easier to identify a letter in the context of a word than by itself. Perception Feature detectors Perception

The interactive - activation model: Bottom-up Perception Feature detectors Perception

Feature detectors Perception The interactive - activation model: Top-down

Pattern Recognition Hxw xbxux txix oxe, xhxcx hxs xvxrx oxhxr xextxr xixsxnx?Thxs oxe ix haxdex bexauxe exerx thxrd xetxer xs mxssxng.Herx evexy foxrth xettxr hxs bexn rexlacxd. This xentexce is xasy tx read xven txough xvery xifth xettex is goxe Perception

Dichotic listening § Shadowing Doughnuts TV Pork rinds Football Cheap meat Beer Work Dieting Romantic movies Literature Opera Ballet Doughnuts,TV, Pork rinds, Football, Cheap meat, Beer... Perception Feature detectors Attention

Attention Bottleneck theories: Early selection –The bottleneck metaphor >Cherry (1953): What do we perceive in the unattended ear?  Physical characteristics  Not meaning  Where’s the unattended message? >Broadbent’s all-or-nothing filter

Table Horse Chair Desk Paper House Tree Rock Homer Barn Street Table, horse, chair,.. Homer... Problems with the all-or-nothing filter –Moray’s (1959) experiment Attention

Treisman’s experiment I saw the girl song was wishing Hand me that bird jumping in the street I saw the girl jumping in the... Attention

Capacity theories of attention Different tasks require different amounts of mental effort § i.e., Automatic vs. Controlled processing e.g.1, Attentional resources and Driving e.g.2, Automaticity and word recognition The Stroop Effect Attention

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Capacity theories of attention Kahneman’s Model § Limited resources to allocate to different tasks § Spreading attention out over multiple tasks results in performance decrements e.g., Mowbray’s (1953) experiment - Trying to copy notes and listening to a lecture Attention

Resolving the locus of the bottleneck Johnston & Heinz’s (1978) multimode theory - Measured the amount of resources required to shadow using a dual task procedure. - Participants shadowed on either the basis of pitch (early) or semantic category (late) - Viewed a computer monitor and had to hit a button quickly whenever a dot appeared on the screen (detection). Results Attention No list 1 list 2 lists 2 lists (pitch) (semantic) Detection time310 ms 370 ms 433 ms 482 ms Shadowing errors n/a 1.4% 5.3% 20.5%

Johnston & Heinz’s (1978) multimode theory - Measured the amount of resources required to shadow using a dual task procedure. - Participants shadowed on either the basis of pitch (early) or semantic category (late) - Viewed a computer monitor and had to hit a button quickly whenever a dot appeared on the screen (detection). Results Attention No list 1 list 2 lists 2 lists (pitch) (semantic) Detection time310 ms 370 ms 433 ms 482 ms Shadowing errors n/a 1.4% 5.3% 20.5%

Attention The cell phone diversion –Strayer’s Research > Used a driving simulator  Single vs. dual task  Hands free vs. hand held No difference >Can drivers recognize objects that they have fixated on?  Recognition accuracy for fixated objects about half when conversing Even when fixation duration is equated performance was far worse >The inattentional blindness hypothesis  Cell-phone conversation disrupts performance by diverting attention from the external environment associated with the driving task to the cellphone converstation.  DemoDemo Attention

The cell phone diversion –Strayer’s Research > What about strategic reallocation?  There are important and unimportant objects >Two-Alternative forced choice recognition  Drivers rated the importance of the items. >Performance was significantly poorer in the dual task.  even when fixation duration is controlled.  Absolutely no effect of the importance of the object on the inattentional blindness effect. Attention

The cell phone diversion –Strayer’s Research >Conversing on the phone vs. with a passenger >Instructed to drive 8 miles down a freeway and exit at a truck stop.  Only 12% of drivers with a passenger missed the exit.  About 50% talking on a cell phone missed the exit The passengers assisted the drivers Attention

The cell phone diversion –Strayer’s Research >Conversing and driving vs. drinking and driving  Car-tailing paradigm  Compared.08% alcohol intoxication with hands held and hands free. No differences were observed between the cell phone conditions Both Alcohol and phone groups showed impaired driving 4 of the cell phones talkers rear-ended the pace car (none of the drinkers had a collision) Attention