V. Thought and Behavior: Do we control our own minds? Brain, Mind, and Belief: The Quest for...

V. Thought and Behavior: Do we control our own minds?

Brain, Mind, and Belief: The Quest for Truth

... the brain creates a picture -- a simulation that we mistake for reality. George Johnson

Today’s Agenda

Traveling the brain's pathways Thinking with categories Unconscious influences on behavior

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Operations in neurocognitive networks

Activation moves along lines and through nodes (along the pathways of the brain)

• Integration • Broadcasting

Connection strengths are variable• A connection becomes stronger with repeated

successful use• A stronger connection can carry greater activation

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REVIEW

Some nodes of the cortical net for fork

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Each node in this diagramrepresents a cortical column

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C — conceptualM — motorT — tactileV — visual

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Some nodes of the cortical net for fork

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Some nodes of the cortical net for fork

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A word network with two subnets partly shown

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Visual features

C – Cardinal concept nodeM – MemoriesPA – Primary auditoryPP – Phonological productionPR – Phonological recognitionT – TactileV – Visual

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Ignition of a word network from visual input

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Speaking as a response to ignition of a net

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Speaking as a response to ignition of a net

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Speaking as a response to ignition of a net

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From here (via subcortical structures) to the muscles that control the organs of speech articulation

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An MEG study from Max Planck Institute

Levelt, Praamstra, Meyer, Helenius & Salmelin, J.Cog.Neuroscience 199824

Thinking: Traveling the pathways of the brain

Starting a trip through the brain’s pathways• Often induced by sensory input

Hearing the telephone ring Seeing your cat scratching a favorite chair

• Often initiated internally Using information already present in the mind

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Internally induced mental processing

Operates with previously acquired information Deduction, induction, reasoning, figuring things out,

connecting the dots, … Examples: thinking about ..

• The story that Santa comes down the chimney• The story of Noah’s ark and the great flood

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Today’s Agenda

Traveling the brain's pathways Thinking with categories Unconscious influences on behavior

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Categories and reality

• Categories are in the mind, not in the real world • In the world, everything

is unique lacks clear boundaries changes from day to day

• (even moment to moment)• Whorf: “kaleidoscopic flux”

Types of Conceptual Categories

Discrete – clear boundaries• Even integers• Towns in MA

Radial – membership comes in degrees• Birds• Vehicles

Family resemblance• Games• Furniture

Ill-defined, vague• Thought• Mind

Properties of radial categories

1. No small set of defining features • Example: CUP

• What’s the difference between a cup and glass?2. Fuzzy boundaries

• Example: VEHICLE Car, truck, bus Airplane? Boat? Toy car, model airplane? Raft? Roller skate? Snowboard?

3. Prototypicality• Prototypical vehicles: CAR, TRUCK, BUS• Peripheral vehicles: AIRPLANE, TOY CAR, RAFT, ROLLER SKATE, etc

How do radial categories work?

We can understand how they work by understanding how they are represented in the cortex

Different connections have different strengths (weights) More important properties have stronger connections For CUP,

• Important properties: Short (as compared with a glass) Ceramic Having a handle

• These properties are not necessary • But cups with these properties are more prototypical

The properties of a category have different weights

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CUP

MADE OF GLASS

CERAMIC

SHORT

HAS HANDLE

The properties are represented by nodes, which are connected to lower-level nodes

The cardinal node

The threshold

More important properties have greater weights, represented by greater thicknesses of lines

Activation of a category node

The node will be activated by any of many different combinations of properties

The key word is enough – it takes enough activation from enough properties to satisfy the threshold

The node will be activated to different degrees by different combinations of properties• When strongly activated, it transmits stronger

activation to its downstream nodes.

Radial categories and inference

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CUP

MADE OF GLASS

CERAMIC

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HANDLE

These connections are bidirectional

Separate fibers for the two directions; shown as one line in the notation

An important finding from neuroanatomy

Cortico-cortical connections are generally reciprocal• If there is a connection from A to B there is also a

connection from B to A Consequence: Bidirectional processing

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Bidirectional processing and inference

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CUP

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HANDLE

Thought process: 1. The cardinal concept node is activated by a subset of its property nodes 2. Feed-backward processing activates other property nodes

Consequence: We “apprehend” properties that are not actually perceived

Category Structure and Inference

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Properties

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Consequence:

If A and B, then E and F

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Examples

Dark clouds, thunder• It’s going to rain

Ceramic, cup-shaped, handle• Probably holds coffee (without breaking)

ATM• Probably has money

Afro-American trying to break into house• Must be a burglar

Categories and cognitive malfunction

Underdifferentiation• Assuming that members of a category are alike

Illusory properties• Assuming that a category has one defining feature• Assuming that members of a category share some

properties that are lacking in those outside the category

Illusory category boundaries• Or: failure to recognize ‘fuzziness’

Categories and cognitive malfunction

Underdifferentiation• Assuming that members of a category are alike

Illusory properties• Assuming that a category has one defining feature• Assuming that members of a category share some

properties that are lacking in those outside the category

Illusory category boundaries• Or: failure to recognize ‘fuzziness’

Category errors with consequences Example: Dietary fats

Original report: JAMA, 8 Feb 2006 Big news: Front page of NY Times. Etc. “Landmark Study”

• 48,835 women• Eight years• $415 million

Study finds that reducing fat intake does not confer health benefits

Co-author: JoAnn Manson, chief of preventive medicine at Harvard’s Brigham and Women’s Hospital• MSNBC: “…respected nutrition authority”

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Category errors with consequences Example: Dietary Fats

MSNBC: 8 Feb 2006: Study: Low-fat diet fails to decrease cancer, heart risks in older women“Eating less fat late in life failed to lower the risk of cancer and heart disease among older women, disappointing news for those who expected greater benefits from a healthy diet.” …“The eight-year study showed no difference in the rate of breast cancer, colon cancer, and heart disease among those who ate low-fat diets and those who didn’t.”…“The study, appearing in Wednesday’s Journal of the American Medical Association, is part of … a landmark government project involving tens of thousands of … U.S. women.”

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Exercise: What is wrong with this study?And with the press report on this study?

Answer: They didn’t consider the differences between different kinds of fat

A category error• All members of the category treated as alike

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There are different kinds of FAT

From the web site of the FDA

Polyunsaturated Canola oil Good

Monousaturated Olive oil Very good

Saturated Butter A little is OK

Transfat Margarine Really bad

Type of Fat Example Good/Bad

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Categories and cognitive malfunction

Underdifferentiation• Assuming that members of a category are alike

Illusory properties• Assuming that a category has one defining feature• Assuming that members of a category share some

properties that are lacking in those outside the category

Illusory category boundaries• Or: failure to recognize ‘fuzziness’

Illusory properties

• Assuming that a category has one defining feature• Example: MAN

What is it that distinguishes humans from other animals?

Proposal: “tool-making animal” (Caution: TOOL is a category)

• Assuming that members of a category share some properties that are lacking in those outside the category White supremacy

Categories and cognitive malfunction

Underdifferentiation• Assuming that members of a category are alike

Illusory properties• Assuming that a category has one defining feature• Assuming that members of a category share some

properties that are lacking in those outside the category

Illusory category boundaries• Or: failure to recognize ‘fuzziness’• Example: BEARD

Today’s Agenda

Traveling the brain's pathways Thinking with categories Unconscious influences on behavior

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Unconscious influence of language on behavior:Experiments with “scrambled sentence test”

Experiments by John Bargh and colleagues• Bargh, Chen, and Burrows, 1996

Scrambled sentence test• “The purpose of the study is to investigate

language proficiency”• Task: Write down a grammatically correct

sentence using only four of the five words given

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Sample “scrambled sentence” data

him was worried she always shoes give replace old the sky the seamless gray is should now withdraw forgetful we us bingo sing play let sunlight makes temperature wrinkle raisins from are Florida oranges temperature be will sweat lonely they

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Two sets of scrambled sentence data

Experimental group• worried, old, gray, forgetful, bingo,

wrinkle, selfishly, careful, sentimental, wise, stubborn, courteous, withdraw, retired, rigid, traditional, bitter, obedient, conservative, knits, dependent, ancient, helpless, gullible, cautious, alone

Control group• Neutral words

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“Elderly priming condition”

Trigger words in the “scrambled sentence” data

him was worried she always shoes give replace old the sky the seamless gray is should now withdraw forgetful we us bingo sing play let sunlight makes temperature wrinkle

raisins from are Florida oranges temperature he will sweat lonely they

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Trigger words in the “scrambled sentence” data

him was worried she always shoes give replace old the sky the seamless gray is should now withdraw forgetful we us bingo sing play let sunlight makes temperature wrinkle

raisins from are Florida oranges temperature he will sweat lonely they

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After the subject finished..

Experimenter partially debriefed subject• “… how people use words in various flexible ways”

Experimenter tells subject that elevator is down the hall Subject leaves, walks down the hall: 32 feet Confederate uses stopwatch to measure time taken to

walk the 32 feet Then experimenter gives complete debriefing

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Results

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(9.75 meters is about 32 feet)

Second experiment (for replication) , with first

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Another experiment (Bargh, Chen & Burrows, 1996)

Scrambled sentence test – 30 items• E.g., “he it finds instantly”

34 subjects (NYU psych students) Three versions of test given to 3 subgroups

1 Words associated with concept RUDE 1 aggressively, bold, rude, bother, disturb, intrude,

annoyingly, interrupt, audaciously, brazen, impolitely, …

2 Words associated with concept POLITE1 respect, honor, considerate, appreciate, patiently, cordially,

yield, polite, cautiously, courteous …

3 Neutral words1 exercising, flawlessly, occasionally, rapidly, practiced…

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Experimental procedure

Neither the experimenter nor the confederate knew which priming condition was being used with each subject

After finishing, subject was to go to see the experimenter in another room down the hall

Confederate posed as a subject who was having trouble understanding directions, kept asking questions of the experimenter

Test measure: How long did the subject wait before interrupting the experimenter?

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Experimental procedure (cont’d)

Ten minute limit Debriefing, including question: subject was asked

how the scrambled sentence test might have influenced them during the rest of the procedure• None of the subjects showed any suspicion of

influence of the scrambled sentence test Further debriefing: subjects were asked whether

experimenter had been polite• Scale from –3 to +3

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Results: Mean time before interrupting

RUDE priming condition• 326 sec

Neutral condition• 519 sec

POLITE priming condition• 558 sec• N.B.: almost 10 minutes• But 21 of the 34 did not interrupt at all

during the ten-minute time period!

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Percentage of subjects who interrupted

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Polite Neutral Rude

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Unconscious influences of language on behavior

The experiments show a clear influence of language on behavior

The influence is unconscious How does it work?

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Explanation in terms of brain structure

Bidirectional connections• A hypothesis verified by neuroanatomy

Consequence: reverberating activation The activation levels increase with repeated

activation

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AB

Consequences of repeated activation

Links become stronger• A lasting effect• A primary factor in the learning process

Nodes become more highly activated• Short-term effect• When more highly activated, sends out

stronger activation

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Priming and reverberating activation

worriedold

gray

forgetful

bingo

wrinkle

careful wise

retired

traditional

helplesscautious

alone Florida

SLOW

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This word was NOT in the data presented

Unconscious influence of language on behavior:Mars

In 1997 the first Mars Rover landed on Mars• Propelled on a U.S. Pathfinder rocket

Results• Sales of Mars Rover toys increased dramatically

No surprise• Sales of Mars candy bars increased dramatically

(named for company founder Franklin Mars)

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Functional layout of the gray matter

Primary areas: • Visual (occipital)• Auditory (temporal)• Somatosensory (parietal)• Motor (frontal)

Secondary areas Association areas Executive area, in prefrontal lobe

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Primary motor and somatosensory areas

Central Sulcus

Sylvian fissure

Primary Motor Area

Primary Somato-sensory Area

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Divisions of Primary Motor and Somatic Areas

Primary Somato-sensory Area

Primary Motor Area

Primary AuditoryArea

PrimaryVisual Area

Mouth

HandFingers

Arm

Trunk

Leg

Higher level motor areas

Primary Somato-sensory Area

Actions performedby hand

Primary AuditoryArea

PrimaryVisual Area

Mouth

HandFingers

Arm

Trunk

Leg

Actions per-Formed by leg

Actions performedby mouth

Primary Somato-sensory Area

Primary Motor Area

Primary AuditoryArea

PrimaryVisual Area 71

Conceptual structure: in higher-level cortical areas

Verbal concepts

NominalConcepts

Verbal concepts (the meanings of verbs)

They get reinforced, hence strengthened, by repeated activation• And activation spreads automatically among related

concepts, because they are interconnected If they were not interconnected, they wouldn’t be

related

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Observations from Bargh 2009

Related cognitive neuroscience research has shown an automatic connection between behavioral concept representations and their corresponding motor representations

Merely hearing action verbs pronounced out loud activates the same brain region (Brodman 45) as does witnessing a meaningful action (Jeannerod, 1999)• Both activate implicit motor representations needed to

carry out that type of behavior (Perani et al., 1999)• Motor programs thus appear to be part of the very

meaning of action-related verbs (Grezes & Decety, 2001; Pulvermuller, 2005)

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Concepts associated with rudeness

DISTURB BRAZEN

BOTHER BOLD RUDE

INTRUDE

IMPOLITELY INTERRUPTAGGRESSIVELY

AUDACIOUSLY ANNOYINGLY

As these concepts are all activity-related, they are all presumably located in the frontal/prefrontal lobes. In the experiment they were triggered by visual linguistic input.

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Percentage of subjects who interrupted

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Polite Neutral Rude

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Another experiment (Harris, Pierce, & Bargh, 2013):Anti-smoking PSAs and smoking behavior

56 smokers watched a short television segment that included a commercial break that showed a public service announcement

Randomly placed in one of three groups acc. to type of PSA• Group 1: a Philip Morris “Quit-Assist” PSA• Group 2: a Legacy “Truth” anti-smoking PSA• Group 3: a control PSA (not about smoking at all)

Subjects were given a brief break after TV viewing• They were left alone during this break• They had the option of going outside for a smoke

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Anti-smoking PSAs and smoking behavior: Results

Subjects were given a brief break after TV viewing• They were left alone during this break• They had the option of going outside for a smoke

Group 1: a Philip Morris “Quit-Assist” PSA• 42% smoked during the break

Group 2: a Legacy “Truth” anst-smoking PSA• 33% smoked during the break

Group 3: a control PSA (not about smoking at all)• 11% smoked during the break

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Results

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Percentage of participants who smoked following exposure to public service announcement

T h a t ‘ s i t f o r t o d a y !

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