The Psychology Book (21 page)

62

PROFITLESS
IN CONTEXT

APPROACH

Connectionism

BEFORE

ACTS ARE

1885
In his book
On Memory
,

Hermann Ebbinghaus

describes the “forgetting

curve”—the rate at which

human memories fade.

1890s
Ivan Pavlov establishes

the principle of classical

STAMPED OUT conditioning.

AFTER

EDWARD THORNDIKE (1874–1949)

1918
John B. Watson’s “Little

Albert” experiments apply

conditioning to a human baby.

1923
English psychologist

Charles Spearman proposes

a single general factor—the

“g factor”—in measurements

of human intelligence.

1930s
B.F. Skinner develops

a theory of conditioning from

consequences—“operant

conditioning”.

A
t much the same time as

Pavlov was conducting his

experiments on dogs in

Russia, Edward Thorndike began

researching animal behavior for

his doctoral thesis in the US.

He was perhaps the first true

“behaviorist” psychologist,

although his research took place

long before the term was adopted.

Scientific psychology was

emerging as a fresh field of study

in universities when Thorndike

graduated in the 1890s, and he

was attracted by the prospect of

applying this new science to his

interest in education and learning.

Thorndike’s original intention had

been to study learning in humans,

BEHAVIORISM 63

See also:
Hermann Ebbinghaus 48–49 ■ Ivan Pavlov 60–61 ■ John B. Watson 66–71 ■ Edward Tolman 72–73 ■

B.F. Skinner 78–85 ■ Donald Hebb 163 ■ Hans Eysenck 316–21

When an

animal responds

to a stimulus…

Psychology helps to

measure the probability

that an aim is attainable.

Edward Thorndike

…the outcome may

…the outcome may

be
rewarding

be
profitless

(such as escaping from

(such as still being

a cage).

trapped in a cage).

but when he was unable to obtain

a suitable subject for his research,

he turned his attention to animals,

with the aim of examining the

The connection between

The connection between

processes of intelligence and

the action and the event

the action and the event

learning through observation in

is
strengthened
.

is
weakened
.

a series of controlled experiments.

Thorndike’s results went much

further than this, however,

laying down the foundations

of behaviorist psychology.

Learning environments

Thorndike’s first studies were

Rewarded responses are

of chicks learning to negotiate

“stamped in,” while profitless

mazes that he designed and built

acts are “stamped out.”

specifically for his experiments.

This later became a hallmark

of behaviorist experimental

technique—the use of a specially

created environment in which a

subject is given specific stimuli or

various devices, such as a loop of

box each time; this indicated how

tasks, now known as “instrumental

string, or a ring, or a button or

quickly the animal was learning

conditioning” or “instrumental

panel to be pressed, only one of

about its environment.

learning.” As his research

which would be connected to the

The experiment was carried out

progressed, Thorndike turned his

latch that would open the door of

using several different cats, placing

attention to cats, inventing “puzzle

the box. In time, the cat would

each one in a series of puzzle boxes

boxes” to observe their ability to

discover the device, which would

that were opened by different

learn mechanisms for escape.

allow it to escape and receive a

devices. What Thorndike noticed

A hungry cat was locked inside

reward of food. The process was

was that although the cats had all

a puzzle box, and by exploring its

repeated and it was noted how long

discovered the escape mechanism

environment would come across

it took for the cat to open the puzzle

by trial and error in their first ❯❯

64 EDWARD THORNDIKE

as a neural connection. When

stimulus-response sequences

are followed by an annoying or

unpleasant state of affairs (such

as continued imprisonment or

punishment), the neural connections

between the situation and response

are weakened, until eventually

“profitless acts are stamped out.”

This focus on the outcome of a

stimulus and its response, and the

idea that the outcome could work

back to strengthen the stimulus-

response connection, is an example

of what would later be called a

reinforcement theory of learning.

Reinforcement, and the importance

of outcomes, was virtually ignored

by psychologists in the next

generation of behaviorists, such

The Law of Effect
, proposed by Thorndike, forms

as John B. Watson, but the Law of

the foundation of all behaviorist psychology. He

Effect brilliantly anticipated the

demonstrated that animals learn by forging links

between actions and results, remembering more

work of B.F. Skinner and his theory

positive outcomes and forgetting negative ones.

of “operant conditioning.”

In later research, Thorndike

refined the Law of Effect to take

attempt, on successive occasions

between a stimulus (S) and a

into account other variables, such

the amount of trial and error

response (R), a corresponding

as the delay between response and

gradually decreased as the cats

neural connection is made in the

reward, the effect of repetition of a

learned which actions were going

brain. He referred to his brand of

task, and how quickly a task was

to be fruitless and which would

S-R learning as “connectionism,”

forgotten when it was not repeated.

lead to a reward.

asserting that the connections

From this, he derived his Law

made during learning are “stamped

of Exercise, which states that

The Law of Effect

in” the circuitry of the brain.

As a result of these experiments

What Thorndike proposed was

Thorndike proposed his Law of

that it is the outcome of an action

Effect, which states that a response

that determines how strongly or

to a situation that results in a

weakly the stimulus-response

satisfying outcome is more likely

connection is stamped in; in the

to occur again in the future; and

case of the puzzle boxes, whether

The intellect, character, and

conversely, that a response to

pulling a string or pushing a panel

skill possessed by any man

a situation that results in an

resulted in escape or frustration.

are the product of certain

unsatisfying outcome is less likely

In other words, when particular

original tendencies and

to occur again. This was the first

stimulus-response sequences are

the training which they

formal statement of an idea that lies

followed by a satisfying or pleasant

have received.

behind all behavorist psychology,

state of affairs (such as escape or a

Edward Thorndike

the connection between stimulus

reward), those responses tend to

and response and its relevance

become “more firmly connected

to the process of learning and

with the situation, so that, when it

behavior. Thorndike proposed

recurs, they will be more likely to

that when a connection is made

recur.” They become “stamped in”

BEHAVIORISM 65

intelligence, never about animal

stupidity,” he wrote. The fact that

his cats in puzzle boxes learned

gradually, rather than suddenly

gaining an insight into how to

escape, confirmed his theories.

The animals were forced to learn

by trial and error, because they

were unable to use reason to work

out the link between the door and

the operating handle.

Human intelligence

After the publication of
Animal

Edward Thorndike

Adult learners
were once thought to

Intelligence
, Thorndike turned his

be less capable of retaining information

attention to human intelligence.

The son of a Methodist

than children. Thorndike showed that

minister, Edward Thorndike

In his opinion, the most basic

the only significant difference was in

was born in Williamsburg,

intelligence is characterized by

speed of learning, not memory.

Massachusetts, USA, in 1874.

simple stimulus and response

He graduated in sciences from

association, resulting in a neural

Wesleyan University in 1895,

stimulus-response connections

connection. The more intelligent

proceeding to Harvard to

that are repeated are strengthened,

an animal, the more capable it will

study psychology under

while those that are not used again

be of making such connections.

William James. In 1897,

are weakened. Moreover, the rate

Therefore, intelligence can be

Thorndike moved to Columbia

at which connections strengthen

defined in terms of the ability to

University in New York City,

or weaken can vary. According

form neural bonds, which is

where he completed his

to Thorndike, “the greater the

dependent not only on genetic

doctorate thesis in 1898.

satisfaction or discomfort, the

factors, but also on experience.

Thorndike’s interest in

greater the strengthening or

To find a measurement of

educational psychology led

weakening of the bond.”

human intelligence, Thorndike