A metaphor of black box is usually described to explain the behaviorist approach about learning, i.e. the learner is a black box and nothing is known about what goes on inside. Knowing what's inside the black box is not essential for determining how behavior is governed by its environmental antecedents and consequences. The behaviorists believe that the psychology as a science to develop a reliable and useful theory of learning have to use observable, reliable data as evidence.

To behaviorism, learning is a behavioral change. The behaviorists put a strong emphasis on association and analysis on nurture over nature in determining human and animal behavior. They conduct conditioning experiments to provide an objective way to investigate associations. Behaviorism employed the hypotheico-deductive method of scientific study on animal and human behaviors. Pavlov's Nobel Prize winning research initiated the views of learning in terms of stimulus-response linkages and transfer; Thorndike's puzzle box established that a Stimulus-Response bond is selectively strengthened by its satisfying consequences. Skinner's work drew attention to the responses of the organism that produce the reinforcing or rewarding goal object. Skinner described behavioral change as a function of response consequences. It is the outcome produced by the action that causes the behavioral change.

Theoretical Foundations
Ivan Pavlov's work on the physiology of the digestive system instigated the behaviorist movement in psychology. His discovery has come to be known as classical conditioning. The methodological and conceptual framework employed in Pavlov's observations was adapted by John Watson. Watson's experiment with Albert, who was conditioned for his fear reaction to furry animals and objects, demonstrated Watson's belief that human personality developed through the conditioning of various reflexes. Different from Pavlov and Watson, Edward Thorndike, another major contributor, focused his research on voluntary behaviors. Thorndike's experimental interest lies in the establishment of connections between particular stimuli and voluntary behaviors. He formulated three laws of Readiness, Exercise, and Effect to illustrate how human acquire connections productive of behavior suitable to the environment in which they live (Thorndike, 1921).

Arguing that a simple stimulus-response formula cannot explain a large part of behavior which is not under control of eliciting stimuli, Skinner made distinctions between respondent behavior and operant behavior. According to Skinner, acquisition of behavior is viewed as resulting from a three-component contingent relationship. The interconnected relationship is between the stimuli that precede a response (antecedents/discriminative stimuli), the stimuli that follow response (consequences/reinforcing stimuli), and the response (operant) itself.

Three major theoretical assumptions dominate the filed of behaviorism: Classical Conditioning, Thorndike's connectionism, and Skinner's Operant Conditioning.

Classical Conditioning
Pavolv's study of classical conditioning proposed that a response comes to be established by its association with an environmental stimulus. In such form of learning, a stimulus or an event can predict the occurrence of another stimulus and event. In other words, humans develop their behaviors by a set of stimulus-response associations.

Learning occurs in establishing the S-R association. When the association between the neutral stimulus and a reflex response to an unconditional stimulus is established, the nature of the association is transformed from unconditional to conditional. Anderson (1985) reviewed the mechanism of associative bonding in classical conditioning, and commented that this particular theoretical assumption provided an objective language of stimuli and responses to talk about subjective phenomena. It started to establish the common ground of the scientific study of behavior.

Aimed to discover the functional relationship between environmental events and behavior, behaviorists collected their data from controlled laboratory experiments. Moreover, they emphasized the need for rigorous experimentation and carefully defined variables. Variables manipulated in classical conditioning:

• Amplitude: the amount or strength of the response
• Latency: the length of time between the stimulus and the response

Hypothetical processes and relationships include:

• Stimulus generalization: the tendency of similar stimuli to elicit the reflex
• Resistance to extinction: the tendency of a response to persist after the supporting conditions are withdrawn.
• Inhibition: the reduction in a response caused by the introduction of extraneous stimuli

The research was limited to conditioning of involuntary behaviors:

• conditioning of reflex actions, e.g. salivation and finger jerk
• conditions of emotions, e.g. Albert's fear for furry animals

Thorndike's Connectionism
Thorndike (1913) posited that a man's intellect, character, and skill is the sum of his tendencies to respond to situations and elements of situations, and it is the different situation-response connections that make up this sum of the world. He was interested in the doctrine of association between sensation and impulse.

Thorndike studies voluntary behaviors. His experiment on the animal's escape behavior in the puzzle box demonstrated an associating process between a situation and a response in trial and error learning. Gredler (1997) has pointed out that the importance of Thorndike's research is to include the effects of the subject's action among the causes of behavior change. A connection is made between the stimulus of the environment, the behavior and the consequences. Three major laws of learning to explain this process include:

1. Law of Effect: The strength of the connection is determined by the state of satisfyingness following the response.
2. Law of Exercise: The strength of the connection is influenced by the use and disuse of the connection. The recurrence of the condition increases the connection's strength. But when a connection is not made between a situation and a response during a length of time, that connection's strength is decreased.
3. Law of Readiness: Whether a conduction unit is in readiness to conduct or not is governed by the states of satisfying and annoying.

According to Thorndike, learning can be explained as a series of the connections between the environmental stimuli and behaviors followed by reinforcing consequence, governed by law of effect, law of exercise and law of readiness.

Skinner's Operant Conditioning
Operant Conditioning, developed by Skinner in 1938, recognizes the differences between elicited responses and emitted responses. The former are responses associated with a particular stimulus, and the latter are responses that act on the environment to produce different kinds of consequences that affect the organism and alter future behavior. Skinner's research focuses on the manipulation of the consequences of an organism's behavior and its effect on subsequent behavior. Learning can be understood by a basic S (Discriminative Stimulus)-R (Operant Response, the behavior)-S (Contingent Stimulus, the reinforcing stimulus) relationship. The change in behavior is operated by the contingencies of reinforcement. A reinforcing event is any behavioral consequence that strengthens behavior.

Skinner's research focused on the experimental study of behavior. The underlying assumptions about the research in Skinner's experiments include:

• The lawful relationships between behavior and environment can be only found only if behavioral properties and experimental conditions are carefully studied
• Data from experimental study of behavior are the only acceptable sources of information about the causes of behavior.

Skinner (1938) proposed two laws that govern the conditioning of an operant:

• The Law of Conditioning: If the occurrence of an operant is followed by presentation of a reinforcing stimulus, the strength is increased.
• The Law of Extinction: If the occurrence of an operant already strengthened through conditioning is not followed by the reinforcing stimulus, the strength is decreased.

Learning principles

Based on the leaning mechanism of bridling the S (Discriminative Stimulus)-R (Operant Response, the behavior)-S (Contingent Stimulus, the reinforcing stimulus) relationship, the components of instruction includes selecting stimulus and providing reinforcement. In the learning processes, the learners learn to discriminate and generalize stimuli in order to respond appropriately.

Three principles for teaching new and complex behaviors are defined by behaviorists: shaping, chaining, and fading.

Shaping
Shaping refers "the reinforcement of successive approximations to a goal behavior" (Driscoll, 2000). This process requires the learner to perform successive approximations of the target behavior by changing the criterion behavior for reinforcement to become more and more like the final performance. In other words, the desired behavior is reinforced each time only approximates the target behavior.

Chaining
Skinner also provided the explanation of the mechanism underlying the nature of complex learning. He proposed that the acquisition of complex behaviors is the result of the process referred to as chaining. Chaining establishes "complex behaviors made up of discrete, simpler behaviors already known to the learner" (Driscoll, 2000).

Fading
According to behaviorists, behaviors are acquired and exhibited because they are reinforced; non-reinforced behaviors tend not to occur. Individuals are clearly able to distinguish between settings in which certain behaviors will or will not be reinforced. The concept of fading refers to "the fading out of discriminative stimulus used to initially established a desired behavior" (Driscoll, 2000). The desired behavior continues to be reinforced as the discriminative cues are gradually withdrawn.

Theory into Practice: The importance to Instructional Systems Design
Behavioral psychology has provided instructional technology with some basic assumptions, concepts and principles. Three major assumptions are directly relevant to instructional technology (Burton, Moore, Magliaro, 1996):

1. The role of learner: knowledge is action. The emphasis is on the active responding of the learner. The learner must be engaged in the behavior in order to learn and to validate that learning has occurred.
2. The nature of learning: Learning is defined as a change in behavior due to a function of building associations between the occasion on which the behavior occurs (stimulus events) and the behavior itself (response events).
3. The generality of learning principles: The basic processes that promote or inhibit learning are universal to all organisms.

Burton, Moore, and Magliaro (1996) also states the impact of behavioral psychology on the tools of the field of instructional technology in its methodological approach to the learning research and film research projects in the field.

The influence of behaviorism on instructional systems design is widely identified in the following aspects (Burton, Moore, and Magliaro, 1996; Saettler, 1990; Shrock, 1995):

• Task analysis, behavioral objectives
• Teaching machines (Pressey, 1964): Automation has been viewed as the solution to the problem of providing immediate reinforcement for correct responses in instruction.
• Programmed instruction (Skinner, 1958): Applying the learning principle of shaping, the content is arranged in small steps, which progress from simple to complex and require a response from the learner to go on.
• Computer-assisted learning (Driscoll, 2000): (1) Depending on how students answer a given question, the frames are branched to other segments of the program. The use of branching in the instruction increases instructional flexibility and improve the linear style of the program; (2) As a result, instructional software is increasing available that provide drill and practice on various academic skills, simulations to enhance problem-solving, or tutorials in various subject matters.
• Systems approach to the design on instruction

Driscoll (2000) explains the role of feedback in improving performance in organizational systems from the perspective of the behavior management quite clearly.

1. Feedback is the consequence of a response, typically reinforcement for an appropriate behavior. Also, feedback provides information to the learner as to how performance should be.
2. Feedback is one of several environmental factors that support or hinder exemplary performance in an organization. The researchers concluded that analysis of the work environment is critical for managing performance improvement
3. Planning for performance improvement is a process analogous to planning for behavior management or modification. Once the desired performance has been determined and the gap is identified between what it is and what it should be, appropriate rewards and incentives for performance can be selected. Then a plan is generated, implemented, evaluated, and revised as necessary.

Task Analysis
The concept of chaining, i.e. the acquisition of complex behaviors is made up of discrete, simpler behaviors already known to the learner, results in a hierarchical analysis of the desired learning outcomes in order to design sequences of stimuli-responses reinforcements for complex learning.

Moreover, the idea of learning as "behavioral changes" gave arise to the development of behavioral objectives. It is important to specify desired instructional outcomes in terms of clear, observable behavior.

Mager (1962): three component objective: the behavior to be acquired, the conditions under which the behavior is to be demonstrated, and the criteria governing how well the behavior is to be performed.

Design
Outcome-oriented instruction was more recognized. From the perspective of Skinner's operant conditioning, in which learning is understood by a basic S (Discriminative Stimulus)-R (Operant Response)-S (Contingent Stimulus) relationship. Moreover, change in behavior is operated by the contingencies of reinforcement. Thus, instructional strategies, such as reinforcement, rewarding, and immediate feedback, have been emphasized.

Development
Skinner is one of the major advocates of teaching machines and programmed learning. The use of computers to convey individualized learning materials fits Skinner's ideology of carefully controlled stimulus-response reinforcement.

Evaluation
In the early 1960s, there is an emergence of criterion-referenced testing, i.e. to measure how well an individual can perform a particular behavior or set of behaviors, irrespective of how well others perform. Moreover, criterion-reference testing can be used to assess student entry-level behavior and to determine the extent to which students had acquired the behaviors an instructional program was designed to teach.

References:

Burton, J. K., Moore, D. M., & Magliaro, S. G. (1996). Behaviorism and instructional technology. In D. H. Jonassen (Ed.), Handbook of Research for Educational Communications and Technology (pp. 46-73). New York: Macmillan.

Drisoll, M. P.( 2000). Psychology of learning for instruction. 2nd. Needham Heights, MA: Allyn and Bacon.

Gredler, M. E. (1997). Learning and instruction: Theory into practice. Upper Saddle River: Prentice-Hall.

Saettler, P. (1990). The evolution of American educational technology. Englewood, CO: Libraries Unlimited Inc.

Shrock, S. A. (1995). A brief history of instructional development. In G. J. Anglin (Ed.),
Instructional technology: Past, present and future (Second ed., pp. 11-18). Englewood, CO: Libraries Unlimited Inc.

Skinner (1938). The behavior of organisms. New York: Appleton-Century-Crofts.

Thorndike, E. L. (1913). Educational psychology: Vol. 1. The original nature of man. New York: Teacher's College Press.

Thorndike, E. L. (1913). Educational psychology: Vol. 2. The psychology of learning. New York: Teacher's College Press.

Waston, J. B. (1913). Psychology as the behaviorist views it. Psychological Bulletin, 20, 158-177.