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SKILL ACQUISITION IN THE PRESENCE AND ABSENCE OF CUES 1

Running head: SKILL ACQUISITION IN THE PRESENCE AND ABSENCE OF CUES

Measuring skill acquisition in the presence and absence of guiding cues in pigeons

Nathan Folks, Jordan Hardy, Sydney Kline, Carrie Martin, and N. Hunter Rackett

Wofford College

AresearchthesissubmittedinpartialfulfillmentoftheBachelorofSciencedegreeinPsychologyfromWoffordCollege

May2012

Dr. Alliston Reid Department of Psychology Wofford College 429 N Church Street Spartanburg, SC 29303 864-597-4642 [email protected]


Abstract

The purpose of this study was to examine skill acquisition in the presence and absence of cues.

Previous research has shown an effect of guidance in the presence of cues in the initial learning

of skills. In this study, we expected to see an initial effect of guiding cues on left-right sequence

accuracy. Eight pigeons were separated into four groups that were divided into conditions based

on a combination of guiding cues and no cues conditions. There were two possible conditions for

guiding cues, Follow-Red and Red-Green, and two No-Cues conditions, Both-Green and Both-

Red. Both groups internalized the left-right sequence with practice in the absence of guiding

cues. Two subject groups learned differently due to the difference in complexity in guiding cues.

After the conclusion of the first procedure, a second procedure was added to determine the

difference between what each subject group learned about the left-right sequence. Results

showed an effect of guiding cues on learning, and practice led to an internalization of the left-

right sequence. The more complex guiding cues condition resulted in a better grasp of the left-

right sequence. The study concluded that independently practicing a skill led to sustained

performance.


Measuring skill acquisition in the presence and absence of guiding cues in pigeons

What do walking, drawing, and throwing a touchdown pass have in common? They are

all considered skills humans acquire by watching others and by practicing the behavior. Gluck,

Mercado, and Myers (2008) define a skill as an ability that improves over time through practice.

One common model for skill acquisition in humans is the Fitts three stage cognitive model of

skill learning. The three stages that composed the model are the cognitive, associative, and

autonomous stages. While the model provides useful information in some skill acquisition

scenarios, the model is too complicated overall and only applies to the learning of some skills,

particularly in humans. The limitations of the model start with the first cognitive stage, which

characterizes verbalized rules as a basis for performance. Research has shown evidence of an

animal’s ability to learn new skills without the use of verbalized commands and rules. The Fitts

model fails to adequately explain the simplest forms of skill acquisition and cannot be

generalized across species. Research concerning skill learning continues to be explored in an

attempt to develop a more inclusive model that satisfactorily explains the acquisition of skills

and applies to both humans and nonhuman species. Animal studies provide insight into how skill

acquisition occurs and their results have been used to relate the process of learning skill

acquisition to humans.

Specifically, researchers use animal studies to study the association between an animal’s

behavior and certain stimuli in the environment that initiate and improve learning over time. One

of the most common methods through which animal skill acquisition is studied is through lever

pressing in rats and key pecking in pigeons. Light cues guide rats’ and pigeons’ behavior toward

lever pressing and pecking sequences that result in reinforcement. Information about the rats’


and pigeons’ responses to cues is then related to humans and how humans learn skills under the

influence of cues.

The Rescorla Wagner (RW) model is helpful in explaining how stimulus cues are used in

learning skills (Rescorla-Wagner, 1972). As a stimulus in a trial is conditioned, the properties

surrounding it in terms of antecedent cues and what those suggest about behavior become more

familiar through training and the associative value related to the meaning of the stimulus

increase. The model can explain rapid response rates toward a certain stimulus. One weakness

found in the RW model, however, is that it gives most of its attention to one property of a

stimulus in a learning process, preventing other properties of a stimulus to be taken into account.

Learning progresses at a rapid pace the more the stimulus and its associative value are combined,

eventually leading to what is called the power law of learning. The power law of learning occurs

when learning has reached a maximum level and cannot be improved because there is no more to

learn. By this time, skills are performed quicker and require less practice for accurate

performance.

Another concern for many researchers was how species learn to perform novel or adapted

patterns of various goal-directed behaviors (Reid, 2009). Many species have learned and

performed new sequences of behavior in order to gain reinforcement or reach some satisfying

outcome. These sequences were often more complex than simple units of stimulus-response

behavior supported by the chaining theory, evidence of the ability to learn heterogeneous

response sequences. Terrace (2005) suggested the simultaneous chaining procedure overcomes

the limitations of the chaining theory and can explain serial and ordinal learning in animals.

Terrace defined a simultaneous chain as a sequence in which all the choice points were presented

at the same time, providing the possibility to make both backward and forward mistakes by


choosing the wrong choice point at anytime during the sequence. The presence of multiple

choices simultaneously required a more complex behavioral pattern to be learned in order to

complete the sequence. The presence of more than one stimulus in a simultaneous chain

procedure led to the learning of serial order by learning and practicing the correct sequence. The

simultaneous chain procedure provided a theory that can apply to both humans and nonhumans

that goes beyond the explanation provided by the chaining theory for acquiring skills using serial

learning (Terrace, 2005).

While discriminative stimuli were once believed to set the occasion for a particular

response, more recent research indicates that stimuli have also produced patterns of behavior or

variability in behavioral responses. Behavioral variability is sensitive to the rate and frequency of

reinforcement (Denney & Neuringer, 1998). Pigeons were sensitive to the consequences of their

behaviors, which can also explain variability in their learned behaviors. Neuringer has exposed

rats, pigeons and people to multiple schedules that require response to be varied, whole

behavioral patterns based on one color stimulus. However, as seen in their pigeon study, it is

often unclear which external stimuli are controlling the behavior, whether it is the key color or

another stimulus control present (Denney & Neuringer, 1998).

Prior studies conducted in this lab have demonstrated the ability for rats and pigeons to

acquire skills and has led to further research concerning skill learning. Reid et al. (2011)

conducted a pigeon experiment to test skill acquisition using various conditions with the

presence or absence of guiding cues. A Follow-Red condition was the guiding light cue

condition and Both-Green as the no cue condition. Results of the experiment showed a decrease

in accuracy for the required left-right behavioral sequence when the condition switched from

Follow-Red to Both-Green. However, with further practice, the accuracy for the left-right (L-R)


sequence behavior improved in the Both-Green condition and quickly recovered in the guiding

cue condition. When the condition was switched to Reversed-Lights condition and the sequence

was also switched, the pigeons showed no trouble following the light cues and ignoring the L-R

sequence. The results indicate the pigeons were more prone to follow the guiding light cues,

failing to pay attention to the position cues indicating serial order in the L-R sequence. The

decrease in accuracy was expected, yet the results could not determine whether the left-right

sequence was actually learned or if the pigeons remained dependent on the guiding cues.

Figure 1 depicted the average results of the pigeon study conducted in 2011. The graph

showed that the pigeons were able to adjust rapidly to any condition involving guiding cues.

After a stable level of performance accuracy was reached in the guiding cues condition, accuracy

initially decreased during the second condition in which the guiding cues were absent. As the

results indicated, the pigeons were seemingly dependent on the guiding cues to direct their

behavior. The pigeons experienced the most difficulty when exposed to the conditions with no

guiding cues. These results suggested the guiding cues were more salient for the pigeons than

any other information because they had not associated the behavior with the no cues condition.

The drop in accuracy for the L-R sequence during the condition with no cues supported the

notion that the pigeons devoted more attention to the color of the guiding cues than the position

of the cues, and also explained the increase in accuracy once the guiding cue condition was re-

introduced.

The current study extended on the previous pigeon study conducted in 2011 to determine

what the subjects actually learn: the L-R sequence pattern or another behavior. To further test

skill acquisition, this experiment manipulated stimuli and conditions to determine how well the

pigeons learned the L-R sequence behavior in the presence and absence of their coach. We


wanted to determine how guiding cues and no cues affected learning. One set of pigeons was

exposed to the Follow Red condition seen in the previous study, and another set of pigeons was

exposed to a Red Green condition, a simultaneous chain procedure that required serial order

learning and knowledge of color cues in order to successfully complete. After the pigeons

reached a stable level of accuracy in the guiding cue condition, two pigeons in each of the

guiding cue conditions were placed in a condition without guiding cues in which all the key

lights were the same color, either both green or both red. The condition without guiding cues

provided information on how well the pigeons had known the L-R sequence without cues based

on the level of accuracy for the sequence.

Since the Follow Red condition was contingent on only the position of the guiding cues,

the pigeons in this condition were expected to reach higher levels of accuracy compared to

pigeons in the Red-Green condition. However, it was predicted the guiding cues would facilitate

quicker acquisition of the L-R sequence. The current study also predicted the absence of guiding

cues would result in a decrease for L-R accuracy in both conditions. A third prediction made in

the study was that practice of the L-R sequence in both the presence and absence of guiding cues

would improve overall accuracy for the sequence due to an internalization of the behavior. This

would indicate whether stimulus control changed during skill acquisition. Finally, it was also

predicted that the Follow-Red and Red-Green conditions required the pigeons to learn different

things, particularly since the Red-Green condition was more complex. Toward the end of the

study, an additional procedure was added to further assess the Follow Red and Red Green

conditions.

Method

Subjects


Eight experimentally naive homing pigeons (Columba livia), obtained from Double T

Farm (Glenwood, Iowa), served as experimental subjects. Supplementary mixed grain was

provided after daily sessions as necessary to maintain 85% of their free feeding body weights.

The pigeons were housed individually in standard cages with free access to water and grit under

natural lighting conditions in an environmentally controlled animal facility.

Apparatus

Four pigeon chambers were used. Two chambers were standard BRS-140 pigeon

chambers (24 cm wide, 35.5 cm long, and 29.5 cm high). The front panel was equipped with

three 2.5-cm response keys (Med Associates ENV-123 with tri-color displays) arranged

horizontally. Each key could be illuminated white, red, or green and was located 22 cm above

the floor. A force of approximately 0.15 N was necessary to operate each key. A food hopper

(BRS/LVE grain magazine) centered below the center key 7.5 cm from the floor, provided

access to mixed grain. The magazine was illuminated when food was presented. Each

experimental chamber was enclosed in a sound-attenuating box equipped with a 7-W 120-V

nightlight, located on the upper back wall of the box (behind the operant chamber), and a fan that

provided air circulation and masked extraneous noise.

The other two chambers were Gerbrands-style pigeon chambers (35 cm wide, 43 cm

long, and 36 cm high) were equipped with three 2.5 cm response keys (Med Associates ENV-

124 with multicolored displays) in a row 23 cm above the floor. Each key required a force of

approximately 0.15 N to operate. A food magazine (Lehigh Valley Electronics) was centered

below the center key 7.5 cm from the floor, and the magazine was illuminated when food was

presented. A 28-V house light (GE-1819) was located 6.5 cm above the center key. Ventilation


fans masked extraneous noises. All chambers contained a miniature color television camera

located at the top of the back wall of the chamber to monitor subjects from an adjacent room.

All operant chambers were controlled by a single Dell personal computer (Pentium 4)

programmed in MED-PC IV, which controlled all experimental conditions and recorded every

event and its time of occurrence with 10-ms resolution.

Procedure 1

All Conditions. Two independent variables were examined, guiding cues (Follow-Red

and Red-Green) and no cues (Both-Red and Both-Green). Birds were placed in the chamber and

presented with three keys, left, center, and right. Once a session began, the left and right key

lights would illuminate, and the pigeons would begin pecking the key. The center key was never

illuminated. In order to successfully complete the sequence, subjects were required to peck the

left key and then peck the right key. Once one key was pressed, the light on the key would

quickly turn off and on to indicate a successful key peck. Upon completing the sequence

correctly, the feeding dispenser would be available for 3s for the pigeons to receive access to

food as reinforcement. Then the birds experienced a 3s inter-trial interval before the next trial.

An incorrect sequence resulted in a 6s time out in which no keys were illuminated, and no access

to food was given. Sessions lasted a maximum of 45min or until 60 reinforcers were acquired.

The subjects were first divided into two groups trained on either the Follow-Red or Red-

Green guiding cues condition until they reached stability, defined as consistently above 80%

accuracy for five days. Once stability was reached, subjects were further divided and exposed to

either the Both-Red or Both-Green conditions for five sessions. This transition between the five

sessions of the guiding cues condition to the five sessions of the no cues condition was defined

as phase. Phase was the third independent variable tested, used to measure the increase in


accuracy over time. After completing the first phase, subjects were re-exposed to their original

guiding cues condition and repeated the procedure until four total phases had been completed.

By measuring the difference in accuracy within phases, accuracy for both the Guiding Cues and

No Cues conditions were tested. Furthermore, the change in accuracy over time between phases

tested any changes in stimulus control between Guiding Cues and Practice Cues.

Follow-Red. In the Follow-Red condition, the left key was illuminated red and the right

key illuminated green. Once a peck to either key was completed the keys briefly turned off and

the left key was illuminated green and the right key illuminated red. After completing the

sequence

Red-Green. The pigeons in the Red-Green condition were presented with the same initial

situation; the left key was illuminated red and the right key illuminated green. However, when

the pigeon pecked a key, the lights blinked off briefly, but did not change color.

Both-Green. In the Both-Green condition, both the left and right key were illuminated

green. After the pigeon pecked a key, the key lights turned off and were again illuminated Both-

Green.

Both-Red. The Both-Red condition was identical to the Both-Green condition except that

the keys were illuminated red instead of green.

Procedure 2

After completing four phases, subjects were re-exposed to their original Guiding Cues

condition one final time before being exposed to the Guiding Cues condition they had not

experienced before (Ex: Subjects trained in the Follow-Red condition were exposed to the Red-

Green condition and vice-versa). Following five sessions of the unfamiliar baseline, the subjects


were exposed to five sessions of the Both-White condition. This procedure tested whether or not

the pigeons in the different Guiding Cues conditions learned different information.

Both-White. The Both-White condition was identical to the Both-Red and Both-Green

conditions except that the keys were illuminated white when lit.

Results

Guiding Cues

The first step in this experiment was to test the hypothesis that guiding cues would affect

the learning of the L-R pecking sequence. Pigeons were placed in either the Follow-Red or Red-

Green guiding cues condition. The accuracy for pecking the L-R sequence in each session was

used to show learning. The birds were kept in this initial guiding cues condition until they

showed relatively strong mastery of the L-R sequence and were stable at that accuracy.

Follow-Red Condition. Four subjects learned the L-R sequence associated with the

Follow-Red guiding cues condition over 8-15 trials, averaging 9.75 sessions and achieving the

minimum of 80% L-R performance accuracy with stabilization over 5 consecutive days required

to change conditions. Sequence accuracy was measured using the number of trials in which the

L-R sequence occurred divided by the total number of trials. The results of these four pigeons

were placed in a graph. Figure 2 represents the accuracy of each pigeon in the Follow-Red

condition at completing the L-R pecking sequence across all sessions.

Red-Green Condition. The accuracy of each pigeon in the Red-Green condition at

completing the L-R pecking sequence across all sessions is shown in Figure 3. Four subjects

learned the L-R sequence associated with the Red-Green guiding cues condition over 14-22

trials, averaging 17.5 sessions and achieving the minimum of 80% correct response asymptote of

stabilization over 5 consecutive sessions required to change conditions.


These results suggest that the initial learning of the L-R sequence was faster for the birds

in the Follow-Red condition. They learned the sequence an average of 8 sessions sooner than the

Red-Green birds.

No Cues

Our next research question looked at the no cues condition and asked whether there was a

difference between Both-Green and Both-Red. The results from Figure 2 and Figure 3 show that

all the birds increased performance in the no cues condition throughout the experiment. In order

to better look at these results, we averaged the results from the Both-Green and Both-Red

pigeons in Follow-Red and Red-Green. These results are shown in Figure 4. The black dots

represent the average across all four pigeons in each condition. There is a difference seen

between the Both-Green and Both-Red birds in the Follow-Red condition but the overall trend of

learning is similar. The difference between the results of these two conditions is due to a lower

baseline for one of the Both-Red pigeons. Since the baseline was lower for these pigeons, the

focus of our results for all eight pigeons was on the drop in accuracy seen when the pigeons

switched from guiding cues to no-cues. The initial drop in accuracy on the first day of the no-

cues condition showed that there was not a difference between the Both-Green and Both-Red

conditions for all birds. The drop was found by subtracting the last day accuracy in the guiding

cues condition from the first day in the no cues condition. The data supports the conclusion that

there was no difference between the two no cues condition.

To highlight these results, we created a graph showing this drop for all conditions. That

graph is shown in Figure 5. The points on this graph represent the initial drop in accuracy from

the last day of the guiding cues condition to the no cues condition. The dotted line represents a

linear comparison between the two conditions which would result from no difference in the


Both-Green and Both-Red conditions. The solid dots represent the initial drop from the cues to

no cues condition across all four phases in the Follow-Red condition. The open circles represent

the data for the Red-Green birds. The farther away from the dotted line represents the stronger

the effect of one condition over the other on the results. The overall linear nature of the results

showed there was no difference between the Both-Green and Both-Red conditions.

Phase

The results from Figure 2 and Figure 3 can help show the effect of phase for all eight

pigeons. The question we are hoping to answer by looking at phase is whether there was learning

occurring across phases and how that learning was different for the two guiding cues conditions.

For the Follow-Red birds, each repetition of the Follow-Red to the no cues, Both-Red or Both-

Green, condition represented a phase. The no cues conditions used the same color lights on the

left and right keys. Thus this condition showed the ability of the pigeon to perform the L-R

sequence without external cues. Four phases were completed by each pigeon in the initial

procedure. A repeated measures ANOVA showed a significant main effect of phase for the birds

in the Both-Green condition [F (3,3) = 9.515, p = 0.048]. This result showed that the pigeons

improved their accuracy across the four phases. There was no significant main effect of phase for

the Both-Red condition. The results of pigeon 274 did not allow for a main effect to be seen in

the Both-Red condition or across all Follow-Red pigeons.

The same process was completed with the Red-Green pigeons. Each repetition of the

Red-Green to the no cues, Both-Red or Both-Green, condition represented a phase. Four phases

were completed by each pigeon in this condition. A repeated measures ANOVA showed there

was no significant main effect of phase for the birds in either the Both Green and Both Red

condition. Another repeated measures ANOVA was performed on all four pigeons in the Red-


Green condition that showed a significant main effect of phase [F (3,9) = 6.976, p = 0.010].

Figure 3 showed that each no-cues condition had one pigeon perform extremely well and one

that showed more difficulty across phases. This would result in no main effect of phase for the

no-cues conditions separately. The finding of a main effect across all phases showed that

accuracy did increase across the four phases. The first day in the no cues condition for each

phase showed an asymptote of learning across all the pigeons in this condition.

Figure 6 showed the initial drop in accuracy on the first day across all conditions in a bar

graph. The graph results show that the Follow-Red birds had a much higher drop between the

guiding cues and no-cues condition across all four phases than the Red-Green birds. The results

support the claim that the Red-Green birds were better at learning the L-R sequence than the

Follow-Red condition. The results from phase 1 are the most similar but the Red-Green birds still

performed better as seen by a smaller drop between conditions. The data from phases 2, 3, and 4

show a smaller drop in accuracy for the Red-Green birds. This smaller drop showed that the Red-

Green birds were closer to their initial baseline than the Follow-Red birds and suggested better

learning of the L-R sequence.

Procedure 2

The end of procedure 1 left us the question as to whether or not the pigeons learned

different things. This question inspired the addition procedure 2 to the end of our experiment.

The results from this procedure are shown in Figure 7. The pigeons were placed in procedure 2

where they would complete 15 more sessions. Each pigeon was first placed in their initial

learning condition, either Follow-Red or Red-Green, to re-establish baseline. For the next five

sessions, the pigeons were placed in the alternate guiding cues condition. After five sessions, the

pigeons were placed in the Both-White no-cues condition. The results show that the pigeons


easily re-established a baseline on their initial guiding cues condition. The transition to the

alternate guiding cues condition showed the initial drop was larger for the birds switching from

Follow-Red to Red Green. The Red-Green birds showed very little drop when switching to

Follow-Red and quickly improved back to baseline results. The data suggested that the Red-

Green condition is a more complex condition and is harder to learn than the Follow-Red

condition. After the initial drop in the alternate guiding cues condition, the pigeons showed a

steady increase in performance. The presence of lights acting as guiding cues allows for steady

and swift improvement. The Both-White condition showed that all pigeons had learned the L-R

sequence relatively well. Although the results are similar, the results show greater performance

accuracy for the Red-Green birds than the Follow-Red birds. The drop in performance for the

alternate condition and the Both-White condition suggest that the Red-Green birds were learning

something different than the Follow-Red birds. The Follow-Red birds performed at a lower rate

showing a reliance on the guiding cues provided by the lights. The Red-Green birds showed a

stronger independence from the guiding cues and higher rates of L-R performance accuracy.

Discussion

At the start of the present study, several questions about the nature of skill learning

existed. The data generated by the eight pigeons in the two groups of guiding cues conditions

tried to answer the specific questions of this experiment, but more general questions remained. In

general, the present experiment hoped to answer questions about how to accurately and

completely represent the complexity of information that animals can learn. Additionally, this

experiment hoped to move the current research in the direction of finding a complete and

accurate animal model that takes all of the information an animal can learn about a behavior

sequence and how they learn about that sequence. There are cognitive models in place for


humans, such as the three-stage cognitive model of skill acquisition set forth by Fitts (1964).

However, there are no current animal models in existence to adequately explain animal

cognition. Data collected before this study was conducted adds to the call for a more complete

animal model and will be discussed at the conclusion of the subsequent section.

As previously stated, there were several questions this study attempted to answer. First

was the effect of the presence of guiding cues on behavior. It was predicted that the presence of

guiding cues would facilitate the learning of the Left-Right (L-R) pecking sequence. In terms of

the present experiment, guiding cues act as a coach for the pigeons, teaching each bird to peck

left and then right in that order. Successful performance with this L-R sequence was considered

an indication of skill acquisition. The guiding cues are provided as a coach to help the pigeons

learn to peck left and then right so they are able to perform the behavior. The L-R performance

accuracy was expected to indicate which set of guiding cues, Follow-Red versus Red-Green, was

the better coach.

The second question addressed the effects of the absence of guiding cues on L-R

performance accuracy. It was predicted that the absence of the guiding cues would initially

decrease the accuracy of the L-R pecking sequence performance as a result of the absence of the

coach. During the no cues condition, the pigeons in the Follow-Red and Red-Green guiding cues

conditions were expected to practice the L-R pecking sequence without the coaching influence of

the guiding cues.

The third question addressed the whether the guiding cues and no cues conditions

produced a change in stimulus control. It was predicted that, with practice in the presence and the

absence of guiding cues, the L-R pecking sequence would improve over time as a result of the

internalization of the L-R pecking sequence. It was expected that, with practice, the pigeons


would internalize the L-R sequence and their performance accuracy would improve in both the

presence and absence of the guiding cues. Their demonstrated improvement would indicate

independence from the coaching influence and their knowledge of the L-R sequence.

The data collected in the experiment present several pieces of information that answer the

questions asked by this study. The question pertaining to the effects of guiding cues on behavior

will be answered first. Figures 2 and 3 demonstrated the effect of guiding cues on the

performance accuracy of the L-R behavior sequence in the guiding cues and in the no cues

conditions for both the Follow-Red and the Red-Green guiding cues groups. In Figure 2, the four

pigeons trained on the Follow-Red guiding cues showed a fast ascent to maximum levels of

accuracy in the first guiding cues condition. The Follow-Red pigeons performed the L-R

behavior sequence very well almost immediately in the presence of the guiding cues that only

required the following of the red light from the left key to the right key. However, L-R

performance accuracy fell very quickly in the first no cues condition. Only without the guidance

of the red key lights as a powerful coach and sufficient amounts of practice did the birds

eventually improve their L-R performance accuracy across the no cues conditions. The fact that

the birds performed at such a high level of accuracy in the Follow-Red guiding cues condition

and also recovered their L-R performance accuracy after exposure to the no cues condition

suggested that the guiding cues had an effect on the L-R performance accuracy.

Figure 3 showed an effect of guiding cues on the accuracy of the L-R behavior for the

Red-Green birds as well, but only in the initial learning of the pecking sequence. Due to the

difficulty of the Red-Green guiding cues condition as a result of less obvious coaching, this

group of birds took longer to reach the minimum 80% L-R performance accuracy. The effects of

the Red-Green guiding cues are seen throughout the remainder of the guiding and no cues


conditions in sustained levels of L-R performance accuracy. The Red-Green guiding cues may

have been a harder coach because less overt guidance was provided, but the less obvious coach

showed better L-R sequence knowledge later in the experiment with higher rates and more stable

performance accuracy across the guiding and no cues conditions. The effects of guiding cues are

thus shown in the Red-Green guiding cues group of birds as well.

The second question the present study attempted to examine was how L-R performance

accuracy in the absence of guiding cues would be affected. All but Figure 7 showed a similar

initial decrease in L-R performance accuracy upon first exposure to the no cues condition in both

the Follow-Red and Red-Green guiding cues groups. This drop was due to a lack of sufficient

practice with the L-R behavior sequence in the absence of the coach. This claim was supported

by the data in subsequent no cues practice sessions by the improvement in L-R performance

accuracy in both groups of pigeons.

Figures 4, 5, and 6 showed the effects of the no cues condition on the pigeons’ behavior

very well. In the first transition between the guiding and no cues conditions, both groups were

still very dependent on their coaches and showed this dependence in a dramatic drop in L-R

performance accuracy. Figure 5 only showed the drop between the first guiding and no cues

conditions, suggesting that more practice was needed to see a more accurate depiction of the

absence of the guiding cues on the L-R sequence performance in both groups of pigeons. Figures

4 and 6 showed the effects of the absence of the guiding cues across the experiment and

suggested a stronger effect of their absence for the Follow-Red group due to the ease of their task

and their coach.

Figures 4 and 5 showed a similar and equal drop in the L-R performance accuracy for

both groups of pigeons in the transition from the first guiding cues condition to the first no cues


condition. Gradual improvement in L-R performance accuracy in both the Follow-Red and in the

Red-Green guiding cues groups was observed in the no cues condition in Figure 4, but there is a

difference in the improvements between the no cues conditions among the groups. The learning

of the L-R behavior sequence can be inferred from the decrease in the drops between conditions

in performance accuracy over time between the groups of pigeons. However, the Red-Green

guiding cues group demonstrates a faster improvement in L-R performance accuracy in the no

cues conditions than the Follow-Red birds as shown in Figure 4. This data suggested more

support for the Red-Green guiding cues as being the better coach, translating to better learning

and performance among the pigeons in this group. For the Follow-Red group, it took until the

final no cues condition for them to demonstrate their highest performance accuracy across the no

cues conditions. Due to their having the easier coach, the no cues condition was more difficult

for them in terms of performing the L-R pecking sequence without their coach. The effect of the

no cues condition for the Follow-Red group was shown in their gradual ascent to L-R

performance accuracy in the no cues conditions than the Red-Green pigeons, as was evident in

Figure 4.

The pigeons trained in the Red-Green guiding cues condition demonstrated higher L-R

performance accuracy in the absence of guiding cues in the final no cues condition than the

Follow-Red birds, which was supported in Figures 2, 3, and 4. The data in these graphs showed

their first transitional drop in performance accuracy between the first guiding and no cues

conditions was equal to the Follow-Red birds, but the Red-Green guiding cues group learned to

perform the L-R pecking sequence at a higher rate than their counterparts with and without the

guiding cues. The quality of their coaching in the guiding cues condition surfaced in their


performance without the coach in the no cues conditions, suggesting there was an effect of the no

cues condition to direct behavior between the groups of birds.

The third question the present study addressed was the ability for the stimulus controlling

the performance of a behavior to change as learning does through practice. In the beginning of

the experiment, the guiding cues had a large effect on L-R performance accuracy. The data in

Figures 2 and 3 supported this claim, especially because of the visible differences between the L-

R performance in the guiding cues and the no cues conditions. The L-R performance accuracy in

the initial guiding cues conditions was substantially higher than the performance accuracy in the

no cues conditions for both the Follow-Red and the Red-Green groups of birds. As the conditions

progressed and the birds were exposed to the guiding cues and no cues conditions multiple times,

the L-R performance accuracy improved. As a result of the improvement in accuracy, it was

inferred that learning occurred. Having learned more about the L-R behavior sequence, each bird

depended less on the external coaching influence of the guiding cues and more on the internal

representation of the L-R behavior sequence. Thus, the stimuli that initially controlled their

behavior in the beginning of the experiment shifted from external control to internal control. The

pigeons had become the ones controlling their behavior instead of the presence versus the

absence of the guiding cues.

Figures 2, 3, and 4 showed evidence for the change in which stimuli controlled the

pigeons’ behavior as well. In each of these graphs, the decrease between transitions from guiding

cues to no cues over time with practice suggested that learning had occurred and the guiding cues

were not as important for the successful performance of the L-R pecking sequence. The birds in

both the Follow-Red and the Red-Green guiding cues conditions eventually shifted from an

external dependence on the guiding cues in order to know what to do to an internal dependence


that accurately directed their performance regardless of the presence or absence of the guiding

cues. Therefore, the stimuli controlling the birds’ behavior became the internal representation

rather than the external guiding cues. Additionally, Figure 6 showed the decrease in drops

between transitions from the guiding cues to the no cues conditions over time as practice

accumulated in both groups of birds. The Red-Green pigeons showed the change in stimulus

control very well in that their initial drop in L-R performance accuracy was equal to that of the

Follow-Red birds, but their L-R performance accuracy drops between the guiding and no cues

conditions became smaller over time much faster than the Follow-Red birds. This data suggested

that the Red-Green guiding cues were a better coach for the speed of internalization for the L-R

pecking sequence.

After the completion of the first procedure in the present experiment, another question

became evident. The data for the birds trained in the Follow-Red and Red-Green guiding cues

conditions suggested a difference in the kind of information learned about the L-R behavior

sequence. It seemed that the birds in the Follow-Red guiding cues condition performed at a lower

degree of L-R performance accuracy without influence from their guiding cues while the Red-

Green guiding cues group seemed to perform the L-R sequence without a great deal of trouble. It

was predicted that the strength of the saliency of the guiding cues hindered the learning of the L-

R sequence in the no cues condition for the Follow-Red birds, resulting in them learning less

about the L-R sequence and more about the colors presented. In terms of the Red-Green guiding

cues group, it was predicted that they learned information about the colors and the serial order

that allowed them to learn the L-R sequence to a higher degree and perform more accurately

without the guiding cues.


This additional question that inspired the second procedure came about because it seemed

the two groups of pigeons had learned different things about the L-R sequence. Earlier in the

experiment, the drops in performance accuracy in Figures 4, 5, and 6 suggested that both groups

of pigeons trained with different guiding cues had not learned the sequence. Both groups of

pigeons demonstrated equal drops in L-R performance accuracy between the initial guiding cues

condition and the initial no cues condition. However, the data from Figures 2 and 3 suggested a

divergence between the mastery levels of the L-R behavior sequence between the Follow-Red

and the Red-Green guiding cues pigeon groups. The divergence of performance accuracy in the

no cues conditions demonstrated in all figures suggested additional data should be gathered to

address this question.

The data from the second procedure in the present experiment is displayed in Figure 7.

The pigeons initially trained in the Red-Green guiding cues condition performed all subsequent

conditions in the second procedure with higher L-R accuracy than the birds initially trained in

the Follow-Red guiding cues condition. An explanation for this phenomenon is that the Red-

Green guiding cues condition was a more complex task to learn than simply following a key light

that is highly salient in its red color and its physical movement from left to right during the

session. The birds trained in the Red-Green guiding cues condition did not have a coach

imposing on their learning and had to learn to peck red first on the left and green second on the

right. Knowledge of serial order was required for Red-Green birds to be successful in the guiding

cues condition and in the no cues condition, whereas the Follow-Red birds only needed

knowledge of serial order in the no cues conditions. Thus, pigeons in the Red-Green guiding

cues condition had to learn information about what color to peck at what point and kept track of

what they had already pecked to know what came next in the response sequence. The pigeons in


the Follow-Red guiding cues condition merely had to follow their coach and experienced trouble

in producing the correct behavior sequence when their coach was absent. This explains their fast

ascent to accuracy in the guiding cues condition and their gradual climb in L-R performance

accuracy in the no cues condition.

As additional support for the two groups of birds learning different things, the alternative

guiding cues condition and the final no cues condition showed interesting information as to what

the pigeons learned. In the alternative guiding cues condition, each bird was switched to the

guiding cues they had not seen before in the first procedure. Figure 7 showed that the birds

originally trained on Follow-Red guiding cues performed worse and needed 2 or 3 of the 5 total

sessions to learn what to do in their new surroundings. The birds trained on the Red-Green

guiding cues performed much better when switched to the Follow-Red guiding cues as a result of

it being an easier task and their having learned the L-R sequence under a tougher coach. In the

final no cues condition, both lights were white and was something no bird in the experiment had

seen before. Performance accuracy during this Both-White condition would suggest which birds

had truly learned the L-R behavior.

Consistent with the previously demonstrated trend from the previous procedure in this

experiment, the birds originally trained on the Red-Green guiding cues performed the sequence

with slightly higher session values. The birds originally trained on the Follow-Red guiding cues

experienced trouble in the Red-Green guiding cues condition, but seemed to benefit from the

minimally involved coaching in that condition. Even with their improvement within the second

procedure, the birds originally trained on Follow-Red did not perform as accurately in the Both-

White condition as the Red-Green birds.


This study aimed to determine what information affected the acquisition of the L-R

pecking behavior. Results found that practice is needed to internalize the demands of a skill and

that an easier coach is not always the best for sustained learning. The two groups of pigeons were

able to demonstrate learning of the L-R pecking sequence regardless of their struggles in the

guiding and no cues conditions. The fact that the pigeons generalized learned behaviors from

previous rewarded experiences supports the findings in the present study that different factors

within the environment control behavior at different points. Previous studies have demonstrated

that pigeons are just one type of animal that can take what they have learned from practice and

apply it to uncertain environments, which is a potential explanation for exactly how learning

occurred and continued to improve in the present study (Weismann, Wasserman, Dodd, &

Larew, 1980). The data included in this manuscript suggested that some coaching or guidance is

needed in the initial learning of a skill, but the opportunity to practice independent of that

guidance is invaluable to learning and performance in current and future uncertain environments.

The results in this experiment also support other learning theories, such as serial order

and chaining theory. According to Terrace (2005), an animal’s ability to keep track of what

actions they have already performed is essential to learning more complex action sequences

containing many parts. In this study, the pigeons in both groups needed to learn serial order to

remember to peck left first and then right in the presence of different colors. In addition to

learning to peck left and right, the birds had to learn that the presence or absence of certain

colors still required a left and then right peck. Therefore, they had to possess knowledge about

the colors to help them remember what to do and kept track of what had already been pecked as

well as what was required next. The birds demonstrated their ability to learn about the colors and

serial order simultaneously, which suggested support for Terrace’s simultaneous chaining theory


that allows animals to learn two or more things about a behavior sequence at once (Terrace,

2005).

Future studies should determine a few things based on the information presented in this

manuscript. First, it has been mentioned in earlier sections of this document that a better model

to represent the abilities of animal cognition is needed. The Rescorla-Wagner model seems to be

the closest currently existing model to estimating the associative value of each stimulus involved

in a behavior sequence (Rescorla-Wagner, 1972). The model suggests that the learning of one

stimulus can reach a maximum level of 100% associative strength, but this maximum level

associated with a particular stimulus does not leave room for the other things that animals can

learn about a behavioral association. The present study demonstrated that pigeons are just one

species that can learn more than one type of association about a behavior sequence. The Red-

Green birds showed learning about color and positioning at the conclusion of the first

experiment, but the Follow-Red birds also demonstrated that they could learn the same

information relatively well with the right kind of coach. Therefore, the Rescorla-Wagner model

does not account for everything an animal can learn about a behavioral sequence. A more

inclusive animal model that acknowledges the balance of stimulus competition and how the

animal’s representation of those stimuli changes is needed.

In addition, the present experiment did not have adequate time to determine how much

practice is needed to translate to autonomy in performing a given behavior or skill. The Follow-

Red birds were able to demonstrate that they had learned the L-R pecking sequence relatively

well by the end of both procedures in this experiment, but the present study would like to inspire

future studies to look more into the amount of time it would take to form L-R pecking behavior

that is completely independent of guiding versus no cues. It would be interesting to determine if


the L-R pecking behavior could become autonomous and how much time would be required to

do this.

In conclusion, there is a very simple message to take away from the findings presented

here. This study demonstrated that some guidance is needed when initially learning a skill, but

there is merit in the saying that “practice makes perfect.” A balance between having just enough

guidance to give direction and structure to practicing a skill independently so the individual is

learning the skill by performing it instead of having things done for them is the key to effective

learning and sustained success.


References

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Reid, A.K. (2009). Resistance to change within heterogeneous response sequences. Journal of

Experimental Psychology: Animal Behavior Processes, 35(3), 293-311.

Reid, A. K., Nill, C. A., & Getz, B. R. (2010). Changes in stimulus control during guided skill

learning in rats. Behavioural Processes, 84, 511-515.

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Cognitive Science, 9 (4), 202-210.

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Figure 1. The figure depicts the average results for the previous pigeon study conducted in 2011.

The data represents the results for both the guiding cues and no cues condition, Both-Green.

Pigeons were exposed to a guiding cues condition, no cues condition, and a reversed guiding

cues condition.


Figure 2. This figure represents the L-R sequence accuracy for the pigeons in the Follow Red

condition. The data represent the four phases that were performed using each pigeon. A phase

included the Follow Red and the five days in the no cue, Both Red or Both Green, condition.


Figure 3. This figure represents the L-R sequence accuracy for the pigeons in the Red Green

condition. The data represent the four phases that were performed using each pigeon. A phase

included the Red Green and the five days in the no cue, Both Red or Both Green, condition.


Figure 4. This figure represents the average L-R sequence accuracy for the pigeons in each

condition. The top graph shows the results from the birds in the Follow Red condition and the

bottom graph shows the results from the Red Green birds. The red dots represent the average of

the two birds in each Follow Red and Red Green condition that were in the Both Red, no cues

condition. The green dots represent those birds in the Both Green condition.


Figure 5. This figure represents the linear regression seen when comparing the drop in accuracy

of the L-R sequence on the first day of the no cues condition. The average drop in accuracy of

the 2 birds in each Both Red condition were compared with the average drop in the Both Green

condition across the four phases. The black dots represent the average of the pigeon’s initial drop

in accuracy for the Follow Red birds. The open dots represent the drop for the Red Green birds.


Figure 6. This figure represents the drop in L-R accuracy for the pigeons in each condition

across all four phases. The top graph shows the results from the birds in the Follow Red

condition and the bottom graph shows the results from the Red Green birds. The green bars

represent the initial drop in accuracy for the Both Green birds and the red bars represent the Both

Red birds.


Figure 7. This figure shows the results from all 8 pigeons across the last 15 days of the

experiment. The pigeons were first placed in their initial learning condition to reestablish the

baseline. They were then placed in the alternate learning condition for five sessions. The birds

were then placed in the Both White, no cues condition for the last five sessions.

a research thesis submitted in partial fulfillment of the ...webs.wofford.edu › reidak › pubs...

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