EXAMPLE QUESTIONS FOR THE FIRSTTERM LABS
Lab 1: Motor Skills (Mirror Tracing)
In the Motor Skills Lab we identified two major sources of error that any experimental
design must take into account. Describe how the effects of these sources of error were
minimized in our experiment.
Progressive error was minimized by counterbalancing, a technique which changes the
order of trials (ABBA) so that no one condition benefits from the practice of previous
trials. For example, in the dart board example, in order to prove that blowing on one’s
hand improves throwing accuracy, one must ensure that the control and experimental
trials are "mixed up", so to speak. If all the trials for one condition follow all the trials
for another condition, the second will benefit from all the previous trial practice.
Random error was minimized by calculating means to eliminate extreme scores which
could skew a data plot. For example, in the golf ball example, an average distance was
taken of all the balls hit, rather than an individual score which may not be
representative of the subject’s true ability.
Lab 2: Laterality
Why are subjects asked to stare at a fixation point during the hemispheric
specialization task? How is this critical for measuring the degree of lateralized
Because of the structure of the visual neural pathways, information presented to the
right visual field is processed by the left hemisphere of the brain, and vice versa.
Subjects must stare at a central fixation point so that the stimuli can be presented on
either side. This ensures that the correct stimulus will be administered to the appropriate
visual field. Some cognitive functions are lateralized; therefore, accuracy will be higher
when stimuli are presented in the visual field connected to the appropriate hemisphere.
In order to more accurately measure the degree of lateralization, we must be able to
present different types of stimuli to different hemispheres. If one stares directly at the
stimulus, both hemispheres will process the information, and assessment of laterality
becomes impossible. Lab 3: Polygraph & Pavlovian/Classical Conditioning
Describe the design of our classical conditioning experiment and the procedures
adopted to measure the size of the GSR.
Apre-test/post-test design was used to measure the effect of classically conditioning a
subject to respond to a two-second tone (Conditioned Stimulus — CS) as though it
were a one-second shock (Unconditioned Stimulus — UCS), by means of delay
conditioning (one-second delay). The change in the size of the galvanic skin response
(GSR) was measured after four training trials, and again after extinction trials. There
were three pre-tests: the tone alone to measure orienting response, the tone alone again
to observe habituation and the shock alone to measure the Unconditioned Response
(UCR).Apost-test was done to measure the GSR to tone (CS) alone after four CS-UCS
pairings. GSR was measured again after the fifth and tenth extinction trials. In order to
measure the GSR, the screen was paused and a rectangle was drawn to measure latency
of the response from the onset of the stimulus to the start of the response. Then, a
second rectangle was drawn to measure the amplitude and duration of the response by
"framing the GSR valley".
Lab 4: Sniffy & Operant Conditioning on Continuous Reinforcement Schedules (CRF)
Draw a diagram illustrating the cumulative record when conditioning has been
completed followed by extinction. Make sure you label the points at which the learning
and extinction criteria have been met. In two brief sentences, define these criteria. The learning criterion was two pen resets on the cumulative record, or 150 bar presses.
The criterion for extinction was the end of the first five-minute period containing fewer
than three bar presses.
Lab 5: Sniffy & Partial Reinforcement Schedules (PRF)
Describe the "Johnny B. Good" example to illustrate the advantages and disadvantages
of CRF and PRF reinforcement schedules.
This example suggests a "Johnny B. Rotten" in an elementary school classroom who is
disruptive to the learning of other students. The teacher begins a process of continuous
reinforcement (CRF) whereby she praises every positive thing that Johnny does. Johnny
quickly learns that good behaviour will be rewarded, so he performs it more and more
often. However, the teacher must eventually focus her attention on the other students in
the class and Johnny will no longer receive the reinforcement he seeks. His good
behaviour was easily conditioned using a CRF schedule (advantage), but will quickly
extinguish (disadvantage) in the absence of positive reinforcement. On the other hand,
if the teacher continues reinforcing Johnny, but gradually reduces the frequency (i.e., a
partial reinforcement (PRF) schedule), Johnny will learn that it is best to be well-
behaved all the time. Behaviour on a PRF schedule is more difficult to condition
(disadvantage), but will have a more long-lasting effect (advantage).
Lab 6: Decision Time
Describe the logic of the subtractive technique and how we used it to measure the
decision time in the light bulb reaction time task.
The subtractive technique requires two tasks that are identical in all processing steps
except one. The task with the extra step should have longer reaction times (RT).
Therefore, the difference in the two task RTs should be an estimate of the time for the
extra step. In the Decision Time lab, the subtractive technique was used to estimate the
decision time required for a choice task, compared to a simple task. The simple task
(one light bulb flashes, push a key) required no decision, but merely the encoding,
comparison, and response stages of processing. The choice task (one of two bulbs
flashes, push appropriate key) required subjects to encode, compare, DECIDE and,
finally, respond. By subtracting the Simple RT from the Choice RT, the remaining time
is that of the decision stage of processing. EXAMPLE QUESTIONS FOR THE SECOND TERM LABS
Describe the component skills involved in reading comprehension.
Reading and understanding written text involves multiple processes. Proficiency in
reading comprehension comes from the successful interaction of different cognitive
skills. Before one can apply the component skills of reading comprehension, one must
first possess sufficient language and problem solving skills, and good memory.
Language skills involve lexical recognition of words in the text, semantic understanding
of their meaning, and syntactic knowledge of how those words can be correctly
combined and chained together in a sentence. Problem solving skills require making
inferences and learning from the text. Both a good short-term and long-term memory
also serve as the foundation upon which to lay the building blocks of solid reading
comprehension. With those