Demystifying Research for Medical and Healthcare Students. John L. Anderson
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When placed in a shuttle box, an experimentally naïve dog, at the onset of the first electric shock, runs frantically about until it accidentally scrambles over the barrier and escapes the shock. On the next trial, the dog, running frantically, crosses the barrier more quickly than on the preceding trial; within a few trials it becomes very efficient at escaping, and soon learns to avoid shock altogether. After about fifty trials the dog becomes nonchalant and stands in front of the barrier; at the onset of the signal for shock it leaps gracefully across and never gets shocked again.
A dog that had first been given inescapable shock showed a strikingly different pattern. This dog's first reactions to shock in the shuttle box were much the same as of a naïve dog; it ran about frantically for about thirty seconds. But then it stopped moving; to our surprise, it lay down and quietly whined. After one minute of this we turned the shock off; the dog had failed to cross the barrier and had not escaped from shock. On the next trial, the dog did it again; at first it struggled a bit, and then, after a few seconds, it seemed to give up and to accept the shock passively. On all succeeding trials, the dog failed to escape. This is the paradigmatic learned‐helplessness finding. (Seligman, 1975).
FIGURE 2.5 Shuttlebox design.
Seligman demonstrated from this and later work on human subject that learned helplessness saps the motivation to initiate responses; disrupts the ability to learn; and produces emotional disturbance. That is, it has three levels of effect:
motivational
cognitive
emotional.
He went on to show how this effected people in real life and that this could even be implicated in depression and death. Read his book Learned Helplessness: On Depression, Development, and Death (1975); in addition to being educational, it is a thoroughly good read!
Don Hiroto (Hiroto 1974; Hiroto and Seligman 1974) worked on learned helplessness research in humans – using the universally accepted subjects: university students. Now, you can't put humans into shuttle‐boxes, they are too unwieldy and dangerous. But they designed a ‘finger shuttle box’. This was a small box with two compartments into which the research subject could insert her/his finger. There was a low barrier in the middle and the subjects could move their fingers from one side to the other. Another approach was to use a four‐button board. This was a simple board with four buttons, a green light (to indicate success), and a red light (to indicate failure). Pushing any button four times made the noise stop immediately in the ‘control’ group, but not if they were in the ‘helpless’ group when no amount of button pushing could stop the noise. He used a triadic design – with subjects being randomly assigned to one of three groups. An escape group were given loud noise which could be turned off by pushing a button. A yoked group got the same loud noise as the escape group, but they had no control over it. The third group got no noise. Subjects in a yoked group are linked to the subjects in the experimental group, but have no control over the stimuli they are given. Next, all were taken to a finger shuttle box and were exposed to loud noise. They could escape the noise by moving their finger from one compartment of the box to the other. The escape group and the no‐noise groups easily learned to escape the noise by ‘shuttling’ their fingers. The yoked group, however, failed to escape and avoid the noise: ‘Most sat passively and accepted the adverse noise’.
Note the sophistication of this design. Both the experimental group and the yoked group got exactly the same amount of the stressor (noise). The only difference was that the experimental group could control the situation – the yoked group could not. And the control group were not exposed to the stressor at all. Thus, any differences between the experimental group and the yoked control group could not be attributed to different exposures to the stressor. And the no‐noise control group acted as a group who received no stressor – that is, they acted as a group to check for any Hawthorne Effect!
Note about Giving Electric Shocks to Student Subjects in Research
It used to be widely accepted that low‐level electrical shocks which were painful, but did not cause actual damage, were permissible in research studies. When I started studying Psychology at Aberdeen, the former professor had been very much into research on learning. Legend has it that he gave his research subjects higher and higher levels of electric shocks in his experiments, until they began to refuse to take part in his research – even though it meant having to fail to meet the course requirements to take part in at least three experiments! So research which involved giving electric shocks to subjects was stopped.
Seligman's work developed further to use the four‐button board with a green light and a red light. The green light signalled success and the red light signalled failure after each burst of the noise. Twenty sets of white noise at 110 dB in 30 second bursts were the aversive stimuli. Students were allocated to an experimental group and a control group. All subjects were instructed that by pushing the buttons in the correct sequence they might stop the noise. If they got it right, the noise would stop and the green light would come on. If they did not get it right, the noise would not stop and the red light would come on. In the experimental group, pushing any button four times would stop the noise and the green light would come on to signal success. In the (helpless) control group, no matter which button was pushed in any sequence or in any number of times, the noise would not stop and the red light would come on to signal failure. After the trial, subjects were tested on simple cognitive tests – anagram solving and arithmetic tasks. Those in the experimental group did better than those in the helpless/control group at solving the tasks. In addition, those in the helpless/control group seemed to lose heart and give up trying to solve the tasks more than those in the experimental situation. He noted that learned helplessness, sapped the motivation to try; it had cognitive impairments, and it had affective (emotional) impairments.
Example 2: My Own Experiment
I have always been very impressed by Martin Seligman's work and was eager to do my own research on helplessness. So, when I was at the University of Hong Kong in the 1980s, I informed my staff in the Behavioural Sciences Unit in the Faculty of Medicine of my interests. Within a month, half of them had started doing their own work to replicate Seligman and Hiroto's work! My interests were in people's lifelong exposures to helplessness and how these might contribute to helpless characteristics – with the possible implications for survival from cardiovascular diseases and cancers. So, I set out on my quest. I was on ‘long leave’ in London. I had the necessary equipment built – a computerised control box, a set of headphones, and a four‐button board. I made announcements to medical students and asked for volunteers for my pilot study. I vividly remember my first two subjects.
The first was in the control group – no matter what buttons he pressed, or in what order, or how many times, the noise could not be turned off and the red light would come on to signify failure. I remember him on the last of the 20 trials; he was bashing away at the buttons, frantically trying to find the correct sequence. Afterwards, I interviewed him about his life history of feeling in control or helpless. He was what you could call a ‘straight