Psychology the Nervous System

Assignment 3 Written Essay Questions 1. a) We are able to experience different types of sensations because our nervous system encodes messages. German physiologist Johannes Muller in his doctrine of specific nerve energies described a kind of code which is anatomical. In his doctrine, Muller explains that different sensory modalities exist because signals received by the sense organs stimulate different nerve pathways that lead to different areas of the brain. For example, when the ear receives signals, these signals cause impulses to travel along the auditory nerve to the auditory cortex.And signals from the eye cause impulses to travel along the optic nerve to the visual cortex. Because of these anatomical differences, light and sound produce different sensations. b) The code in the nervous system that helps explain why a pinprick and kiss feel different is known as functional. These codes rely on the fact that sensory receptors and neurons fire or are inhibited from firing, only i n the presence of specific kinds of stimuli. Functional encoding may occur all along a sensory route, starting in the sense organs and ending in the brain. 2.The lens of an eye operates differently from a camera, that just like a camera, the eye registers spots of light and dark, but neurons in the visual system build up a picture of the world by detecting meaningful features. The eye doesn’t passively record the external world, like a camera, ganglion cells and neurons in the thalamus of the brain respond to simple features in the environment, such as spots of light and dark. The existence of a specialized face module in the brain, explains why a person with brain damage may continue to recognize faces, after losing the ability to recognize other objects. . These units which were named after Alexander Graham Bell were called decibels (dB). Each decibel is 1/10 of a bel. Using decibels, they can be used to determine sound intensity, intensity of a wave’s pressure. Huma ns have an average absolute threshold of hearing of zero decibels and all decibels are not equally distant. For example, in my own environment, in my living room there is a 40decibel sound, my refrigerator and the light traffic from my window has about 50 decibels of sound.Everyday noises that may be hazardous to hearing could be rock concerts, deafening bars, stereos that are often played on full blast. In addition to that, noisy home appliances, lawn mowers and heavy city traffic also are hazardous to our ears. 4. If you were to inhale vapour from a rose, your receptors for smell have specialized neurons embedded in a tiny patch of mucous membrane in the upper part of the nasal passage. Millions of receptors in each nasal cavity respond to chemical molecules in the air.So when you inhale vapour from a rose, you’re pulling these molecules into the nasal cavity and can also enter from the mouth. These molecules then trigger responses in the receptors that produce that of fres h roses. From there, signals from the receptors are carried to the brain’s olfactory bulb by the olfactory nerve. And from the olfactory bulb, they travel to a higher region of the brain. 5. The basic concept of the gate- control theory, states the experience of pain depends on when pain impulses can get past a ‘’gate’’ in the spinal cord.The gate is a pattern of neural activity that blocks pain messages coming from the skin, muscles and internal organs or lets those signals through. Most of the time this gate is kept shut by impulses coming into the spinal cord from large fibres that respond to pressure or by signals coming down from the brain itself. However, when body tissue is injured, the large fibres are damaged and the smaller fibres open the gate. Once the gate is open, pain messages reach the brain unchecked. However, the theory doesn’t explain phantom pain, the pain from an amputated limb or organ that a person continues to feel aft er surgery.Melzack explains, even though there are no nerve impulses for the spinal cord gate to block or let through, the brain not only responds to incoming signals from sensory nerves but is also capable of generating pain entirely on its own. An extensive matrix of neurons in the brain gives us the sense of our own bodies and body parts. Pain results when this matrix produces an abnormal pattern of activity, as a result of memories, emotions, expectations or signals from various brain centres and not just from signals from peripheral nerves.Because of the lack of sensory stimulation or a person’s efforts to move a nonexistent limb, abnormal patterns may arise, resulting in phantom pain. 6. a) The role stimulus generalization plays in this problem is where mental images of the sights and smells of the clinic can become conditioned stimuli for nausea, aside from the nurse’s uniform, smell of rubbing alcohol or the waiting room. b) High order conditioning can be illus trated in this problem of vomiting and nausea where a patient who drank lemon –lime Kool-Aid before their therapy sessions developed anxiety disorders.They continued to feel anxious even when the drink was offered in their homes rather than at the clinic. c) Classical conditioning could help patients reduce pain and anxiety through the use of placebos. For example the use of pills and injections that have no active ingredients or treatments that have no direct physical effect on the problem. The bigger and more impressive the placebos are, the stronger their psychological effects are. 7. The evidence shows that punishments are effective when they are carried out immediately.As shown in the studies of criminal records of Danish men, punishments were effective in deterring young criminals from repeating their offences. After examining repeat arrests through the age of 26, punishment reduced rates of subsequent arrests for both minors and serious crimes. However, recidivism stil l remained fairly high. Other studies have indicated that the severity of punishment made no difference, in that fines and probation were just as effective as jail time. The consistency of the punishment is what matters most.For example, when law breakers get away with their crimes, their behaviour is intermittently reinforced and becomes resistant to extinction. Speeding tickets are another example of when you receive punishments. Even though the use of photo radar systems is useful for catching all speeders or reduces speeding, it doesn’t eliminate speeding entirely. As mentioned before, punishments are most effective in the period immediately following its delivery. This would explain when police officers supervise the speed traps; they are more effective since the punishment is given out immediately.However, when photo radars catch you, you have to wait for several weeks to receive the ticket. Laboratory and field studies find that punishments fail in everyday life, in sc hools, families and workplaces because of six drawbacks. The first is that people often administer the punishment inappropriately or mindlessly. People swing in a blind rage or shout things they don’t mean and when people aren’t angry, they misunderstand the proper application of punishment. Secondly, the recipient of punishment often responds with anxiety, fear or rage. Negative emotional reactions can create more problems than the punishment solves.For example, a teenager who has been severely punished may strike back or run away. Children, who have been punished physically in childhood, risk at being in depression, having low self-esteem, violent behaviour and many other problems. Third, depending on the presence of the punishing person or circumstances, the effectiveness of the punishment is often temporary. When a police officer is around at a park, you wouldn’t dare littering but if the police officer isn’t around then you wouldn’t be as afra id of littering. Forth, most behaviour is hard to punish immediately.For example, while you’re at work, your children eat all the deserts that were for tonight’s party, but you don’t punish them till after work, the punishment is no good. You children’s behaviour would have been reinforced by all those deserts. Fifth, punishments express little information, in that punishments may tell the recipient what not to do, but doesn’t communicate what the person should do. For example yelling at a student who learns slowly, won’t teach him/her to learn faster. Sixth, an action intended to punish may instead be reinforcing because it brings attention.For example, in the classroom, students enjoy when teachers yell at them in front of their classmates, putting them in the limelight. Often rewarding the student’s misbehaviour they are trying to remove. 8. a) Fixed Interval b) Variable Interval c) Variable Ratio d) Fixed Ratio Take a Long look 1. What is meant by the term â€Å"form perception†? Form perception means when an infant can or can’t respond to stimuli as shape, pattern , size or solidity. Thus they can see or can’t perceive form. 2. Why is the â€Å"preferential-looking† method of studying infants likened to a biologist’s use of a microscope?This method is similar to that of a biologist’s use of a microscope because this method is one of the first tools researchers turn to when they want to study how babies think. The method literally opened the doors to understanding the minds of infants. 3. What patterns were the babies in Fantz’s studies least interested in looking at? The patterns the babies were least interested in were the shapes that were just plain with no complexity. The least interesting shape for the infants was the square with no designs or complexity inside the square. 4.A preference for looking at faces is said to â€Å"set the stage for an infantâ €™s future survival and growth† (p. 41). Suggest two areas of learning that an infant’s attention to faces might facilitate. Two areas of learning that an infant’s attention to faces might facilitate are innate and primitive knowledge. The innate knowledge of the environment is shown by the infant’s interest in the kinds of forms that will later aid in object recognition, social responsiveness and spatial orientation. The primitive knowledge help provide an accumulation of knowledge through experience. 5.The early psychologist William James thought that the world for babies was a â€Å"blooming buzzing confusion† (see page 211 of the course text). Do Fantz’s findings support this statement? Explain. Fantz’s findings pointed out infants, regardless of age, can demonstrate that basic form perception is present at birth and ruling out a learning or developmental factor. Meaning that, babies have some kind of understanding of the diffe rent patterns and forms that are presented to them. This is how they are able to differentiate between faces, their mothers face or a stranger’s face. 6.Imagine you have been hired by a toymaker. Using Fantz’s findings describe your design for an infant toy or crib mobile. Using Fantz’s findings, I would create a toy that would have detailed patterns and include pictures or objects of faces of people or similar to those of people. Thus, I would create a toy with a face similar to that of humans and cover their body with items of great complexity, for example, a bull’s eye or a checkers board type of pattern. You would be able to place this toy over the infant in the crib, which should keep the infant entertained for many hours.Watch out for the Visual Cliff 1. What is meant by the statement that Gibson and Walk take a nativist position on the topic of depth perception? Both Gibson and Walk believed that depth perception and the avoidance of a drop-off app ear automatically as part of our original biological equipment and has nothing to do with experience. On the other hand, empiricists argue that these abilities are learned and aren’t biologically hard wired in us. 2. Write a one-paragraph summary of what Gibson and Walk discovered from their visual cliff studies with infants.Gibson and Walk had 36 infants for this study between ages 6 and 14 months with their mothers participating in the study. Nine of infants refused to move at all off the center of the board, which wasn’t explained by the researchers, but perhaps infant stubbornness. However, the other 27 infants crawled off the board and crossed the glass when called by their mothers on the shallow side of the table. Only 3 of the infants crept with hesitation off the brink of the visual cliff when called by their mothers from the deep side.When the infants were called from the cliff side by their mothers, most of the infants either crawled away from their mother on the shallow side or cried in frustration at being unable to reach their mothers without ‘’ falling off the cliff’’. The infants would often peer down through the class of the deep side and then back away or pat the glass with their hands, but would refuse to cross. After these results, it was difficult to prove that human’s ability to perceive depth is innate rather than learned because all the infants had at least 6 months of life experience to learn about depth through trial and error. . What did Gibson and Walk discover about depth perception in young animals? Gibson and Walk discovered that the ability of various animals to perceive depth developed in relation to when the species need such a skill for their survival. For example, within 24 hours of age, baby chickens never made the mistake stepping off into the deep side while looking for food. Kids and lambs response was the same as the baby chickens, which indicted the visual sense was in com plete control and the animals ability to feel the solidity of the glass on the deep side had no effect on the response.The rats were different from the others, as they didn’t show any preference for the shallow or deep side of the table. This could be explained by the fact that rats locate food by smell and doesn’t depend very much on its vision, but moves around using cues from the stiff whiskers on its nose. 4. Describe how Gibson and Walk use evolutionary theory to explain their infant and animal findings on depth perception. Gibson and Walk used evolutionary theory to explain that all animals that are to survive need to develop the ability to perceive depth by the time they able to move independently.For humans, this doesn’t occur until about 6 months of age and for chickens and goats it’s immediately. For dogs, rats and cats it’s about 4 weeks. Thus, this ability is inborn because to learn through trial and error would cause many potential fat al accidents. 5. Give one example of a finding that suggests depth perception has a learned component. A later study placed younger infants, ages 2 to 5 months, on the glass over the deep side of the visual cliff. The infants showed a decrease in heart rate, a sign of interest and not fear.This had indicated that the younger infants had not yet learned to fear the drop off and would learn the avoidance behaviour later on in life. 6. How has social referencing been found to impact youngsters' behaviour when faced with a visual cliff? In the Gibson and Walk study, when the mother had been instructed to maintain an expression of fear on her face, the infants refused to crawl any further on the table. However, when the infants saw their mothers looking happy, they checked the deep side again and crawled across.But when the drop-off was made flat, the infants did not check with their mothers before crawling across. Knock Wood 1. Why is Skinner referred to as a radical behaviourist? Skinn er is referred to as a radical behaviourist because he believed that all behaviours are ultimately learned, are controlled by the relationships between the situation that immediately precedes the behaviour and the consequences that directly follow it. This includes behaviours that are public or external, private and events such as feelings and thoughts.He believed that private behaviours are difficult to study, but acknowledged we all have our own subjective experience of these behaviours. However, he didn’t view internal events, such as thoughts and emotions, as causes of behaviour but rather as a part of the mix of the environment. 2. What is a Skinner box? How was the food dispenser set up for the pigeons in this study? Refer back to your text. What type of reinforcement schedule is this? The Skinner box consists of a box or cage that is empty except for a tray or dish into which food may be dispensed.This allows the researcher to have control over when the animal receives reinforcement, such pallets of food. The earlier boxes contained a lever that when pressed, would cause some food to be dispensed; rats were most commonly used in these boxes. For pigeons, the conditioning chambers were designed with disks to be pecked instead of bars to be pressed on. This study is an example of fixed – interval schedules, as the dispensers were rigged to drop food pellets into the tray at intervals of 15 seconds, regardless of what the pigeon was doing. 4.What were the pigeons conditioned to do as a result? One of the birds was conditioned to turn counter clockwise, making two or three turns between reinforcements. Another bird was repeatedly thrusting its head into one of the upper corners of the cage. Two of the birds developed pendulum motion of the head and body in which the head was extended forward and swung from right to left with a sharp movement followed by a somewhat slower return. One of the other birds was conditioned to make incomplete pecking or brushing movements directed toward but not touching the floor. . How did the pigeons’ behaviour change when the delay period for reinforcement was extended to a minute? With one of the head bobbing and hopping birds, the bird’s movements become more energetic until finally the bobbing and hopping become so intense, that it appeared that the pigeon was doing some kind of dance during the intervals. When the reinforcement in the cage was discounted, the birds’ behaviour was considered extinct. This resulted in the superstitious behaviour disappearing gradually.In the case of the dancing pigeon, there were over 10,000 responses that were recorded before extinction occurred. 5. Was extinction of this behaviour possible? This type of behaviour can persist a lifetime because any behaviour that is reinforced once in a while in a given situation, becomes very difficult to extinguish. This is because the expectation stays high that the superstitious behaviour might w ork to produce reinforcing consequences. In real life, instances of accidental reinforcement usually occur at irregular intervals which make extinction of this behaviour almost impossible. . What explanation does Skinner give for the resiliency to extinction of human superstitions? Skinner states that any behavior that is reinforced once in a while in a given situation, partial reinforcement, it becomes very difficult to extinguish. This is due to the expectation that stays high that the superstitious behaviour might work to produce the reinforcing consequences. In real life, accidental reinforcement usually occurs periodically, so you could imagine why superstitious behaviour may persist for a lifetime. 7.Use Skinner’s operant conditioning principles to explain the development of a superstition that you hold or once held, or one you have observed in someone else. Using Skinner’s operant conditioning principles, I noticed my friend who enjoys roulette had a superstitio n that when he bought himself and the person on his right a drink and place the bet on black he believed he would win. Of course he wouldn’t always win, only the person to his right side won with a free drink, but he always thought this would bring him good luck when he needed it.