ББК Ш143.21-923
Cемашко Л.А. Английский язык: Сборник текстов для студентов факультета психологии. – Челябинск: Изд-во ЮУрГУ, 2006. – 156 с.
Учебное пособие предназначено для домашнего чтения студентов факультета психологии в четвертом семестре и является завершающим этапом профессионально ориентированного обучения. Цель пособия – совершенствование умений полного и внимательного чтения англоязычной литературы по специальности и навыков работы со словарем.
Пособие состоит из семи разделов, каждый из которых включает ряд тематически объединенных текстов. Тексты взяты из оригинальных источников [1–7], имеют познавательную ценность и информативную значимость. Перед каждым текстом дается задание на проверку понимания фактического содержания текста, интерпретацию текста, на определение познавательной ценности прочитанного.
Список лит. – 7 назв.
Одобрено учебно-методической комиссией факультета лингвистики.
Рецензенты: к. пед.н. М.Г. Федотова.
к. пед. н. А. Д. Чурсина.
© Издательство ЮУрГУ, 2006
Contents
PART I. BODY BASICS
Text 1. Brain…………………………………………………………………. 5
Text 2. Brain and Nervous System………………………………………….. 7
Text 3. Human Memory…………………………………………………….. 12
Text 4. Nervous System……………………………………………………… 15
PART II. HEALTH BASICS
Text 5. Genes……………………………………………………………….. 21
Text 6. Health……………………………………………………………….. 23
Text 7. Health and Food…………………………………………………….. 25
Text 8. Regeneration of Nerves……………………………………………… 27
PART III. MENTAL HEALTH
Text 9. Anxiety, Fears and Phobias…………………………………………. 30
Text 10. Brain Injury………………………………………………………… 32
Text 11. Bipolar Disorders…………………………………………………... 36
Text 12. Depressive Disorders………………………………………………. 39
Text 13. Eating Disorders……………………………………………………. 44
Text 14. Fears and Phobias……………………………………………………46
Text 15. Insomnia……………………………………………………………. 49
Text 16. Panic Disorders…………………………………………………….. 52
Text 17. Seasonal Affective Disorder ………………………………………. 53
Text 18. Sleep Disorders……………………………………………………. 57
Text 19. Speech Disorders………………………………………………….. 63
Text 20. Stress ……………………………………………………………… 65
PART IV. DISEASES
Text 21. Alzhmeier`s disease………………………………………………. . 69
Text 22. Autism……………………………………………………………… 71
Text 23. Encephalitis………………………………………………………… 74
Text 24. Hypertension……………………………………………………….. 76
Text 25. Learning Disabilities……………………………………………….. 79
Text 26. Multiple Sclerosis…………………………………………………... 82
Text 27. Pain…………………………………………………………………. 84
Text 28. Schizophrenia………………………………………………………. 88
Text 29. Stroke……………………………………………………………….. 95
PART V. FEELINGS AND EMOTIONS
Text 30. Childhood Stress ……………………………………………… 100
Text 31. Death and Grief………………………………………………… 101
Text 32. How emotions affect health ……………………………………… 106
Text 33. Self-esteem ……………………………………………………… 108
Part VI. Dealing with problems
Text 34. Abusive Relationships……………………………… 111
Text 35. Addiction……………………………………………………… 113
Text 36. Bullying……………………………………………………………. 115
Text 37. Children and Alcohol……………………………………………… 121
Text 38. Children and Smoking…………………………………………… 125
Text 39. Drugs………………………………………………………………. 127
Text 40. Growth Problems in Children…………………………………… 134
Text 41. Obesity ……………………………………………………………. 137
Text 42. Peer pressure ……………………………………………………....140
Text 43. Smoking……………………………………………………………143
Text 44. Teen suicide………………………………………………… 146
PART VII. FAMILY
Text 45. Abuse……………………………………………………………… 149
Text 46. Adoption…………………………………………………………… 152
Text 47. Divorce…………………………………………………………… 153
REFERENCES ……………………………………………………………… 156
Part I. Body basics text 1. Brain
Summarize the text writing one or two sentences for each paragraph.
The human brain is the most complex phenomena in the known universe. When you were in your mother’s womb, each of your 100 000 000 000 brain cells knew how to wire up and what to become. This astonishing process continues into your late teens, sculpting the person you are. However, the truly fundamental factor is not only how this astounding process happens, but why it happens.
Why did the human brain become so complex? Why did we learn to speak? Why do we have certain behaviours? Why did we become so intelligent? And how do our brains differ from a monkey’s or a dolphin’s? All these questions can be answered by the fundamental theory of evolution.
What is evolution? Darwin’s theory of evolution proposes that animals well suited to their environment survive – and pass on their genes. Animals that are not well suited perish before they have offspring. Their mixture of genes die with them.
Over the course of millions of years, this has led to an astounding array of different creatures and organisms on our planet. Each perfectly suited (i.e. adapted) to it’s own environment: ant-eaters with long noses to probe ant-hills, sharks stream-lined to speed through water and bees that work together in a hive.
So how did brains evolve? If you didn’t know about the theory of evolution, how would you explain where brains came from? One option would be they all appeared on the planet one day (the creationist argument). However, armed with an understanding of evolution, you can look at the world in a new way – and work out how animal bodies and behaviours have given them a survival edge over their competitors.
Our brain cells, brain molecules, neurotransmitters and synapses are almost identical in all animals – so the brains of insects, fish, reptiles, birds and mammals are all made from the same building blocks.
Again evolution can explain the amount of brain devoted to a particular task. Crocodiles have huge olfactory bulbs, the area of the brain that deals with smell. In contract, humans have vast areas of the brain devoted to vision. Evolution can even explain how the vast array of animal behaviours came into being.
Early brains. Early brains on our planet were very simple – and are found now in animals lower down the evolutionary ‘tree’ for example in insects, worms and snails. These early brains are more collections of ganglia – where hundreds of nerve cell bodies congregate. Fish and amphibians have well defined brains – albeit small ones in relation to their body size. Reptiles and bird brains become ever more complex with areas devoted to specific senses, for example vision and smell. Mammals have a vast variety of brain shapes and sizes. The biggest brain on our planet belongs to the blue whale – weighing in at 6kg, compared to the 1.4 kg brain of a human.
Does size matter? Interestingly, size isn’t everything – and provides us with a bit of a puzzle. The North American hummingbird has a brain weighing less than a gram, whereas a blue whale has a 6 kg brain. Yet both show a marvelous variety of behaviours. Both sing, defend territories, attract mates, raise young and migrate seasonally for long distances. The tiny-brained hummingbird also has an elaborate courtship dance, builds nests and solves some interesting pattern-recognition problems in finding flowers.
Do intelligent mammals have bigger brains? In general yes, but only when considered as a proportion of their overall body size.
A good indication of intelligence is brain weight in relation to body weight.
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It seems that carnivores have bigger brains in relation to their body size than their prey – presumably giving them the advantage to create tactics and strategies to catch prey.
Animals that eat seeds and fruits (frugivores) have larger brains than similar sized animals that eat foliage and leaves (folivores) presumably allowing them to distinguish the colours and shapes of ripe fruits to satisfy their discerning tastes.
Careful parents outrank the careless in terms of relative brain size. And animals with proportionally bigger brains show a wider range of complex behaviours.
When did humans evolve such huge brains? Hominid brains have evolved and grown from 400g 3-4 million years, to their present size of 1400g (1.4kg). The bodies of Homo erectus (1.7 million years ago) were not substantially smaller than humans of the last century, yet their brains were nearly half the size.
There are lots of questions about brain evolution that scientists are still working on – but there is overwhelming evidence that brain complexity and ‘intelligence’ are hugely beneficial in an evolutionary sense.
Brain evolution and babies brains. More intelligent mammals such as dolphins, chimps and humans have highly convoluted brains compared to the smooth brains of less intelligent animals. However, intelligence is also related to how big an animal’s brain is relative to its body size. Interestingly, as we developed in our mother’s womb our brains also had a smooth surface until 6 months, developing convolutions before birth.
This picture shows three model brains.
The smallest is a premature baby’s brain (at 26 weeks), the middle is a newborn baby’s brain and the largest is an adult’s fully-grown brain. Premature babies are born with a smooth brain, and the convolutions develop in the few months after birth.
Why has consciousness evolved? This question continues to puzzle scientists. Why is it that humans have an awareness of their own existence, and why does this give an evolutionary advantage? Perhaps consciousness is needed to make sense of what you see.
An understanding of evolution is fundamental to understanding brain science – and indeed all biological sciences. Over the past several hundred years, there have been two, perhaps three fundamental upheavals in human thought.
Firstly, The Copernican Revolution – that far from being the centre of the universe, the earth is simply one of several planets orbiting our sun.
Secondly, The Darwinian Revolution – that by the astounding process of evolution, every living thing on the planet has evolved into the huge variety of colours, shapes, sizes and behaviours we see today.
One could argue that understanding DNA was the third revolution, and in the future understanding the human brain and consciousness might be the forth.
TEXT 2. BRAIN AND NERVOUS SYSTEM
Read the text and state the problems that affect the brain.
The brain does not only control what you think and feel, how you learn and remember, and how you move and talk, but also many things you’re less aware of – such as the beating of your heart, the digestion of your food, and even the amount of stress you feel.
Anatomy of the nervous system. If you think of the brain as a central computer that controls all the functions of your body, then the nervous system is like a network that relays messages back and forth from it to different parts of the body. It does this via the spinal cord, which runs from the brain down through the back and contains threadlike nerves that branch out to every organ and body part.
When a message comes into the brain from anywhere in the body, the brain tells the body how to react. For example, if you accidentally touch a hot stove, the nerves in your skin shoot a message of pain to your brain. The brain then sends a message back telling the muscles in your hand to pull away. Luckily, this neurological relay race takes a lot less time than it just took to read about it!
Considering everything it does, the human brain is incredibly compact, weighing just 3 pounds. Its many folds and grooves, though, provide it with the additional surface area necessary for storing all of the body’s important information.
The spinal cord, on the other hand, is a long bundle of nerve tissue about 18 inches long and 3/4 inch thick. It extends from the lower part of the brain down through spine. Along the way, various nerves branch out to the entire body. These are called the peripheral nervous system.
Both the brain and the spinal cord are protected by bone: the brain by the bones of the skull, and the spinal cord by a set of ring-shaped bones called vertebrae. They’re both cushioned by layers of membranes called meninges as well as a special fluid called cerebrospinal fluid. This fluid helps protect the nerve tissue, keep it healthy, and remove waste products.
The brain is made up of three main sections: the forebrain, the midbrain, and the hindbrain.
The forebrain. The forebrain is the largest and most complex part of the brain. It consists of the cerebrum – the area with all the folds and grooves typically seen in pictures of the brain – as well as some other structures beneath it.
The cerebrum contains the information that essentially makes us who we are: our intelligence, memory, personality, emotion, speech, and ability to feel and move. Specific areas of the cerebrum are in charge of processing these different types of information. These are called lobes, and there are four of them: the frontal, parietal, temporal, and occipital.
The cerebrum has right and left halves, called hemispheres, which are connected in the middle by a band of nerve fibers (the corpus collosum) that enables the two sides to communicate. Though these halves may look like mirror images of each other, many scientists believe they have different functions. The left side is considered the logical, analytical, objective side. The right side is thought to be more intuitive, creative, and subjective. So when you’re balancing the checkbook, you’re using the left side; when you’re listening to music, you’re using the right side. It’s believed that some people are more "right-brained" or "left-brained" while others are more "whole-brained," meaning they use both halves of their brain to the same degree.
The outer layer of the cerebrum is called the cortex (also known as "grey matter"). Information collected by the five senses comes into the brain from the spinal cord to the cortex. This information is then directed to other parts of the nervous system for further processing. For example, when you touch the hot stove, not only does a message go out to move your hand but one also goes to another part of the brain to help you remember not to do that again.
In the inner part of the forebrain sits the thalamus, hypothalamus, and pituitary gland. The thalamus carries messages from the sensory organs like the eyes, ears, nose, and fingers to the cortex. The hypothalamus controls the pulse, thirst, appetite, sleep patterns, and other processes in our bodies that happen automatically. It also controls the pituitary gland, which makes the hormones that control our growth, metabolism, digestion, sexual maturity, and response to stress.
The midbrain. The midbrain, located underneath the middle of the forebrain, acts as a master coordinator for all the messages going in and out of the brain to the spinal cord.
The hindbrain. The hindbrain sits underneath the back end of the cerebrum, and it consists of the cerebellum, pons, and medulla. The cerebellum – also called the "little brain" because it looks like a small version of the cerebrum – is responsible for balance, movement, and coordination.
The pons and the medulla, along with the midbrain, are often called the brainstem. The brainstem takes in, sends out, and coordinates all of the brain’s messages. It is also controls many of the body’s automatic functions, like breathing, heart rate, blood pressure, swallowing, digestion, and blinking.
How the nervous system works. The basic functioning of the nervous system depends a lot on tiny cells called neurons. The brain has billions of them, and they have many specialized jobs. For example, sensory neurons take information from the eyes, ears, nose, tongue, and skin to the brain. Motor neurons carry messages away from the brain and back to the rest of the body. All neurons, however, relay information to each other through a complex electrochemical process, making connections that affect the way we think, learn, move, and behave.
Intelligence, learning, and memory. At birth, your nervous system contains all the neurons you will ever have, but many of them are not connected to each other. As you grow and learn, messages travel from one neuron to another over and over, creating connections, or pathways, in the brain. It’s why driving seemed to take so much concentration when you first learned but now is second nature: The pathway became established.
In young children, the brain is highly adaptable; in fact, when one part of a young child’s brain is injured, another part can often learn to take over some of the lost function. But as we age, the brain has to work harder to make new neural pathways, making it more difficult to master new tasks or change established behavior patterns. That’s why many scientists believe it’s important to keep challenging your brain to learn new things and make new connections – it helps keeps the brain active over the course of a lifetime. Memory is another complex function of the brain. The things we’ve done, learned, and seen are first processed in the cortex, and then, if we sense that this information is important enough to remember permanently, it’s passed inward to other regions of the brain (such as the hippocampus and amygdala) for long-term storage and retrieval. As these messages travel through the brain, they too create pathways that serve as the basis of our memory.
Movement. Different parts of the cerebrum are responsible for moving different body parts. The left side of the brain controls the movements of the right side of the body, and the right side of the brain controls the movements of the left side of the body. When you press the accelerator with your right foot, for example, it’s the left side of your brain that sends the message allowing you to do it.
Basic body functions. A part of the peripheral nervous system called the autonomic nervous system is responsible for controlling many of the body processes we almost never need to think about, like breathing, digestion, sweating, and shivering. The autonomic nervous system has two parts: the sympathetic and the parasympathetic nervous systems.
The sympathetic nervous system prepares the body for sudden stress, like if you see a robbery taking place. When something frightening happens, the sympathetic nervous system makes the heart beat faster so that it sends blood more quickly to the different body parts that might need it. It also causes the adrenal glands at the top of the kidneys to release adrenaline, a hormone that helps give extra power to the muscles for a quick getaway. This process is known as the body’s "fight or flight" response.
The parasympathetic nervous system does the exact opposite: It prepares the body for rest. It also helps the digestive tract move along so our bodies can efficiently take in nutrients from the food we eat.
The senses:
Sight. Sight probably tells us more about the world than any other sense. Light entering the eye forms an upside-down image on the retina. The retina transforms the light into nerve signals for the brain. The brain then turns the image right-side up and tells us what we are seeing.
Hearing. Every sound we hear is the result of sound waves entering our ears and causing our eardrums to vibrate. These vibrations are then transferred along the tiny bones of the middle ear and converted into nerve signals. The cortex then processes these signals, telling us what we are hearing.
Taste. The tongue contains small groups of sensory cells called taste buds that react to chemicals in foods. Taste buds react to sweet, sour, salty, and bitter. Messages are sent from the taste buds to the areas in the cortex responsible for processing taste.
Smell. Olfactory cells in the mucous membranes lining each nostril react to chemicals we breathe in and send messages along specific nerves to the brain – which, according to experts, can distinguish between more than 10,000 different smells. With that kind of sensitivity it’s no wonder that smells are very closely linked to our memories.
Touch. The skin contains more than 4 million sensory receptors – mostly concentrated in the fingers, tongue, and lips – that gather information related to touch, pressure, temperature and pain and send it to the brain for processing and reaction.
Things that can go wrong with the brain. Because the brain controls everything, when something goes wrong with it, it’s often serious and can affect many different parts of the body. Inherited diseases, brain disorders associated with mental illness, and head injuries can all affect the way the brain works and upset the daily activities of the rest of the body.
Problems that can affect the brain include:
Brain tumors. A tumor is a swelling caused by overgrown tissue. A tumor in the brain may grow slowly and produce few symptoms until it becomes large, or it can grow and spread rapidly, causing severe and quickly worsening symptoms. Brain tumors in children can be benign or malignant. Benign tumors usually grow in one place and may be curable through surgery if they’re located in a place where they can be removed without damaging the normal tissue near the tumor. A malignant tumor is cancerous and more likely to grow rapidly and spread.
Cerebral palsy. Cerebral palsy is the result of a developmental defect or damage to the brain before or during birth. It affects the motor areas of the brain. A person with cerebral palsy may have average intelligence or can have severe developmental delays or mental retardation. Cerebral palsy can affect body movement in many different ways. In mild cases of cerebral palsy, there may be minor muscle weakness of the arms and legs. In other cases, there may be more severe motor impairment – a child may have trouble talking and performing basic movements like walking.
Epilepsy. This condition is made up of a wide variety of seizure disorders. Partial seizures involve specific areas of the brain, and symptoms vary depending on the location of the seizure activity. Other seizures, called generalized seizures, involve a larger portion of the brain and usually cause uncontrolled movements of the entire body and loss of consciousness when they occur. Although the specific cause is unknown in many cases, epilepsy can be related to brain injury, tumors, or infections. The tendency to develop epilepsy may be inherited in families.
Headaches. Of the many different types of headaches, the most frequently occurring include tension headache (the most common type), caused by muscle tension in the head, neck, and shoulders; migraine, an intense, recurring headache with an unclear cause; and cluster headache, considered by some to be a form of migraine. Migraines occur with or without warning and may last for several hours or days. There seems to be an inherited predisposition to migraines as well as certain triggers that can lead to them. People with migraines may experience dizziness, numbness, sensitivity to light, and nausea, and may see flashing zigzag lines before their eyes.
Meningitis and encephalitis. These are infections of the brain and spinal cord that are usually caused by bacteria or viruses. Meningitis is an inflammation of the coverings of the brain and spinal cord, and encephalitis is an inflammation of the brain tissue. Both conditions may result in permanent injury to the brain.
Mental illness. Mental illnesses are psychological and behavioral in nature and involve a wide range of problems in thought and function. Certain mental illnesses are now known to be linked to structural abnormalities or chemical dysfunction of the brain. Some mental illnesses are inherited, but often the cause is unknown. Injuries to the brain and chronic drug or alcohol abuse also can trigger some mental illnesses. Signs of chronic mental illnesses such as bipolar disorder or schizophrenia may first show up in childhood. Mental illnesses that can be seen in younger people include depression, eating disorders such as bulimia or anorexia nervosa, obsessive-compulsive disorder (OCD), and phobias.
Head injuries. Head injuries fit into two categories: external (usually scalp) injuries and internal head injuries. Internal injuries may involve the skull, the blood vessels within the skull, or the brain. Fortunately, most childhood falls or blows to the head result in injury to the scalp only, which is usually more frightening than threatening. An internal head injury could have more serious implications because the skull serves as the protective helmet for the delicate brain.
Concussions are also a type of internal head injury. A concussion is the temporary loss of normal brain function as a result of an injury. Repeated concussions can result in permanent injury to the brain. One of the most common reasons kids get concussions is through sports, so it’s important to make sure they wear appropriate protective gear and don’t continue to play if they’ve had a head injury.
TEXT 3. HUMAN MEMORY
Read the text and describe human memory using the diagram below.
Human Memory. There are generally three types of memory: sensory memory, short-term memory and long-term memory.
Sensory memory. The sensory memories act as buffers for stimuli received through the senses. A sensory memory exists for each sensory channel: iconic memory for visual stimuli, echoic memory for aural stimuli and haptic memory for touch. Information is passed from sensory memory into short-term memory by attention, thereby filtering the stimuli to only those which are of interest at a given time.
Short-term memory. Short-term memory acts as a scratch-pad for temporary recall of the information under process. For instance, in order to understand this sentence you need to hold in your mind the beginning of the sentence you read the rest.
Short term memory decays rapidly (200 ms.) and also has a limited capacity. Chunking of information can lead to an increase in the short term memory capacity. Thst is the reason why a hyphenated phone number is easier to rememeber than a single long number. The successful formation of a chunk is known as closure. Interference often causes disturbance in short-term memory retention. This accounts for the desire to complete the tasks held in short term memory as soon as possible.
Long-term memory. Long-term memory is intended for storage of information over a long time. Information from the working memory is transferred to it after a few seconds. Unlike in working memory, there is little decay.
There are two types of long-term memory: episodic memory and semantic memory. Episodic memory represents our memory of events and experiences in a serial form. It is from this memory that we can reconstruct the actual events that took place at a given point in our lives. Semantic memory, on the other end, is a structured record of facts, concepts and skills that we have acquired. The information in semantic memory is derived from that in our own episodic memory, such that we can learn new facts or concepts from our experiences.
Long-term memory processes. There are three main activities related to long term memory: storage, deletion and retrieval.
Information from short-term memory is stored in long-term memory by rehearsal. The repeated exposure to a stimulus or the rehearsal of a piece of information transfers it into long-term memory. Experiments also suggest that learning time is most effective if it is distributed over time. Deletion is mainly caused by decay and inerference. Emotional factors also affect long-term memory. However, it is debatable whether we actually ever forget anything or whether it becomes increasingly difficult to access certain items from memory. Having forgotten something may just be caused by not being able to retrieve it! Information may not be recalled sometimes but may be recognized, or may be recalled only with prompting. This leads us to the third process of memory: information retrieval.
There are two types of information retrieval: recall and recognition. In recall, the information is reproduced from memory. In recognition the presentation of the information provides the knowledge that the information has been seen before. Recognition is of lesser complexity, as the information is provided as a cue. However, the recall can be assisted by the provision of retrieval cues which enable the subject to quickly access the information in memory.
Thought processes. Cogito ergo sum (I think therefore I am). These words of Descartes sum up the importance of thought processes in humans and probably the most important reason we differ from animals. Although animals retrieve and store information, there is little evidence to suggest that they can use it in quite the same way as humans. Humans, on the other hand, are able to use information to reason and solve problems, even when the information is partial or unavailable.
Thinking can be categorized into reasoning and problem solving. Although these are not distinct they are helpful in clarifying the processes involved.
Reasoning. Reasoning is the process by which we use the knowledge we have to draw conclusions or infer something we know about the domain of interest. Reasoning is classified as being deductive, inductive or abductive. Deductive reasoning involves deciding what must be true given the rules of logic and some starting set of facts (premises). Inductive reasoning involves deciding what is likely to be true given some starting set of beliefs or observations.
Deductive reasoning. Deductive reasoning derives the logically necessary conclusion from the given premises. It is important to note that it can lead to a logical conclusion which conflicts with our knowledge of the world. For example, if it is raining then the ground is dry. It is raining. Therefore the ground is dry. It is a perfectly valid deduction! Deductive reasoning is therefore often misapplied. Human deduction is at its poorest when truth and validity clash. This is because people bring their knowledge of the real world into the reasoning process as it allows them to take short cuts which make information processing more efficient.
Inductive reasoning. Induction is generalizing from cases we have seen to infer information about cases we haven’t. For instance, if all the dogs that we have seen are white, we may infer that all dogs are white in colour. This is disproved when we see a black dog! In the absence of counter examples, all that we can do is gather evidence to support our inductive inference. In spite of its unreliability, induction is a useful process which we use constantly in learning about our environment.
Abductive reasoning. Abduction reasons from a fact to the action that caused it. This is the method we use to derive explanations for the events we observe. This kind of reasoning, although useful, can lead to unreliability as an action preceding an event can be wrongly attributed as the cause of the event.
Problem solving. Problem solving is the process of finding a solution to an unfamiliar task, using the knowledge we have. There are a number of different views of how people solve problems. We shall consider two of the more recent and influential views: Gestalt theory and the problem space theory.
Gestalt theory. Gestalt theory claims that problem solving is productive and reproductive. Reproductive problem solving draws on previous experiences whereas productive problem solving involves insight and restructuring of the problem. Reproductive problem solving could be a hindrance to finding a solution, since a person may fixate on the known aspects of a problem and so be unable to see novel interpretations that might lead to a solution. A well known example of this is Maier’s `pendulum problem’. The problem was to tie together pieces of string hanging from the ceiling. However, they were far too apart to catch hold of both at once. The room was full of other objects including pliers, poles and extensions. Although various solutions were proposed by participants, few chose to use the weight of the pliers as a pendulum to swing the strings together. However, when the experimenter brushed against the string, setting it in motion, a lot of participants came up with the idea. This can be interpreted as an example of productive restructuring. This experiment also illustrates fixation: participants were unable to see any method beyond the use of a pair of pliers.
Problem space theory. The problem space theory was proposed by Newell and Simon. The theory says that problem solving centers around the problem space. This space comprises of problem states which can be generated using legal transition operators.
For example, imagine you are reorganizing your office and you want to move the desk from one end to another. The two different states are represented by the locations of the desk. A number of operators can be applied to move these things: they can be carried, pushed, dragged etc. In order to ease the transition between the states, you have a new sub-goal: to make the desk light. These may involve operators such as removing drawers and so on.
Within the problem space framework, experience allows us to solve problems more easily since we can structure the problem space appropriately and choose operators efficiently.
Analogy in problem solving. People solve novel problems by mapping knowledge in a similar known domain to it. For instance, to destroy malignant tumour it is essential to fire low intensity rays from all sides, as high intensity rays can damage healthy tissues. An analogous case is that of attacking a fortress. However, people miss analogous information unless it is semantically close to the problem domain.
Skill acquisition. Skills in a given problem area differentiate the novice from the expert. A commonly studied domain is chess playing. It is particularly suitable since it lends itself to representation in terms of problem space theory, in which the initial board configuration and the final position constitute the states while the moves appeared as transition operators. Masters took lesser time than novices to react to a situation and produced better moves. This is largely because chess masters remember board configurations and good moves associated with them. They can chunk the board configuration in order to hold it in short-term memory.
Skilled behavior becomes automatic over a period of time. Experts tend to mentally rehearse their actions in order to identify exactly what they do. Although such skilled behavior is efficient it may cause errors when the context of the activity changes.
Individual differences. The psychological principles and properties that have been discussed apply to the majority of people. However, there are individual differences which affect a small percentage. The differences may be long term such as sex, physical capabilities and individual capabilities. Others are for a shorter duration and may include the effects of stress or failure on the user. Still others may change through time such as age. These differences should be taken into account in interface designs to eure that a grensater population of users is benefited.