A. A condition that causes children to dislike being hugged and sometimes reject all phys- ical affection is closer to being understood following research into the part of the brain responsible for our senses. Scientists at Northwestern University, Illinois, and the Univer- sity of Edinburgh explored fragile X syndrome, a condition associated with hypersensitivity to sounds, touch, smells and visual stimuli that can result in social withdrawal or anxiety. Hypersensitivity is a condition in which the person affected responds in an excessive way to contact with the world around them. Some sufferers are even hypersensitive to material on their skin. B. The scientists found that critical phases in the brain's development may be delayed in people with the condition. This may result in slower communication between certain neu- rons in the brain. By recording electrical signals in the brains of mice, bred to exactly copy the effects of the condition, the researchers found that connections in the brain's sensory cortex were late to develop fully. The study, published in the journal Neuron, found that normal neural connections in the sensory cortex occur much earlier than previously thought: in the first week of pregnancy in mice, which is equivalent to the middle of the second trimester (or fifth month) of pregnancy in humans. In fragile X syndrome, the mis- timing also has a domino effect causing further problems with the correct wiring of the brain. The hope is that by understanding how and when the functions of the brain are af- fected in fragile X syndrome, a therapy may become possible. C. "There is a 'critical period' during development, when the brain is very plastic and is changing rapidly," said Anis Contractor, from the Feinberg School of Medicine at North- western University. "All the elements of this rapid development have to be coordinated so that the brain becomes wired correctly and therefore functions properly." When this does not happen, a number of symptoms appear. People with the syndrome have cognitive prob- lems as well as sensory problems that make them physically weaker. "They have tactile defensiveness," Dr Contractor said. "They don't look in people's eyes, they won't hug their parents, and they are hypersensitive to touch and sound. All of this causes anxiety for family and friends as well as for the fragile X patients themselves." Peter Kind, who led the study at the University of Edinburgh, said: "We know there are key windows during which the brain develops, both in the womb and afterwards. The general principle is that if these time windows have shifted, then that could explain the cognitive problems." D. Professor Kind said that this could be demonstrated by the fact that a child with a cataract (a medical condition in which the lens of the eye becomes less and less transparent) that was not corrected would become permanently blind in the affected eye, whereas an adult would be able to regain their sight after an operation. "We've learnt that these changes happen much earlier than previously thought, which gives valuable insight into when we should begin therapeutic intervention for people with these conditions," he said. "It also has implications for the treatment of autism since the changes in the brains of people with fragile X syndrome and autistic people are thought to significantly overlap." Autism, as many people know, is a disability that affects how a person communicates with and relates to other people, and how they make sense of the world. E. Fragile X syndrome is as common as cystic fibrosis, a genetic disorder that commonly affects the lungs and causes breathing difficulties, and that affects about 1 in 4,000 males and 1 in 8,000 females worldwide. The Fragile X Society believes that there are many people who have the fragile X syndrome but have never been diagnosed. It shows up in early infancy and progressively worsens throughout childhood, causing intellectual disa- bility as well as social, language and behavioural problems. F. Fragile X syndrome is caused by a gene mutation on the X chromosome one of the two chromosomes that determine the gender or sex of a person. The mutation interferes in the production of a protein called fragile X mental retardation protein. Fragile X is so- named because the X chromosome appears broken or kinked. Tim Potter, of the Fragile X Society, said: "We welcome any research that helps us understand fragile X and which may open the way to reversing the effects or preventing them ever happening." Passage 3 has six paragraphs A-F. For Questions 28 to 33, choose the correct heading for paragraphs A-F from the list of headings below. Write the correct numbers, i-ix in the boxes on your Answer Sheet. Questions 28 to 33 List of Headings i. Fragile X syndrome and developmental delays in the brain ii. A definition of fragile X syndrome iii. Reasons for the increase of fragile X syndrome iv. New treatments for fragile X syndrome V. Fragile X syndrome happens more often than we think vi. The genetic basis of fragile X syndrome vii. Examples of the symptoms of fragile X syndrome viii. How fragile X syndrome was discovered ix. Other conditions related to cognitive development 28. Paragraph A 29. Paragraph B 30. Paragraph C 31. Paragraph D 32. Paragraph E 33. Paragraph F For Questions 34 to 39, complete the summary below using the words in the box below. Use NO MORE THAN TWO WORDS from the FIRST TWO paragraphs (A and B) of the passage for each answer. Write your answers clearly on your Answer Sheet. Questions 34 to 39 People with fragile X syndrome are extremely sensitive to sensory 34. Some sufferers are even 35._ nections within the 36. stead, the 37. hypersensitive sensory cortex should happen, which is normally in the second 38. mans. By understanding how the brain's 39. develop a treatment. A. B. C. D. of the brain not being made at the right time. In- of people with the condition establish connections later than neurons stimuli to clothing. The condition is the result of con- dislike functions month anxiety Section 3 Part 3- Multiple Choice Question (2 marks) Question 40 Complete the title of Reading Passage 3. Study reveals common bond of children who are autistic. hate to be hugged. have complete X chromosomes. have highly plastic brains. of pregnancy in hu- are affected, scientists hope to fragile trimester For Question 40, choose the correct letter, A, B, C or D. Write your answer clearly on your Answer Sheet.