81. Hundreds of thousands of cardiac arrests that occur every year, according to the Canadian scientists, could be attributed to ____.

1. constant blood pressure
2. a mysterious region in the brain
3. unexplained cardiovascular clots
4. the abnormalities in the brain's cardiovascular control center

82. The experiment on five subjects was intended ____.

1. to localize the insular cortex
2. to spot the activated areas in their brains
3. to explore the functions of the insular cortex
4. to determine the relationship between stress and blood pressure

83. Both King's and Cechetto's research boiled down to ____.

1. the traditional factors like poor diet and clogged arteries
2. the same activated region in the rats' brains
3. the brain's cardiovascular control center
4. the insular cortex in the human brain

84. The team would like to extend their findings to the relationship between ____.

1. heart disease and sudden death
2. the neural basis and life styles
3. the brain and internal organs
4. stress and heart disease

85. The researchers hope to find out if

1. there exists a link between the neural areas and stress-related heart attacks
2. the insular cortex can bring about stress and anger
3. many heart attacks are preventable
4. all of the above

(Reference keys.)