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Under and Around the Red Sea

Tomb of the Pyramid Builders

Science and the Brain

Oasis of the Ancestors

Saving Storks in the Sinai

Ancient Flutes in Egypt
in the classroom

SHOW 304: Science and the Brain

Can a mother recognize her new infant by sight? Maybe not. Experiments performed at the Shaare Zedek Medical Center in Jerusalem demonstrate how much more powerful are the more primitive senses of smell and touch in the short but critical time after birth. In a separate study at Israel's Wingate Institute, athletes learn how biofeedback combined with hi-tech monitoring can perfect their skills.

Activity 1: Test Your Sense of Smell
Activity 2: Biofeedback Techniques



On FRONTIERS, neonatologist Arthur Eidelman and psychologist Marsha Kaitz demonstrate a phenomenon casually referred to as the "mush-brain effect." After giving birth, the higher-level cognitive functions of new mothers appear to diminish, and more primitive senses of smell and touch become sharper.

Have you ever experienced the "mush-brain effect"? According to Dr. Eidelman, the combined effects of stress, fatigue and hormonal changes "turn the brain to mush," that is, disturb the cognitive-cortical functioning. The effects are particularly severe in mothers who have recently given birth. "Stress and fatigue can affect the ability to absorb new information and even cause short-term memory lapses," says Eidelman. How might this study apply to people besides new mothers? For example, should you take the SATs after a strenuous physical workout?

Eidelman and Kaitz's studies support the argument for new mothers (and fathers) having direct, immediate, skin-to-skin contact with their infants, so as to encourage the recognition and attachment process.



Many biologists believe that our early ancestors' sense of smell was more highly developed than is ours today. Why do you think that might be?

Try this experiment with a partner or small group of people to find out how keen your sense of smell is. Select samples of items from the list below; place a small amount of each in a baby food jar or other glass container that can be covered. The subject should not see any of the containers and should be blindfolded for the test. Open one container at a time and invite the subject to smell it; ask the subject to identify the item and record the answers in a notebook. How many items can each subject identify? Next, have the subject try to identify the items in the jars and remember the order in which they were presented. For subsequent subjects, mix up the order.

  • coffee grounds
  • perfume
  • herb tea
  • soap
  • garlic
  • flowers
  • ammonia
  • banana
  • popcorn
  • vinegar

  • People can detect over 10,000 different odors.

  • Heredity determines the keenness of a person's sense of smell.

  • Perfume probably originated with the Egyptians, the first people to use it regularly and lavishly. Perfumes were used as magical hexes and as medicine, as well as to scent the skin. At formal banquets, Egyptian women often wore perfumed wax cones that melted and dripped down over their head and shoulders during the evening. Men also wore perfume.

  • A Natural History of the Senses by Diane Ackerman (Random House, 1990) and All the Rage (Time-Life Books, 1992).

  • As you see on FRONTIERS, the technique of biofeedback can help athletes improve concentration and control. Through biofeedback, people gather information about physiological phenomena such as heart rate, blood pressure, brain waves and body temperature; special equipment feeds the information back to the person, who learns how to control the reaction.

  • Biofeedback techniques can help people overcome many illnesses, including headaches, muscle spasms, anxiety, erratic heartbeats and others. When biofeedback was first introduced, the medical community scoffed; but this and other alternative forms of healing are becoming more accepted today.

  • Visualization and imaging are two other methods of using the mind to affect the body in positive ways. In a simplistic form of guided imaging, try to warm your cold hands and feet by imagining yourself lying on a beach near the Red Sea or climbing a pyramid in Egypt. The techniques are believed by many to be especially helpful in reducing stress and promoting relaxation.

  • Have you ever tried similar techniques, either to relax or improve your concentration?

  • Are there aspects of your athletic performance (or other activities) you'd like to improve?

  • Do you think such techniques can help?

  • Look for more ways researchers are studying these and other techniques.

  • How "scientific" are the conclusions?


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.