1. Remind the class that the previous lesson focused on human communication. If you have saved the Path to Understanding diagram from Lesson 1, review it with the class. Explain to students that they will now explore how humans understand what they hear.
2. Illustrate the multisensory nature of communication by silently mouthing a sentence such as, “I wonder if you can read my lips.” Ask the class if they can repeat the sentence that you mouthed.

Students may be able to pick out some of the words, but the meaning of the sentence will remain obscure. If you have a hearing-impaired student in the class who is adept at reading lips, ask him or her to let the rest of the class respond first.

3. Next, silently mouth a sentence such as, “You’re the best class that I’ve ever had,” while conveying a happy facial expression. As before, the exact meaning of the sentence will be obscure. Ask the class if they think the sentence was conveying a happy, sad, or angry thought. On what did the students base their impression?

You should stress that facial expressions help represent the emotion behind speech.

4. Finally, silently mouth a sentence such as, “I’ve just won $1 million in the lottery.” This time use a facial expression that conveys an angry or sad emotional state and ask the class to identify the emotion behind the sentence. Again, ask students to explain the basis for their answers.

The mixed messages sent by the mouthed words and the facial expression make the meaning of the sentence more difficult to establish.

5. Ask the class to summarize how visual cues influence communication and understanding.

Students should realize that visual cues, such as facial expressions, affect how others interpret what is said.

Figure 2.3. The meaning of spoken words can change depending on how the words are spoken.

1. Ask the class, Can you detect the emotional state of the person speaking by his or her tone alone, or do you need to understand the words being spoken?

Answers will vary, though many students will believe that they can identify the speaker’s emotional state just by hearing the tone and not the words.

2. Test this idea by speaking a random string of numbers to the class, such as 7, 52, 12, 39, 75. Use a voice that suggests a specific emotion, such as anger, and ask the students to identify the emotion.

To avoid giving the class any visual cues from your facial expression, you might face away from the class while speaking.

3. Ask for a volunteer to repeat the test by speaking a different string of numbers and using a different emotion. See if the class can identify the emotion. Repeat the test using different students, numbers, and emotions.

Again, have the speaker face away from the class to eliminate cues from facial expressions.

Content Standard C:
Behavior is one kind of response an organism can make to an internal or environmental stimulus.

4. To reinforce the importance of multisensory communication, ask the class what other factors, besides hearing, help us communicate with others.

Answers should include the idea that visual cues, such as facial expressions and body language, help our brain interpret the speech that we hear.

5. Wrap up the activity by asking students to list ways, other than speech, in which we can communicate.

Answers will vary but may include

1. Remind the class that we categorize sounds as voiced, musical, or environmental. Ask students to give some examples of each category.
2. Explain to the class that they will take a short walk. Instruct students not to talk to each other during the walk and to keep noise to a minimum.

The goal is to concentrate on the number and types of sounds around them and list as many of them as possible. For the purposes of this activity, students should ignore any sounds made by students in the class (such as talking, coughing, feet shuffling, and writing) and only pay attention to those sounds that aren’t produced by the class.

Content Standard A:
Different kinds of questions suggest different kinds of scientific investigations. Some investigations involve observing and describing objects, organisms, or events; some involve collecting specimens; some involve experiments; some involve seeking more information; some involve discovery of new objects and phenomena; and some involve making models.


Assessment:
Ask students to summarize, in writing, their thoughts about how audio and visual cues influence our ability to gain meaning from sound. Ask them to provide specific examples of sounds that can have different meanings depending upon their context. Ask students to share their ideas with the class.

3. Give each student a copy of Master 2.1, Sound Safari Data Sheet. Explain that each of the sounds they list can be classified as voiced, musical, or environmental. Instruct students to list each of their sounds in the appropriate column on their data sheet.

Environmental sounds are simply those that are not voiced or musical.

4. After returning to the classroom, place an overhead transparency of Master 2.1, Sound Safari Data Sheet, on the overhead projector. Ask students to call out the voiced sounds from their data sheets and write them down on the transparency. Repeat this process for the musical and environmental sounds.
5. Ask students whether their list of sounds was the same as that written on the transparency. Ask the class to account for differences.

Students will have many of the same sounds on their lists. Differences arise when sounds are hard to hear or are ever present and therefore difficult to notice.

6. To conclude this activity, remind the class that visual and audio cues help us better understand speech. Ask the class if they can think of similar cues that help us understand musical and environmental sounds.

Context is important. A piece of music played during a parade may convey a different emotion from the same music played at a funeral. A whistle blown by a policeman directing traffic has a different meaning from a whistle blown by an official at a sporting event.