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  • 标题:Effects of message sensation value in bird flu TV stories on audience arousal and perception of story quality.
  • 作者:Wei, Ran ; Zhou, Shuhua
  • 期刊名称:China Media Research
  • 印刷版ISSN:1556-889X
  • 出版年度:2010
  • 期号:April
  • 语种:English
  • 出版社:Edmondson Intercultural Enterprises
  • 摘要:The activation theory of information exposure was applied mostly in researching substance abuse among youth. The focus was on testing what kind of media campaign messages, such as public service announcements (PSAs), are most effective in persuading high-sensation seekers from using drugs. In this study, the activation theory of information exposure was applied in a different context--health communication about the threat of a bird flu pandemic in the United States.
  • 关键词:Interest (Psychology);Message framing;Sensationalism

Effects of message sensation value in bird flu TV stories on audience arousal and perception of story quality.


Wei, Ran ; Zhou, Shuhua


Although human beings are characterized as voracious information seekers, not all of us are "informavores" (Dennett, 1991). Research shows that individuals use mass media and attend to media messages for a variety of reasons and to fulfill very different needs (Blumler & Katz, 1974). With an explicit focus on message exposure as need-fulfillment, the activation theory of information exposure (Donohew, Lorch, & Duncan, 1980; Donohew, Lorch, & Palmgreen, 1998) underscores the importance of the need for stimulation in motivating individuals to attend to media messages. The thesis is that motivation to message exposure is driven by the need for stimulation rather than cognitive need for information alone (Donohew, 1990). Specifically, the theory proposes that sensation-seekers tend to view media stimuli to satisfy their desire for stimulation or arousal (Frankenberger, 2004; Stephenson, 2002). The generalization is that high arousal messages gain attention and is preferred by high-sensation seekers when attending to a message (Stephenson & Southwell, 2006).

The activation theory of information exposure was applied mostly in researching substance abuse among youth. The focus was on testing what kind of media campaign messages, such as public service announcements (PSAs), are most effective in persuading high-sensation seekers from using drugs. In this study, the activation theory of information exposure was applied in a different context--health communication about the threat of a bird flu pandemic in the United States.

The threat of a bird-infected flu known as H5N1 (avian flu) pandemic has garnered attention from the news media in the past few years. Since 2003, a total of 407 people in 15 Asian African and European countries were infected; more than half of them (254) died. Over 200 million birds died or were destroyed. Just a couple of months into 2009, four deaths were reported in China. Fearing the virus may mutate and cause human-to-human infections, the World Health Organization (WHO) warns about a potential avian flu pandemic worldwide. In such a case, the pandemic will possibly kill 51 to 81 million people (WHO, 2009). Facing the threat, former President Bush unveiled a $7.1 billion emergency plan on November 2, 2005 to make antiviral drugs available for more Americans. By October 2008, US international support to fight the pandemic totaled $949 million (US Department of Health and Human Services, 2009). Thus, bird flu news stories provide a desirable context because the threat of a bird flu pandemic to America is real.

In past activation research, a great deal is known about the relations between message sensation value and sensation-seeking on outcome measures such as attention, arousal, fear, and behavior intention (Donohew, Palmgreen, & Duncan, 1980; Everett & Palmgreen, 1995; Lorch et al., 1994; Palmgreen, Donohew, Lorch, Hoyle, & Stephenson, 2001), but relatively little is known about the relations between message sensation value and viewer perception of media messages. Scholars have raised the question whether message sensation value in media messages may distract target audiences in communicating health threats (Stephenson & Southwell, 2006). They have a concern that some audience members may be stimulated by arousing messages but fail to get the message. Unfortunately, there is no research to address this concern to date.

To fill the gap, the dependent measures of message sensation value were expanded in this study by including perception of news stories. That is, how stories with varying levels of message sensation value in bird flu TV news stories were evaluated by the target audience. The perception of the stories focused on the dimensions of clarity, understandability, and professionalism. Practically, little is known about Americans' preparedness for a bird flu pandemic. How do Americans process bird flu news? Will they view bird flu as a serious threat to America after viewing the bird flu news stories? And will they likely seek information to get prepared as a result of exposure to the stories? Findings will provide valuable information for public health agencies in policymaking.

The Activation Theory of Information Exposure and Hypotheses

As mentioned earlier, the activation theory of information exposure holds that, when attending to a message, one seeks to satisfy one's need for stimulation and information. But, one will seek to fulfill the need for stimulation prior to the need for information (Donohew, Palmgreen, & Duncan, 1980). The theory is grounded in the assumption that individuals have levels of arousal at which they are most comfortable. It further proposes that a message will likely attract an individual's attention if the message provides optimal arousal to satisfy his or her need for stimulation (Donohew, 1990; Donohew, Lorch, & Palmgreen, 1998). Kroeber-Riel (1979) defined activation as part of human behavior that elicited arousal and inner tension to enable "psychological and motor activity of the organism (p. 241)." Conceptually, the need for stimulation is a kind of personal trait like sensation-seeking (Christ, 1985; Donohew, 1990). Sensation seeking, according to Zuckerman (1979), is, "a trait defined by the need for varied, novel, and complex sensations and experiences, and the willingness to take physical and social risks (p. 10)." Christ (1985) proposed that arousal need is one of the psychological mechanisms which motivates individuals to process information.

Therefore, the activation theory of information exposure is concerned with audiences' psychological processes; it also focuses on audience characteristics (e.g., differences in need for arousal) and message features (e.g., stimuli) in producing effective media messages (Cappella, 2006; Donohew, 1990). Empirically, Donohew, Palmgreen, and Duncan (1980) examined the relationships among needs for activation, importance of information, discrepancy, and effects of that information. Using Pearson's Novelty Experiencing Scale as a measure of arousal need, they found that among participants with a high need for activation, unimportant information in newspapers produced a negative effect; but, information on an important newspaper story, that simulated subjects to meet their activation needs, generated a positive effect.

Lorch and her colleagues (1994) conducted an experiment to examine the effects of message and program sensation value, sensation seeking, and drug use on visual attention to televised anti-drug PSAs. The experiment examined adolescents. Results showed that attention to an anti-drug PSA was higher if the PSA was placed in a program context where the sensation value of the program was optimal for subjects (both high-sensation seekers and low-sensation seekers). Applying the activation theory to an anti-cocaine campaign, Everett and Palmgreen (1995) investigated the effectiveness of sensation seeking, message sensation value in PSAs, and program sensation value to free/cued recall of messages. They also investigated attitudes toward cocaine and behavioral intention to use cocaine. Results demonstrated that high-sensation seekers appeared to be more affected by the PSAs' high-sensation value than low-sensation value; they tended to recall more, have more negative attitudes to cocaine, and self-reported less likelihood to try cocaine. Lowsensation seekers were more affected by the PSAs' low-sensation value message. They also recalled more, had a negative attitude toward cocaine, and indicated a less likelihood to use cocaine. Recent studies (Lang, Schwartz, Chung, & Lee, 2004; Morgan et al., 2003; Palmgreen et al., 2001; Palmgreen, Donohew, Lorch, Hoyle, & Stephenson, 2002) show new evidence that PSAs, with high-sensation value targeting teen high-sensation seekers, would be effective in drug prevention.

The review of the literature provided the grounding based on which the following hypotheses were formulated:

H1: Participants would pay more attention to bird flu TV news stories with high message sensation value than those with low message sensation value.

H2: Participants would register more arousal to bird flu TV news stories with high message sensation value than those with low message sensation value.

H3: Participants would report greater fear to bird flu TV news stories with high message sensation value than those with low message sensation value.

H4: Participants think that a bird flu outbreak would affect more lives in response to bird flu TV news stories with high message sensation value than to those with low message sensation value.

H5: Participants would report higher behavioral intention in response to bird flu TV news stories with high message sensation value than those with low message sensation value.

Finally, message sensation value in broadcasting news stories has the potential to contribute to higher ratings. It will be interesting to study if, and how, stories with varying levels of message sensation value affect participants' perception of the stories. A research question was raised:

RQ: Will participants perceive differently bird flu TV news stories with high message sensation value from those with low message sensation value?

Method

This study employed a repeated measure 2 (MSV) x 2 (Sensation-seeking) x 4 (stories), within subject factorial design, to test the hypotheses. The three factors of this experiment were message sensation value (high and low), sensation-seeking (high, low), and four bird flu TV news stories, which were held as a repeated measure. Message sensation value is a within-subject factor, whereas sensation-seeking is a between-subject factor. The advantage of this mixed design was to rule out topic influence by having all participants viewing all four stories. In addition, two presentation orders were created to randomize primacy and recency effects.

Participants

A number of bird flu TV news stories were acquired from CNN PathFire. All of them focused on bird flu as a public health threat. Four stories were chosen based on the varying level of five factors: graphic effects, emotional intensity, unusualness, dramatic impact, and sound effect. Two stories were judged to be high in message sensation value, whereas, the other two were low in message sensation value. To ensure successful stimuli production, manipulation checks were conducted using a separate pool of participants from the main study. A total of 46 undergraduates evaluated the stories using the 17-item perceived message sensation value scale (Palmgreen, Stephenson, Everett, Baseheart, & Francies, 2002). T-tests revealed that message sensation value between the two sets of stories was significant (t=35.52, p < .01). Stories considered to be high in sensation value were rated significantly higher (M=4.20, SD=.62) than stories considered to be low in sensation value (M=3.62, SD=.69). (1)

For the experiment, 54 participants were recruited from a large Southeast university research participant pool. Participants in this study ranged from 18 to 42 in age, with a mean of 21 years. In terms of gender, 35% of the participants were male, and 63% were female, with one person's gender data missing.

Procedures

Upon arrival, participants were greeted and taken into the lab. They were told that they would be completing an experiment about how people process news stories. The procedures for measuring heart rate and skin conductance were explained at this point. All participants were given informed consent statements to read and sign. The participants completed the 40-item SS (Sensation-seeking) scale designed to measure predisposition toward sensation seeking. The participants then watched the four featured CNN TV news stories about bird flu, ranging in duration from two minutes and 20 seconds to two minutes and 41 seconds. Physiology data was collected while the participants watched. Following each news story, the stimulus and physiology data collection was stopped. Participants filled out self-report measures of story perception, fear, perceived effects, valence, and arousal, as well as behavioral intention in response to the story just viewed. When participants were ready to move to the next story, physiological data collection began again. This procedure was repeated for all four stories. After participants completed measures for all four stories, they were thanked, debriefed, and dismissed. Physiological data was recorded with the BioPac MP150 modular data system. ECG (electrocardiogram) and skin conductance or electrodermal activity (EDA) input was amplified by the MP150 and fed into a Dell Inspiron 1150 laptop computer. Heart rate was measured initially as milliseconds per beat, and then transformed into average heart rate per second. Skin conductance was collected as an analog signal with a sample rate of 20 times per second.

Dependent Measures

Attention

Attention was measured by heart-rate monitoring of cardiac deceleration. Heart rate can reveal details about a subject's attention and cognitive states, as the heart is under the control of the sympathetic and parasympathetic systems of the autonomic nervous system. When one pays attention, the parasympathetic system slows down the heart. In this study, cardiac deceleration was the basis for measuring short-term changes in attention to stimuli. Arousal

Arousal was measured by self-reported data using the pictorial SAM (self-assessment mannequin) scale (Lang, Dhillon, & Dhong, 1995), as well as with skin conductance data (Hopkins & Fletcher, 1994). SAM is a three-dimensional, pictorial, emotional-rating scale with nine rating points. Participants rated their emotional responses in terms of arousal (calm-excited), valence (positive-negative) and dominance (small-in control). Only the arousal dimension was used. Electrodermal activity (EDA) in test participants was used to measure arousal in response to a stimulus (Stern, Ray, & Quigley, 2001). Skin conductance has been recorded in numerous psychophysiological studies (Stern et al., 2001), dating as far back as research conducted by Carl Jung in 1907. Changes of skin conductance in participants occur as they respond to the stimuli and the variation is in direct proportion to the message's intensity of emotion. Conductance variation in amplitude exceeding .5 uS (micro Siemen) was counted as a response.

Fear

Four items using a 7-point semantic differential scale were created to measure fear. The items measured whether the participant felt overwhelmed, fearful, uneasy, and apprehensive, after watching the story. Reliabilities (Cronbachs' [alpha]) for the scales across the four stories ranged from .87 to .91, with an average of .89. For each story, responses were therefore summed and divided by five to create a mean response for each participant. In addition, a single item was also included in the study to gauge participants' fear of how serious a bird flu pandemic would be.

Story Perception

Eight items using a 7-point semantic differential scale were created to measure participants' perception of bird flu TV news stories. The items measured whether the story was appealing, clear, understandable, enjoyable, stimulating, credible, engaging, and informative, with a low score representing low perception of the story. Reliabilities (Cronbachs' [alpha]) for the scales across the four stories ranged from .76 to .88, with an average of .82. For each story, responses were therefore summed and divided by eight to create a mean response for each participant.

Behavioral Intention

Four, 7-point, Likert-type items were created to measure participants' behavioral intention. The four items were, "I need to learn more about bird flu," "I am going to pay close attention to bird flu," "I am going to do everything possible to help my community prepare for bird flu," and "I am going to do everything possible personally to stay off the pandemic." Reliabilities (Cronbach'[alpha]) for the scales across stories were rather high, ranging from .82 to .88, with an average of .85. For each story, responses were therefore summed and divided by four to create a mean response for each participant.

[FIGURE 1 OMITTED]

Results

To test the hypotheses, six, two-way, repeated ANOVA tests were performed. H1 predicted that participants would pay more attention to bird flu TV news stories with high message sensation value than those with low message sensation value. The main effect for attention was significant, F (1, 52) = 5.77, p < .05, [[epsilon].sup.2] = .10 (see Figure 1). Participants did pay more attention to bird flu TV news stories high in message sensation value, as indicated by lower heart rates (M = 73.67, SD = 1.42) than to those lower in message sensation value (M = 76.89, SD = 2.4). H1 was supported.

H2 predicted that participants would register more arousal to bird flu TV news stories with high message sensation value than those with low message sensation value. Arousal was inferred from physiological measurement of skin conductance. The main effect for arousal was significant, F (1, 52) = 4.57, p < .05, [[epsilon].sup.2] = .08. Participants were more aroused when watching stories higher in message sensation value, as indicated by the higher number of skin conductance responses (M = 9.12, SD = 1.02), than watching those lower in message sensation value (M = 7.38, SD = 0.83). Self-reported arousal as measured by SAM, however, did not triangulate the physiological responses: F (1, 52) = 3.67, p = .06, [[epsilon].sup.2] = .06. Participants' reported arousal when watching the stories high (M = 9.12, SD = 1.02) and low (M = 7.38, SD = 0.83) in message sensation value did not differ significantly, even though it was approaching significance. H2 was partially supported. (2)

H3 predicted that participants would report greater fear of bird flu with TV news stories of high message sensation value than those with low message sensation value. The main effect for fear was significant, F (1, 52) = 35.73, p < .01, [[epsilon].sup.2] = .40. Participants were more apprehensive of bird flu after watching stories higher in message sensation value (M = 3.90, SD = 0.15) than after watching those lower in message sensation value (M = 3.20, SD = 0.13). H3 was supported.

H4 proposed that participants would think the bird flu would affect more lives in response to bird flu TV news stories with high message sensation value than to those with low message sensation value. The main effect for such perception was significant, F (1, 52) = 12.00, p < .01, [[epsilon].sup.2] = .19. Participants considered bird flu would affect many lives in response to stories higher in message sensation value (M = 4.23, SD = 2.21) than after watching those lower in message sensation value (M = 3.70, SD = 2.22). H4 was supported.

H5 predicted that participants would report higher behavioral intention in response to bird flu TV news stories with high message sensation value than those with low message sensation value. The main effect for behavioral intention was significant, F (1, 52) = 5.17, p < .05, [[epsilon].sup.2] = .09. Participants intended to learn more about and better prepare for bird flu after watching the stories high in message sensation value (M = 4.40, SD = 0.17) than after watching those low in message sensation value (M = 4.16, SD = 0.17). H5 was supported.

Finally, the RQ asked if participants would perceive differently bird flu TV news stories with high message sensation value from those with low message sensation value. The main effect for perceptions was significant, F (1, 52) = 66.03, p < .01, [[epsilon].sup.2]2 = .56. Participants reported better and more positive perception of stories high in message sensation value (M = 5.24, SD = 0.65) than those low in message sensation value (M = 4.57, SD = 0.43). The perceptions included clarity, understandability, credibility, enjoyability, engagement, and informative ness.

Discussion and Conclusion

This investigation applied the activation theory of information exposure to understand how message sensation value in the public health context affected the effectiveness of the news stories about the bird flu pandemic. All five of the hypotheses were supported. Message sensation value seemed to be the key factor influencing participants processing of the stories. It had main effects on all of the five, dependent, outcome measures, including attention, arousal, fear, apprehension about the massive impact of a bird flu outbreak, and behavioral intention.

More importantly, new research ground was broken in the current study. Some scholars are concerned that message sensation value may be a distraction in communicating public health threats to target audiences (Stephenson & Southwell, 2006). Audience perception of stories was incorporated as a dependent measure (e.g., perception of the clarity, understandability, and professionalism of the stories), and how it was related to message sensation value was examined. Findings show that message sensation value affected story evaluation in a positive fashion: the higher the message sensation value, the more positive the perception of the story in terms of clarity, understandability, credibility, being enjoyable, engaging, and informativeness. Thus, message sensation value is not a distraction in bird flu TV news stories, but a facilitator of participants' processing. This finding contributes to the research of activation theory of information exposure.

But the mechanism that explains how message sensation value, story evaluation, and other message effects impact one another was not examined in this study. For instance, does message sensation value affect story perception, which in turn impacts arousal? Or, does message sensation value affect arousal, which then impacts story perception? Ascertaining the interrelationships among these variables is clearly a new direction for future research.

The activation theory of information exposure explains how bird flu news with message sensation value, a device in communicating public health threats, has had effects on audiences in getting their attention to the pandemic, being aroused, and fearing the impact of an outbreak. In addition, the effect of message sensation value on subjects' behavioral intention was found. After watching the bird flu news stories that were high in message sensation value, participants are more likely to get prepared. These findings suggest that Americans took the bird flu threat seriously and would get prepared. News organizations play a critical role in helping the American public prepare for bird flu pandemic.

Findings of this study are subject to limitations of use of a student sample, which was relatively homogenous and skewed toward females. Future research can expand the current study to a larger sample drawn from the general public, which will likely provide more appropriate data to test the interaction effect between the message sensation value in bird flu news stories and the sensation-seeking trait of subjects. In addition, more news stories from varied sources can be used to replicate the current study.

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Notes

(1) One story is about how the US would fare and respond if a bird flu pandemic broke. The reporter put on a facemask and led his viewers to the USDA's biggest lab in Ames, Iowa, where scientists were working frantically to come up with a vaccine. Another story featured Indonesia as the center of the pandemic, where more birds died than at any other place in the world. These two stories were in the high message sensation value level. At the low end of this manipulation were a story about how a Florida community was preparing to round up chickens running loose in the city, where residents argued that the city council is just using bird flu as an excuse to get rid of the chickens. Another story opened with a chicken vendor in Hong Kong complaining about a hard time making a living because people were afraid of eating chickens; the story wrapped up by praising Hong Kong as being the gold standard by WHO to combat bird flu.

(2) Two factors might be at work here: the effect size of arousal is small anyway, so the nuances may be lost between these two measures. Physiological measures were more sensitive than self-report data, as participants may have a hard time evaluating their emotion. This issue can be further explored in follow-up methodological studies.

Ran Wei, University of South Carolina

Shuhua Zhou, University of Alabama

Correspondence:

Ran Wei, Ph.D.:

Professor

School of Journalism & Mass Communications

University of South Carolina

Columbia, SC 29208

Tel: (803) 777-5762; Fax: (803) 777-4103

E-mail: wei2@mailbox.sc.edu

Shuhua Zhou, Ph.D., Associate Professor

Department of Telecommunication & Film

College of Communication & Info. Sciences

University of Alabama

Tuscaloosa, AL 35487-0152

Office: (205) 348-8653; Fax: (205) 348-5162

E-mail: szhou@bama.ua.edu
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