Relationship Between Rage Tendency and Body Conditions

Abstract

This paper analyzes the relationship between the easiness to get raged and physical conditions associated with recall process of past memories. We tested if the easiness to get raged can be detected using measurement of physical conditions in such situations. The results indicate that it is possible, particularly for females.

1 Introduction

This paper investigates the body conditions particular to persons that are easier to get raged and those who are not. Here we denote rage as violent anger or angry fury, stronger than the anger, often accompanied by physical aggressions. Statistics indicate that rage incidents are increasing. The familiar term “road rage” denotes aggressive driving and maneuvers against other cars while driving a car. A different statics in Japan indicates that elementary school students’ violent acts have increased about fourfold in ten years from 2008 to 2017.

This work investigates extreme anger, and anger constitutes one of six basic emotional states. Estimation of emotional states, particularly of the six basic emotional states, has been investigated since the beginning of psychology [1]. Particularly the study to elucidate the relationship of the basic emotional states with autononomic nervous system has been active. As one of six basic emotional states, several studies on anger have been published. However, no study treated more extreme cases of anger or blowups, and no studies on relationship with physical conditions have been published. This paper analyzes the influences of rage on body conditions, namely ECG (electro cardiogram), EEG (electro encephalogram) and EDA (electro dermal activity).

There seems to be a correlation between the personality related to aggression and cardiovascular reactivity. Izawa et al. reported the result of survey with twenty undergraduate students [2], where the aggression was related with the increase of the systolic blood pressure and diastolic blood pressure at the time of provocation, rise in systolic blood pressure at rest after provocation, and association between reduction of systolic blood pressure and diastolic blood pressure.

Klimecki et al. conducted a subject experiment using an unequal economic game to anger the subjects [3]. Three subjects played the game, consisting of one participant and two experimental collaborators. The actions of two cooperators were determined in advance, instructed to take only the actions that benefit themselves and harm the participant. Initially, most participants were equally distributing profits to the two cooperators, but when one collaborator began provocative acts, some participants took “revenge actions” to provoke the collaborators. Brain activities were measured by using fMRI to analyze the “revenge” factor in contributors. They found that the participant was feeling anger, and the dorsal prefrontal cortex, denoted the ceremonial command tower, which plays a role in cognition, motivation and judgment, was active. The temporal lobes of the brain and the amygdala also were active.

There is a study on the relationship between anger and brain activity and physical condition [4]. It was reported that the brain activity of the left forehead became dominant and the heart beat rate increased. This study classified methods to induce anger in the experiment, (1) natural situation, (2) recall of personal events, (3) induction by facial expressions, (4) image guidance, (5) insults, and (6) provocations.

The details of these methods are as follows.

• 1. Instruct experiment collaborators to take harassing behaviors to participants, such as taking abusive attitude towards subjects.

• 2. Listen the upsetting events beforehand from the participants. Read out these events to the participants, forcing them to remember the event.

• 3. Experiment collaborators create facial expressions of intended emotion, inducing these emotions to the participants.

• 4. Present photos of the International Affective Picture System (IAPS) to evoke various emotions.

• 5. Instruct the experiment collaborators to write insulting comments to the text preliminarily written by the subject. Then let the subject read the comment to evoke anger.

• 6. Provoke directly the participants, by instructing the experiment collaborators to answer sentences like “I cannot hear” even if the participants say in loud voice.

There is a study on autonomic nerve responses during psychological stress and palmar perspiration [5]. This study investigated the amount of perspiration in healthy subjects’ palms at normal and mental stress (mental arrhythmias, bicycle exercise) load, and analyzed autonomic nerve responses (blood pressure, electrocardiogram) and sweating of the palm. Quantitative analysis indicated that the heart rate, the systolic blood pressure and the diastolic blood pressure, and the sweating amount of the palm significantly increased under the mental load.

Some studies have used personalized recall to induce anger, and reported relationships with autonomous nervous systems [6,7,8,9,10,11]. However, these studies focused on the activity patterns of autonomous nervous systems when participants were in anger state, and no study investigated the relationships with past experiences.

2 Methods

This paper tested the following hypothesis.

• 1. The changing behavior of body conditions depends on the existence of raging experiences by the participant.

• 2. The changing behavior of body conditions also depends on gender.

Experiment was conducted with two groups of participants, each consisting of five males and five females, totaling twenty participants. The difference of the two groups is if they had raging experience in the past or not.

Therefore, the participants whether belonged to Group-A with raging experiences or Group-B without raging experiences. Obviously the raging experiences were participants’ personal experiences, and the judgment of that experience as raging or not is also personal. On the other hand, there are no methods to verify the existence of rage in participant’s life except direct interview with sincere answer. However, since there are no definitive methods to verify each participant’s claims, we used this classification. Although the interpretation of the experience and its classification as raging or not is personal and not standardized, at least the integrity inside the person is assured. The point is whether a person interpreted the experience as raging or not. It is difficult to control the evaluation criteria if the experience is raging among all participants. Furthermore, the experience is personal, and “virtual” experience is more realistic to the participant than reading or listening descriptions of raging situations, as the participants confront images when recalling past experiences.

The experiment was conducted in the following sequence.

• 1. Rest for two minutes

• 2. Remember happy moments for eight minutes

• 3. Rest for two minutes

• 4. Remember raging (Group-A) or unpleasant (Group-B) moments for eight minutes

• 5. Questionnaire

The experiment aims to measure the physical conditions when participants are in raged condition. Therefore, the ideal experiment would be to put literally the participants in raged conditions. However, since the raging experiences involve breaking or throwing things and physical violences, we took an indirect approach to force the participants to recall their experiences, emulating their experiences internally. We assume that emotional aspects can be reconstructed without body movements, at least partially. This method is similar to “recall of personal events” described before, the second method introduced in [4]. The participants explain details of incidents that made them angry before the experiments, and the experiment collaborator reads out the content. However, we asked the participants to remember their experiences and did not request their explanations, because the experience was painful for the participants and may cause extreme emotion and unpleasantness.

The body conditions were measured during the whole experiment, from the beginning to the end. ECG, EEG and EDA were measured using Bitalino(r)evolution. The two rest stages (stages 1 and 3) are used as the control condition to be compared with stages recalling happy moments (stage 2) and raging or unpleasant moments (stage 4).

The physical condition values were analyzed using relative values based on the control condition (rest stage), as the individual variability of these values were high. Additionally, the relative value between happy and raging was also calculated.

Thus the following relative values were calculated: (i) rage minus rest; (ii) happy minus rest; (iii) rage minus happy. These conditions were analyzed between the Group-A and -B, and the gender difference was also analyzed.

Figure 1 is an example of physical conditions measurement.

3 Results and Discussions

We analyzed the results of the whole participant groups and separately based on gender to the two hypotheses, as the both Group-A and B consists of equal number of male and female participants. In both EDA and ECG measurements, we analyzed the relative values, since the absolute values of both measurements are highly participant dependent, and direct comparison of absolute values among participants is of little value. Therefore, the following three relative values were calculated: (1) relative value of happy moments, which is the difference between the happy moments and resting stages; (2) relative value of raging moments, which is the difference between the raging moments and resting stages; and (3) difference between raging and happy moments. The first two values are the values relative to the control condition.

Fig. 1.

Example of a measurement result with Bitalino(r)evolution

We found that the EDA and ECG are possible indicators to classify persons that are likely to get raged or not, as there were differences with significance in these measurements. Specifically, the participants of Group-A and Group-B showed different body condition changing behavior.

Figure 2 shows the results of EDA measurements. Since EDA values are strongly person-dependent, we calculated relative EDA values of raging and happy moments by subtracting the values of the resting condition values, using the latter as the control condition. The value of raging moments relative to the value of happy moments was also calculated.

Figure 2 indicates that the Group-A and -B have different relative value changing patterns, as the Group-A showed positive relative values in all three analytical conditions, i.e., happy minus resting stage, raging minus resting stage and raging minus happy stage. On the other hand, the Group-B showed negative relative value in raging minus resting stage and raging minus happy stage, and negligible difference in happy minus resting stage. Group-A has higher EDA values in all cases, suggesting that persons with raging experiences show stronger EDA variations, or more direct expressions.

Fig. 2.

Results of EDA measurements

Fig. 3.

Results of HR measurements. Mean HR and maximum HR.

The heart beat rate was calculated from ECG data. The maximum and the average rates were used for the analysis. Figure 3 shows the results of HR measurements. Analogous to EDA analysis, we calculated relative HR values of raging and happy moments by subtracting the values of the resting condition values, using the latter as the control condition. The value of raging moments relative to the value of happy moments was also calculated.

Both Group-A and -B showed increase of HR when rise in emotion was observed, with slightly higher values of happy images than raging moments, although very small and this difference had no statistical significance. The mean HR and maximum HR values showed similar value changing patterns among the happy, raging and resting conditions, where the HR value of both happy and raging moments were higher than the resting condition, which is in accordance with other studies. Moreover, the Group-A showed equivalent HR values between raging and happy moments. However, both mean and maximum HR of happy moments were higher than raging moments in Group-B participants, suggesting that the image of happy moments was clearer than raging moments, since the Group-B consists of participants without extreme anger experience, and it is possible that their anger or irritating memories were not so strong, resulting in not so high HR.

When measured with HR, Fig. 3 suggests that the strength of happy moments is high, as both mean and maximum HR were approximately identical in Group-A, as the raging memories of the participants of Group-A were strong. Surely the raging moments consist of possibly negative emotions, which is opposite to happy moments that consist of positive emotions. However, the strength of the influence on HR is identical.

Only the maximum HR of rage minus control condition had statistical significance, and there was no significance in average HR values.

3.1 Gender Differences

Significant differences were observed between male and female participants, as the body condition changes were different. Figure 4 shows the relative values of EDA of male and female participants. The changing pattern is different for Group-A and -B of male and female. For Group-A male participants, the value of raging moments was the highest, followed by happy and resting stages, as in all three relative value conditions (happy−rest, rage−rest, and rage−happy) the values are positive. On the other hand, the value of rage−happy condition is negative for Group-B male participants. Furthermore, the values of happy−rest and rage−rest of Group-A are higher than those of Group-B.

On the other hand, EDA of female participants showed different relative value changes than male participants. Similar to male participants, all three values were positive (happy−rest, rage−rest, rage−happy) for Group-A, but all negative for Group-B, suggesting the opposite mechanism that affect the EDA. Moreover, EDA during raging moments was higher than happy moments in Group-A, but happy moments was higher in Group-B.

The changes were more evident in females, as there was statistical significance. On the other hand, no changes with statistical significance were observed in male participants.

Fig. 4.

Results of EDA measurements. Male and female subjects.

Figure 5 shows the difference of HR response for male and female participants. Both male and female participants had different value change patterns from the genderless measurement results shown in Fig. 3. This discrepancy is normal, as the average, which is the genderless group analysis in this case, is different of components (male and female groups) that constitute the whole group [12]. In both male and female cases, the happy and raging moments result in higher HR than the resting condition for Group-A. The difference, however, appears in comparison between raging and happy moments, where the raging results in higher mean HR for males, and lower for females. The HR values of Group-B are also different for males and females. The mean HR of raging moments is lower than the resting and happy moments for males of Group-B. On the other hand, raging moments result in a slightly higher average HR for females of Group-B. Since Fig. 5 is the mean HR, we also analyzed the peak HR, which reflects instantaneous response and thus clearer influence can be observed.

Fig. 5.

Mean HR values. Male and female subjects.

Figure 6 shows the difference of maximum HR for male and female participants. Similar to the mean HR case (Fig. 5), both male and female participants had different value change patterns from the genderless measurement results.

Both male and female participants had different value change patterns of HR (Figs. 5 and 6) from the genderless measurement results shown in Fig. 3. The male participants of Group-A had high maximum HR for raging moments, followed by happy moments. On the other hand, less similarity was observed between male and female participants of Group-B. The maximum HR of the resting condition of female participants was the highest, and raging moments resulted in the lowest HR. This lower HR of raging moments than happy moments was also observed in male Group-B participants.

Fig. 6.

Maximum HR values. Male and female subjects.

Table 1 summarizes the factors with statistical significances.

Table 1. Statistical significances of measured features

4 Conclusions

The present study aims to clarify the rage and physical conditions. The results indicate that the physical conditions change differently for persons with raging experiences and those without. The experiments presented in this paper is useful to detect in advance if the person is likely to get raged or not.

We found that the EDA and ECG are possible indicators to classify persons that are likely to get raged or not, particularly for females.

Based on these results, the following test can be used to classify a person. A person is asked to recall (1) happy moments, (2) raging or unpleasant moments, measuring EDA and ECG. Then the likeliness of the person to get raged can be predicted according to the relative values among happy, raging and resting moments and the patterns of the value changes.