Abstract
Toilet activities of the elderly patients with dementia were observed focusing on care conditions and investigated based on Hull’s drive reduction theory (behavior = drive × habit × incentive) and our self-awareness model (consisting of theory of mind, self-evaluation, and self-consciousness) to evaluate the association between self-awareness and toilet activities in patients with dementia and to explain the time when and the reason why a series of toilet activities as habit once acquired become unfeasible. If theory of mind is lost, awareness of one’s desire and intention becomes vague, and toilet activities begin to collapse. Furthermore, if incentive disappears, one’s intention hardly arises and toilet activities further collapse. If self-evaluation is lost, time sense fades, future goals based on the present time cannot exist, and behavior loses directivity. As a result, toilet activities collapse, and with a decrease in drive toilet activities cease.
Keywords: dementia, motivation, self-awareness, self-consciousness, self-evaluation, theory of mind, toilet activities
Introduction
The basis of care is to know the needs of patients. It is quite possible to understand the needs of patients who maintain cognitive functions. However, it is difficult to understand the needs of people with dementia who use puzzling words and perform perplexing deeds. If caregivers are unable to understand the needs of people with dementia, the caregivers cannot provide appropriate care, leading to an increase in the caregivers’ sense of burden and distress, and thus, care falls into a vicious cycle. It is essential to understand the needs of people with dementia in order to break the vicious cycle of care. In recent years, there have been attempts using interviews to ask people with dementia directly whether their needs in daily life are met. 1–4 Although this point of view is important, this method has obvious limitations for people with dementia who are vaguely aware of their own minds and conditions. On the contrary, to understand the needs of people with dementia in daily life, the major question should be why help became needed in the first place.
Therefore, this study investigated when and why people with dementia become unable to perform certain activities of daily living, that is, toilet activities, 5–8 which are a major cause of caregivers’ sense of burden and trigger of institutional placement.
The causes of actions such as excretion used to be explained by the concept of instinct, but the concept of instinct is vague and not scientific. Therefore, Woodworth 9 used humans and animals to resemble machines and defined “drive” as the power to move machines. 10 Drive is a hypothetical concept generated by the necessity of explaining why behavior is induced by biological needs such as hunger, thirst, and excretion. 11 Namely, drive denotes the state required to induce any behavior inside of individuals or energy. 12 Human behavior sometimes occurs based on intrinsic motivation by curiosity and interest. However, since toilet activities were analyzed in this study, the study was based on Hull’s drive reduction theory, 13 which was developed according to minute animal experiments to explain the mechanisms by which biological needs for survival (such as hunger, thirst, excretion, and respiration) induce behavior.
Influenced by Cannon’s concept of homeostasis, Hull 13 grasped that the behavior of an organism is the response of the organism to maintain homeostasis and concluded that it can be explained as a product of drive, habit, and incentive (behavior = drive × habit × incentive). Namely, Hull considered that behavior is initiated by drive, that is, energy generated from the state of collapsed homeostasis, maintained, oriented by past habits, and reinforced by incentives (rewards such as feed), and that drive is reduced by obtaining incentives (drive-reduction theory). 13 Drive and habits cannot be directly observed, and whether or not one is motivated is judged by whether or not the behavior is actually initiated, maintained, and oriented. 14
In addition, the reasons why a series of activities, which are acquired habits, become unfeasible and the puzzling behavior arises in people with dementia have so far been explained by apraxia, agnosia, and individual intellectual functions such as memory, judgment, and orientation. 15–20 However, dementia is not a state in which disturbances of intellectual functions, such as memory impairment, impaired judgment, and disorientation, are aggregated but is a state in which the intellectual subject integrating these intellectual tools is harmed. 21 Consequently, people with dementia cannot be understood by examining individual intellectual functions. 22 Therefore, we created a model for interpreting puzzling words and deeds of people with dementia from the viewpoint of self-awareness, which is the intellectual subject 23–26 (Figure 1). This model consists of “a developmental model of cognition and emotion” by a developmental psychologist, Michael Lewis, 27–29 and “theory of mind” by psychologists Wimmer and Perner 30 (Figure 2).
Figure 1.
A model for interpreting puzzling words and deeds of people with dementia from the viewpoint of self-awareness.
Figure 2.
Interrelated development of cognition and emotion and theory of mind. Adapted from Lewis’s developmental model of cognition and emotion, and Wimmer’s and Perner’s theory of mind.
According to Lewis, humans have emotions of “contentment,” “curiosity/interest,” and “distress” when they are born, and emotions of “joy,” “anger,” and so forth diverge from them and develop in relationships with others. At an age of approximately 1.5 years, “self-consciousness” arises which makes infants aware of their own presence and allows them to distinguish between self and others, and emotions of “empathy” and so on develop. At an age of 2.5 to 3 years, they acquire the “self-evaluation” function that allows them to understand the standards and rules of the society in which they live and to judge whether their thoughts and actions are good or bad in comparison with the standards. As a result, the emotions of “shame” and “guilt” develop. In addition, humans assume mental action against the background of others’ behavior, 31 and Wimmer and Perner 30 revealed that children aged 4 to 6 years acquire the “theory of mind,” 32 which is the ability to estimate psychological states (intention, thought, belief, desire, emotion, preference, etc) that are in the background of their own and others’ behavior and cannot be directly observed. That is to say, infants become able to distinguish between themselves and others by the emergence of “self-consciousness,” begin to prepare to adapt themselves to the standards of the society by the acquisition of “self-evaluation,” and estimate the minds of others to adapt themselves to relationships with many and unspecified people by “theory of mind.” Put in another way, the development of these self-awareness processes is the basis for humans to adapt themselves to complicated human relationships.
In the current evolutionary theory, the widely accepted social intelligence hypothesis explains that the evolution of “intelligence” was not caused by the fact that humans were tool makers but caused by the necessity for humans to adapt themselves to complicated human relationships, such as cooperation and negotiation with other individuals. 33–35
Our model perceives that dementia is a disease in which patients become unable to adapt themselves to complicated human relationships and follow a process opposite to that observed in infants when adapting themselves to complicated human relationships.
Based on the previous concept, we considered that the time when and reason why a series of toilet activities become unfeasible in patients with dementia can be explained using Hull’s drive-reduction theory and our self-awareness model.
The purpose of this study was to evaluate the association between self-awareness and toilet activities in patients with dementia and explain the time when and the reason why a series of toilet activities as habits once acquired become unfeasible. For this purpose, toilet activities in the elderly patients with dementia were divided into 10 steps and observed focusing on care conditions. The toilet activities observed were placed in order from the viewpoint of motivation (initiation, maintenance, and orientation of activities) and investigated based on Hull’s drive-reduction theory 13 and our self-awareness model. 23–26
Methods
Participants
The study involved a group of 21 participants. They were selected among residents of a nursing home. Of the 80 residents there, 21 participants (5 males and 16 females; mean age, 86.8 ± 4.9 years) were diagnosed with dementia and used a toilet for their toilet activities.
The diagnoses in the participants with dementia were Alzheimer’s disease (17 participants), cerebral vascular dementia (3 participants), and frontotemporal dementia (1 participant).
They had a medical history of cerebral infarction (10 participants), bone and joint diseases (9 participants), heart diseases (5 participants), respiratory diseases (3 participants), diabetes (3 participants), hypertension (6 participants), and cancer diseases (3 participants).
All the participants had incontinence; 8 participants had urinary incontinence, and 13 had both urinary and fecal incontinence.
For ethical considerations, this study was conducted with the approval of the ethics committee of the facility and consent of the participants’ families.
Assessment Conditions
Observation of the toilet activities of the participants and evaluation of their self-awareness ability were performed as follows.
Observation of Toilet Activities
According to the following 10 steps of toilet activities described by Yamane and Tsuchijima, 36 the first author observed and recorded the participants’ daily toilet activities:
(1) Moving from the day room; (2) entering the toilet; (3) undressing (taking off trousers and shorts); (4) sitting on the toilet seat; (5) excretion (urination and defecation); (6) cleaning-up (wiping); (7) standing up from the toilet seat; (8) clothing (wearing trousers and shorts); (9) coming out of the toilet; and (10) returning to the day room.
Evaluation of Self-Awareness
“Theory of mind,” “self-evaluation,” and “self-consciousness” were evaluated by the first author and a coauthor, a physical therapist in the facility. The evaluation was performed in a quiet place, considering the maintenance of the participants’ attention and the degree of their hearing loss.
Assessment of the presence or absence of the theory of mind
The authors sat on a table opposite to a participant and placed 4 picture cards (Figure 3), in which the “false-belief” task by Wimmer and Perner 30 was clearly illustrated based on the figures drawn by Muto, 37 side by side on the table. Next, after confirming that the participant was watching the cards, the authors slowly read out the explanation of Figure 3, with a finger pointing to the cards 1 to 4 one by one. If the participant chose the round box, he or she was judged to have the “theory of mind.”
Figure 3.
The 4 picture cards to evaluate the presence and the absence of theory of mind. Scene 1: there are a round box and a square box in front of Taro and Hanako. A bean-jam bun is contained in the round box. Scene 2: Taro is leaving the room. Scene 3: in the meantime, Hanako has transferred the bean-jam bun from the round box to the square box. Scene 4: Taro has come back. In which box, the round box or the square box, does Taro think the bean-jam bun is?
Assessment of the presence or absence of self-evaluation
Since Lewis had shown no method of assessing the presence or absence of “self-evaluation,” we created 4 pairs of picture cards for assessing the understanding of the basic standards and the rules of the Japanese society (Figure 4). 23–26 The authors sat on a table opposite to a participant and placed these 4 pairs of picture cards on the table, one pair at a time. After confirming that the participant was watching the cards, the authors slowly read out the explanation of the picture cards using the name of the participant for XX, as shown in Figure 4. The cards illustrating women in the same scenes were used for the female participants. If the participant correctly answered all 4 tasks, he or she was judged to have “self-evaluation.”
Figure 4.
The 4 pairs of the picture cards to evaluate the presence or absence of self-evaluation. Task 1: Mr XXX is washing his hands after use of the toilet. Mr XXX does not wash his hands after use of the toilet. Which is better? Task 2: Mr XXX is quarrelling with his friend. Mr XXX is getting on well with his friend. Which is better? Task 3: Mr XXX is wearing his clothes in public. Mr XXX has not put his clothes on and is naked before everybody. Which is better? Task 4: Mr XXX is eating while standing. Mr XXX is eating while sitting. Which is better?
According to Lewis, 27 , 28 the “self-evaluation” ability is acquired at an age of 2.5 to 3 years. Therefore, we confirmed in advance that a large majority of nursery school children aged at least 2 years 11 months could pass the task using the picture cards illustrating children in the same scenes.
Assessment of the presence or absence of self-consciousness
Lewis 27 , 28 applied red lipstick to infants’ nose tips without drawing their attention to it and examined whether the infants touched their nose tips when looking at their faces in the mirror to assess the presence or absence of “self-consciousness.” However, the lipstick task cannot be used for people with severe dementia who do not have high curiosity or interest, unlike infants, and have an attention deficit. Therefore, the participant’s full name 38 (last name and first name), which is the core of the perception of self and others, and a symbol indicating the reality of each person, another person’s name, and a meaningless sound, “ahh,” were uttered from behind of the participant, and the presence or absence of an answer or looking back was examined. If the participant answered or looked back in response only to his or her name, he or she was judged to have “self-consciousness.”
The Presence or Absence of Incontinence
The presence or absence of incontinence was based on the care records.
Analysis Methods
The 10 steps of toilet activities were divided into 3 groups, “activities before excretion” [(1) moving from the day room; (2) entering the toilet; (3) undressing; and (4) sitting on the toilet seat], “excretion”, and “activities after excretion” [(6) cleaning up; (7) standing up from the toilet seat; (8) clothing; (9) coming out of the toilet; and (10) returning to the day room], and care conditions were placed in order from the viewpoint of motivation (initiation, maintenance, and orientation of activities) and investigated based on Hull’s drive-reduction theory 13 and our self-awareness model 23–26 for each stage of self-awareness (completion of the “theory of mind” task; noncompletion of the “theory of mind” task, but completion of the “self-evaluation” task; and noncompletion of the “self-evaluation” task, but completion of the “self-consciousness” task).
All the participants who had not passed the “self-consciousness” task used diapers and were excluded from the analysis.
Results
In all, 7 participants were considered to manage the theory of mind, 9 to be at the self-evaluation stage, and 5 to be at the self-consciousness stage. The results are described subsequently for each stage of self-awareness.
Seven Participants Who Passed the “Theory of Mind” Task
In the initiation and orientation of toilet activities before excretion (Table 1), 5 of the 7 participants spontaneously initiated the activities and 2 asked caregivers for assistance.
Table 1.
The Initiation and Orientation of Toilet Activities Before Excretion.
| Theory of mind task passers, n = 7 | Self-evaluation task passers, n = 9 | Self-consciousness task passers, n = 5 | |
|---|---|---|---|
| Spontaneously initiated without the guidance of caregivers | 5 | ||
| Asked caregivers for assistance | 2 | ||
| Initiated in response to the verbal guidance of caregivers | 5 | ||
| Initiated with behavior with intentionality toward excretion | 1a | ||
| Initiated in response to the behavioral guidance of caregivers | 3 | 3 | |
| Initiated with behavior without intentionality toward excretion | 1b | ||
| A caregiver made the participant stand up in a one-sided manner while talking to the participant | 1 |
a The participant hung around the washroom after eating.
b The participant restlessly hung around without direction in the day room.
Note: Self-evaluation task passers: the participants who did not pass the “theory of mind” task but passed the “self-evaluation” task. Self-consciousness task passers: the participants who did not pass the “self-evaluation” task but passed the “self-consciousness” task.
In the orientation and maintenance of toilet activities before excretion (Table 2), 5 participants did not need the guidance of caregivers, and 2 oriented themselves toward, and maintained, the activities with the verbal guidance of caregivers.
Table 2.
The Orientation and Maintenance of Toilet Activities Before Excretion.
| Theory of mind task passers | Self-eEvaluation task passers | Self-consciousness task passers | |
|---|---|---|---|
| Spontaneously oriented themselves and maintained activity without the guidance of caregivers | 5 | ||
| Oriented themselves and maintained activity with the verbal guidance of caregivers | 2 | 3 | |
| Oriented themselves and maintained activity with the behavioral guidance of caregivers | 6 | 2 | |
| The verbal and behavioral guidance of caregivers could not orient and maintain the participants' activities, and the participants stopped moving in the middle of the activities | 3a |
a The participants sat on the floor of the toilet, lay down in the corridor and on the floor of other places, or stood still while holding the handrail in the toilet.
Note: Self-evaluation task passers: the participants who did not pass the “theory of mind” task but passed the “self-evaluation” task. Self-consciousness task passers: the participants who did not pass the “self-evaluation” task but passed the “self-consciousness” task.
Excretion (goal achievement; Table 3) was seen in all the participants some time after sitting on the toilet seat.
Table 3.
Excretion (Goal Achievement).
| Theory of mind task passers | Self-evaluation task passers | Self-consciousness task passers | |
|---|---|---|---|
| Excretion was seen some time after sitting on the toilet seat | 7 | 8 | 4 |
| The participant sat on the toilet seat but did not excrete | 1 | 1 |
Note: Self-evaluation task passers: the participants who did not pass the “theory of mind” task but passed the “self-evaluation” task. Self-consciousness task passers: the participants who did not pass the “self-evaluation” task but passed the “self-consciousness” task.
In cleaning up after excretion (Table 4), 4 participants spontaneously initiated the activity, and 3 participants who could not do this activity due to physical problems asked caregivers for assistance.
Table 4.
The Initiation and Orientation of Toilet Activities After Excretion.
| Theory of mind task passers | Self-evaluation task passers | Self-consciousness task passers | |
|---|---|---|---|
| Spontaneously initiated cleaning-up without the guidance of caregivers | 4 | ||
| Asked caregivers for assistance | 3 | ||
| Remained sitting on the toilet seat and did not initiate cleaning-up after excretion | 8 | 4 |
Note: Self-evaluation task passers: the participants who did not pass the “theory of mind” task but passed the “self-evaluation” task. Self-consciousness task passers: the participants who did not pass the “self-evaluation” task but passed the “self-consciousness” task.
The behavior of each participant in the orientation and maintenance of toilet activities after excretion (Table 5) was similar to that in the orientation and maintenance of toilet activities before excretion (Table 2).
Table 5.
The Orientation and Maintenance of Toilet Activities After Excretion.
| Theory of mind task passers | Self-evaluation task passers | Self-consciousness task passers | |
|---|---|---|---|
| Spontaneously oriented themselves and maintained activity without the guidance of caregivers | 5 | ||
| Oriented themselves and maintained activity with the verbal guidance of caregivers | 2 | 3 | |
| Oriented themselves and maintained activity with the behavioral guidance of caregivers | 6 | 2 | |
| The verbal and behavioral guidance of caregivers could not orient and maintain the participants' activities, and the participants stopped moving in the middle of the activities | 3a |
Note: Self-evaluation task passers: the participants who did not pass the ‘theory of mind’ task but passed the ‘self-evaluation’ task. Self-consciousness task passers: the participants who did not pass the ‘self-evaluation’ task but passed the ‘self-consciousness’ task.
aThe participants stood still while holding the handrail or lay down in the corridor and on the floor of other places.
All the 7 participants had urinary incontinence.
Nine Participants Who Did Not Pass the “Theory of Mind” Task But Passed the “Self-Evaluation” Task
In the initiation and orientation of toilet activities before excretion (Table 1), no participant spontaneously initiated the activities or asked caregivers for assistance. Of the 9 participants, 5 initiated the activities in response to the verbal guidance of caregivers, and 3 in response to the behavioral guidance of caregivers holding out their hands. The remaining 1 participant hung around the washroom after eating, and a caregiver became aware of such behavior and guided the participant to the toilet.
In the orientation and maintenance of toilet activities before excretion (Table 2), no participants oriented themselves toward, or maintained, the activities. In all, 3 and 6 participants oriented themselves toward, and maintained, the activities with the verbal and behavioral guidance of caregivers, respectively.
Excretion (goal achievement; Table 3) was seen in 8 of the 9 participants some time after sitting on the toilet seat.
None of the 8 participants who showed excretion (Table 4) spontaneously initiated cleaning-up or asked caregivers to do cleaning-up, and all of them remained sitting on the toilet seat after excretion.
The behavior of each participant in the orientation and maintenance of toilet activities after excretion (Table 5) was similar to that in the orientation and maintenance of toilet activities before excretion (Table 2).
One participant had urinary incontinence, and 8 had both urinary and fecal incontinence.
Five Participants Who Did Not Pass the “Self-Evaluation” Task But Passed the “Self-Consciousness” Task
In the initiation and orientation of toilet activities before excretion (Table 1), no participants initiated the activities spontaneously or with verbal guidance. Of the 5 participants, 3 initiated the activities with the behavioral guidance of caregivers holding out their hands. A caregiver made 1 participant stand up in a 1-sided manner while talking to the participant. The remaining 1 participant restlessly hung around without direction, and a caregiver became aware of such behavior and guided the participant to the toilet. In the orientation and maintenance of toilet activities before excretion (Tables 2), no participant could be guided by words. Of the 5 participants, 3 participants stopped moving in the middle of the activities and sat on the floor of the toilet, lay down in the corridor and on the floor of other places, or stood still while holding the handrail in the toilet.
Excretion was seen in 4 participants some time after sitting on the toilet seat (Table 3), but none of these 4 participants initiated cleaning up and remained sitting on the toilet seat after excretion (Table 4).
The behavior of each participant in the orientation and maintenance of toilet activities after excretion (Table 5) was similar to that in the orientation and maintenance of activities before excretion (Table 2).
All the 5 participants had both urinary and fecal incontinence.
Discussion
At which stage of self-awareness and why do a series of toilet activities, which are acquired habits, become unfeasible in dementia? The answer to this question is considered to be well represented by the results of the participants who did not pass the theory of mind task but passed the self-evaluation task. In the initiation and orientation of toilet activities before excretion (Table 1), the participants who passed the theory of mind task spontaneously initiated the activities, and if unable to perform the activities due to physical problems asked caregivers for assistance. However, none of the participants who failed to pass the theory of mind task spontaneously initiated the activities or asked caregivers for assistance. Also, in the orientation and maintenance of toilet activities before and after excretion (Tables 2 and 5), none of these participants spontaneously oriented themselves toward, or maintained, the activities. In addition, in cleaning up after excretion (Table 4), none of them spontaneously did cleaning up or asked caregivers to do so, and all of them remained sitting on the toilet seat after excretion. Namely, when the participants lost theory of mind, their individuality markedly decreased and they needed to be guided by others’ words and actions. Theory of mind is the ability to estimate the psychological states (intention, thought, belief, desire, emotion, preference, etc) that are in the background of the behavior of self and others and cannot be directly observed. 32 It is considered that the elderly patients with dementia who had lost theory of mind had less individuality due to the vague awareness of their own excretory desire and intention, and, as a result, they became to need the guidance of caregivers in each scene of the initiation, orientation, and maintenance of a series of toilet activities, which are acquired habits. The vague awareness of their own desire and intention seems to be well represented by urinary and fecal incontinence in 8 of the 9 participants and a participant’s behavior of hanging around the washroom after breakfast (Table 1). In addition, all the participants remained sitting on the toilet seat after excretion (Table 4), and this is considered to indicate that one’s intention becomes more vague and one’s individuality further decreases if incentive (excretory desire) disappears due to excretion.
When the participants became unable to self-evaluate, none of them could be verbally guided by caregivers, and 3 of the 5 participants sat on the floor of the toilet, lay down in the corridor and on the floor of other places, or stood still while holding the handrail in the toilet (Tables 2 and 5). If one becomes unable to introspect one’s present conditions and to self-evaluate, one cannot be conscious of the present time. If the present time becomes vague, it becomes difficult to stand outside the present time to look back at oneself, and one’s time sense fades. 39 As a result, future goals based on the present time cannot exist, and one’s behavior becomes just the result of increased activity and loses directivity. This seems to be well represented by the scene in which a participant restlessly hung around without direction in the day room (Table 1). In addition, if one’s time sense fades, one does not feel boredom, and the faded time sense seems to be well represented by the state of participants who remained sitting on the toilet seat after excretion (Table 4). If one’s time sense fades and one’s drive decreases, one’s activities cease. The conditions of the participants sitting on the floor of the toilet, lying down in the corridor and on the floor of other places, and standing still while holding the handrail in the toilet are considered to be the results of the faded time sense and decreased drive. These conditions are not strange from an emotional point of view. This is because if one becomes unable to self-evaluate, one loses the emotions of shame and guilt and exhibits behavior against social rules without reluctance. 23–26
The participants who passed the theory of mind task spontaneously initiated the activities and, if unable to do so, asked others for assistance, but all of them had urinary incontinence. Namely, it can be said that the participants at this stage maintain drive, habit, and incentive but have reduced individuality and are ready to be those who do not pass the theory of mind task.
Behavior was assumed to be a product of drive, habit, and incentive (behavior = drive × habit × incentive). 13 As described previously, self-awareness is considered to affect habit and be affected by incentive, and drive affects activity. Namely, if one loses theory of mind, one becomes vaguely aware of one’s desire and intention. As a result, a series of toilet activities, which are acquired habits, begin to collapse. Furthermore, if incentive disappears, one’s intention hardly arises and toilet activities further collapse. If one loses self-evaluation, one’s time sense fades, future goals based on the present time cannot exist, and one’s behavior loses directivity. As a result, toilet activities collapse, and with a decrease in drive toilet activities cease.
Limitations of the Study
This study involved 80 people residing in a facility, and of these, 21 had been diagnosed as having dementia and used the toilet for their toilet activities. Statistical tests were not performed due to the data being spread over a large number of tabular cells, with a corresponding low frequency. Therefore, the results cannot be generalized. However, our clinical experience also convinces us that a series of toilet activities, which are acquired habits, collapse with a decrease in self-awareness in a stepwise manner.
Footnotes
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding: The authors received no financial support for the research, authorship, and/or publication of this article.
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