Communicating With Unconscious Patients: An Overview : Dimensions of Critical Care Nursing

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Communicating With Unconscious Patients

An Overview

Lawrence, Madelaine M. PhD, MSN, BSN; Ramirez, Rebecca P. MD, MHCM, FACP, SFSHM; Bauer, Paul J. RN, BA

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Dimensions of Critical Care Nursing 42(1):p 3-11, 1/2 2023. | DOI: 10.1097/DCC.0000000000000561
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Since the 1990s, nursing students have been told to speak to their unconscious patients because hearing was the last sense to go.1 However, talking to an unresponsive person is not without difficulty. There are many reasons why nurses and doctors do not speak to unconscious patients.

First, many do not believe that talking to comatose patients makes any difference. Second, health professionals can feel foolish speaking to someone unresponsive.

Third, comatose patients may seem dead or close to it, so most nurses and doctors think that their time would be better spent with viable patients. Fourth, comatose patients do not express demands or concerns that must be addressed.2

Similar issues that nurses, specifically, faced communicating with unconscious patients were also identified. These included difficulty communicating with a patient who does not respond, pressures of the work environment to work with other patients, limited knowledge about unconscious patients' needs, and limited knowledge of why or how to communicate with comatose patients.3

A study of critical care nurses in 2005 found that unconscious patients received less verbal communication and interactions than verbally responsive patients.4 By 2021, the degree to which nurses communicate with patients in intensive care units (ICUs) was influenced by the degree of responsiveness of the patient. Unconscious patients, at best, received limited explanations.5


Social categorization and dehumanization are common ways to categorize people into groups that lack human presence. It is possible to objectify and dehumanize patients who do not communicate. Some studies have found that doctors and nurses objectified hospitalized patients more than the general population.6 Unconscious patients can be seen only as a body and not a human presence without communication. Objectifying can be a protective coping strategy to reduce emotional attachment.7

Researchers who interviewed patients after a coma experience did learn what these patients heard when presumed to be unaware. In interviews with 68 patients who had recovered from the posttraumatic coma, 43 patients (63%) had no recall, 8 (12%) had some later memory, and 17 (25%) were able to recall hearing what was being said.8 In interviews with 15 trauma patients, 7 (47%) patients had no memory of events, with 8 (53%) recalling events.9

From 1987 to 1994, a researcher interviewed 111 patients who had an acute unconscious experience.10-12 Their unconscious episodes resulted from the following conditions: cardiac arrests, head injuries, diabetic coma, cerebral hemorrhages, and seizures.

The research results indicated that 5 events could occur during an unconscious episode and that some individuals experience more than 1 event (see Table 1).

TABLE 1 - States of Disorders of Consciousness
• Unconsciousness (27%)—no recollection of any events during the unconscious episode.
• Inner awareness (9%)—able to talk about what is happening without connecting to the environment.
• Perceived unconsciousness (27%)—able to hear, feel touch, and be aware of being moved but unable to move or communicate.
• Distorted consciousness (14%)—be in a state of perceptual distortion, misinterpreting environmental events, and feeling held prisoner.
• Exceptional/paranormal experiences (23%)—out-of-body and near-death experiences and near-death visits. 11

Although all of the experiences described in Table 1 are significant in the care of the unconscious patient, this article is limited to discussion about communication with an unconscious patient and advancements that have been made in the last 20 years in that regard. It will include current thinking about why and how to communicate to unconscious patients, the impact of movement on awareness, and recent advances in detecting awareness of the 25% to 40% of patients who can hear and understand what is being said and done.

In addition, 105 postcourse responses by registered nurses (89%) and other health care providers (11%), licensed practical nurses, emergency medical technicians, and cardiac technicians on how they will communicate with unconscious patients after continuing education about experiences of previously unconscious patients will be included.


A literature search was conducted, including more than 150 articles and books about the experiences of unconscious patients in several electronic databases, including PubMed, CINAHL, and the British Nursing Index. The most relevant articles are described in this article. The responses during the last 8 months in 2021 to an end-of-course question about how nurses and other health professionals will change their professional practice after attending an online continuing education course about the experiences of unconscious patients were analyzed. The responses of registered nurses and other health care providers were deemed relevant to how they would communicate with patients diagnosed as comatose.


Generally, disorders of consciousness (DOCs) are described as the state of altered response to external stimuli.13 The 3 states of awareness of self and environment are (1) coma state, with an absence of response to stimuli; (2) vegetative state, with no response to stimuli but the presence of an awake-sleep cycle; and (3) minimally conscious state, with some demonstration of awareness of self and the environment.13-15

Consciousness is often discussed as having 2 components: wakefulness and awareness.16 Wakefulness is further described as a state with eyes open and some motor arousal. If diagnosed as being in a vegetative state, a patient might be able to open their eyes, move, and go through sleeping and waking cycles. However, the lack of responses to an outside stimulus made them assume they were unaware.16 After years of research, it has been established that approximately 40% of patients with DOCs show signs of awareness that can be detected clinically or through neuroimaging.17


Increased survival even in 1988 was seen as a reason to talk to patients with DOCs because of reports of improved survival of comatose patients with whom health care professionals communicated.2

In 1994, it was believed that communication with others helps maintain a healthy physical and psychological state, with the lack of connection with others being detrimental to physical and mental health. Also, communicating helps stimulate the reticular activating system, which increases awareness.18 In 2009, additional researchers described social isolation as a risk factor for cognitive decline, poorer executive functioning, and depressive cognition.19

In a study in 2015 about social isolation, the researchers found that lack of social connection heightens health risks, the equivalent of smoking 15 cigarettes a day or having alcohol use disorder. Social isolation can also increase the risk of premature mortality.20 Also, in 2015, in a study of gene expression, researchers found that the leukocytes of lonely participants showed an increase in inflammation with a decrease in gene expression involved in antiviral responses.21

In 2016, it was found that loneliness was linked to a 30% increase in stroke or heart disease risk. Loneliness can be a precursor to stress, depression, and anxiety.22


Back in 1987, there was a belief without much evidence that some unconscious patients could hear and understand their condition and can become anxious when not oriented to where they were and what was being done to and for them.23 No communication with them might send a message they are dead or near dead.2 Patients experienced considerable frustration when hearing comments about their condition being hopeless.


Although communicating with an unconscious patient is challenging, by 2014, it was believed to ethically be the right thing to do. It is the right of all patients to be informed, particularly about procedures and treatments.24

In 2021, after attending a 3–contact hour course on experiences of previously unconscious patients on the RnCeus Interactive website, registered nurses and other health care professionals, emergency medical technicians, and cardiac technicians described their ability to be mindful of the personhood of the unconscious patient, empathizing and connecting with that person. They stated that they would treat unconscious patients like other patients, being aware that they may be alert and empathizing with them in their state of unconsciousness.

Three nurses addressed the issue of how positive people and their comments may help a patient's well-being. However, comments from negative, hostile people, such as “he's going to be a vegetable” and “I don’t think he's going to make it,” may lead to patients withdrawing or hindering their recovery.


Unconscious patients who were unaware of conversations previously said they heard comments when they were moved. Here is an example of a patient being more alert when moved from a bed to a stretcher to the x-ray department.

An x-ray technician described the following event: One late Friday afternoon, they sent a patient for a series of head x-rays. The man had had a stroke and was on a stretcher entirely out. He did not move. There was no response to anything I said or did. After finishing the 11 pictures, the orderly came down to get him. I said something to him like, ‘Why do they waste time sending down these ‘zonked out’ patients?’ He just shrugged and took the patient back upstairs.

My boss called me into the conference room a week later and said a patient wanted to see me. The patient had checked to see who had taken his head x-rays and told me he heard me say he was zonked out. He had listened to every word I said.11

This technician later became in charge of a radiology department and advised all her staff to talk to unconscious patients after relating this event. Here is another example about a patient who had a cardiac arrest at home who described these moments of awareness when moved:

I remember being put in the ambulance. From there, I only remember being picked up two times. They were lifting me up in the bed. I heard nothing and don't remember anything else.12

From interviews with patients, we know that awareness increases (1) when they are going into perceived unconsciousness, (2) when they are physically moved, and (3) when they feel pain.12 There has been no follow-up research in the last 20 years on patients increasing awareness during these 3 described times.

Here is an example of what a patient might experience when going into unconsciousness.

All I could imagine was that maybe I was dead. I didn't know what it was like to be dead, but although I could hear, there was nothing more, no sensation, and I couldn't see. The only thing I recall was hearing someone say, ‘We are losing him.’ I was trying to say something like, ‘I'm okay. I’m not dead or anything.’ I tried to talk to them, but I couldn't.

It was like I had no muscular coordination. I was thinking the words but not saying them.12

Another patient said he never experienced unconsciousness during his electrophysiology study, even though the nurses described him as becoming unconscious. He felt the jolt from the cardioversion.

I remember listening to the conversation between the technicians and the doctors. I thought things were going fine. Then, the first thing I knew, there was this tremendous jolt…like what you see in the movies when they resuscitate you. I said, you are getting pretty rough now. The nurse told me I had passed out, but I would swear that I never passed out if anyone asked me.12

The nurse with this patient said he had passed out fairly quickly. His eyes got that foggy look, and he was not responding to her. She was calling his name and tapping on his forehead, and shaking him. He went out, she believed, and she cardioverted him.12 In this instance, the patient clinically appeared to be unaware, but he was in a state of perceived unconsciousness, and even when defibrillated, he was aware.

The foggy look and unresponsiveness do not always indicate complete unconsciousness. Even though in interviews, patients who experienced the perceived unconscious state described hearing and understanding what is occurring, mainly when being moved, no extensive studies have demonstrated that awareness increased during those times. We must still address the link between awareness and movement in unconscious patients.

However, after completing the continuing education course, 4 nurses indicated that they were aware of the times when some patients can have an increase in awareness, such as when the patient was moved and when going into unconsciousness.


In 1999, Elliott and Wright conducted an observational study of 16 critical care nurses to explore verbal communication with unconscious or sedated patients. The nurses' conversations with their patients fell into 7 categories: procedural/task intentions, orientational information, reassurance, apologies/recognition of discomfort, efforts to elicit a response, intentional and unintentional distraction, and social conversation with colleagues while recognizing the patient's presence.25

Leigh26 suggested that nurses talk with unconscious patients when providing personal care to assist in keeping the patient oriented to their environment and preventing withdrawal and delirium.

In 2012, Puggina et al13 suggested the following actions be carried out by the nurse when communicating with patients with a DOC: provide an introduction, call the patient by name, inform the patient about the care being provided, speak in a normal tone of voice, avoid concomitant communication with others, and support the dignity of the patient by staying focused on them.

Three communication styles have been developed over the last decades for use with unconscious patients: structured communication, compassionate care, and telling stories. Also recommended is orienting the patient to person, place, time, and activities.

In 2015, Othman and El-hady studied 60 unconscious patients, randomly assigning half to a control group, with the other 30 receiving structured communication messages (SCMs). The SCMs included 3 parts: presentation of the caregiver and orientation information, functional assessment, and stimulation. The use of SCMS led to a decrease in physiological adverse events and a statistically significant increase in the level of consciousness compared with the control group.27

Young advocates for compassionate care for the unconscious and incapacitated. Compassionate care includes empathy with patients, a strong desire to alleviate suffering, being therapeutic in communications, and individualizing nursing care.28,29

Meghani and Punjani describe this patient's experience with a particular nurse as being empathetic and supportive:

Suddenly, I heard a voice telling me what was going on. When God gave me another chance to live my life, I was so desperate to meet and listen to the voice that every day was assuring me the courage and strength to fight for my life.24

Pape30 reported that when family members told stories to unconscious patients, those patients recovered faster, with better recovery, than patients who did not hear stories. Here is one such story.

A night nurse spoke continuously to his unconscious patient about his process of buying a new car. After a week of this conversation, the man became alert and oriented. He immediately asked the night nurse what car he bought.12

None of the recent communication articles mentioned avoiding negative conversations or unfeeling interactions. Here is one patient's reaction to the way a nurse carried out harmful direct care and communication:

One nurse would come in and never talk to me. She washed and turned me like I was a log. She was cold and unfeeling.12

Here is a patient reaction to a doctor talking about her condition after she had a stroke. When asked how these comments affected her, she said they scared her and left her hopeless.

There is nothing on the left side, one doctor had said. She'll probably be a vegetable. I doubt; I can't believe this woman's going to make it, another doctor added.12

Registered nurses (89%) and other health professionals (11%) in the post–continuing education course on the experiences of previously unconscious patients described how they will now talk to their unconscious patients. Here are the common approaches: be respectful, positive, and encouraging; orient the patient to day and time and what is being done to them; use kinder and gentler words; be considerate; and provide comfort, care, and compassion.

Nurses spoke about advocating and protecting unconscious patients from negative comments or conversations. Nurses also assumed the responsibility of talking positively to their patients and educating and encouraging their staff, colleagues, family members, and visitors to speak to the unconscious patients. The nurses also took the responsibility to monitor what was being said, ensuring it was positive and the conversation was for the patient's benefit.


In the past 20 years, using technology to detect awareness has been the area where research and development have grown the most. In 2012, researchers from the Coma Science Group in Belgium concluded that neuroimaging procedures demonstrate that patients with little or no behavioral evidence of conscious awareness may retain functional cognitive capacities. These researchers believe that these studies show the possibility of frontoparietal network connectivity modulated by specific forebrain circuit mechanisms in patients who are aware but cannot interact clinically.31

The Glasgow Coma Scale (GCS) became widely used in the 1980s—the scale tests the level of consciousness dependent on eye-opening, motor function, and verbal responses. Developed in 2005, the Full Outline of Unresponsiveness (FOUR) scale measures eye response, motor response, brainstem reflexes, and respiration patterns. It is used to identify locked-in syndrome and possible vegetative states. The FOUR scale is described as an alternative to the GCS when testing patients with impaired consciousness.32 In the ICU setting, the FOUR scale is a more effective tool to assess unconscious intubated patients because it includes assessment of brainstem reflexes and respiratory patterns and not verbal responses ( (Table 2).

TABLE 2 - Comparison of the Glasgow Coma Scale (GCS) With the Full Outline of the Unresponsiveness (FOUR) Scale
Assessed Behavior CGS FOUR
Eye response X X
Motor response X X
Brainstem reflexes X
Respiration pattern X
Verbal response X

Evidence from research shows the GCS and the FOUR scale to be useful behavioral and clinical tools but insufficient to detect awareness when the patient cannot move. These researchers state that detecting awareness has been limited to the ability to carry out a recognized behavioral response such as the squeeze of the hand asked during the GCS assessment. In the past, covertly aware patients were not detected and were wrongly diagnosed as in a vegetative state.13,33

During the 1990s, researchers conducted electroencephalographic (EEG) studies and evoked potential and heart rate variability (HRV) to detect responses from unconscious patients when they were spoken to.34 More recently, researchers used functional magnetic resonance imaging (fMRI) studies to detect awareness not identified by the behavioral methods.

In 2006, researchers used fMRI detection of responses with a patient diagnosed as being in a vegetative state for 10 months. He was talked to by different people using his first name. Cortical processing was observed in a medial prefrontal cortex region when his first name was spoken. This pattern also occurred to 3 healthy volunteers. The researchers concluded that this response indicated that the patient could understand the meaning of words and probably had some comprehension.35

Using fMRI, researchers at the Brain and Mind Institute compared the brain activity of healthy volunteers with a woman diagnosed as being in a vegetative state. The subjects were asked to first imagine playing tennis. The patient and volunteers both increased activation in the premotor cortex, commonly associated with imagining movements. When told to relax, the activity in this area in the subjects lessened. The subjects were then asked to imagine moving from room to room in their homes. The fMRI in both the healthy subjects and the patient showed increased activity in the parietal cortex and part of the parahippocampal gyrus, the areas of the brain involved in spatial navigation. The patterns of the patient and healthy volunteers were identical, leading to the conclusion the patient was conscious and aware.36

Others explored the possible consciousness of patients diagnosed as being in a vegetative state. In 2007, fMRI studies were conducted with 7 patients diagnosed as being in a vegetative state and 4 interpreted as minimally conscious.37 The subjects were spoken to using their first names. Two patients were diagnosed as vegetative, and all 4 minimally conscious patients showed activation in the auditory cortex and temporal areas.37

In 2009, 41 patients with DOCs had their responses to specific sentences that required differing degrees of language comprehension studied.38 The researchers found that 19, almost 50% of the subjects, had normal or near-normal temporal lobe responses. In addition, 4 patients had normal fMRI activity when given the most challenging talk to comprehend.38

In 2010, researchers from Cambridge, UK, and Liege, Belgium, studied 54 patients diagnosed with DOCs and 16 healthy control subjects. While using fMRI, the patients were asked to mentally carry out 2 tasks: (1) imagine standing still on a tennis court and swinging an arm to “hit the ball” back and forth to an imagined instructor and (2) imagine navigating the streets of a familiar city or walking from room to room in their home. Five patients in the study showed some modulation of brain activity. In all 5 subjects, the motor imagery response and playing tennis showed activation in the supplementary motor area. In response to the spatial imagery of walking in a familiar city or their home, 4 patients showed activation in the parahippocampal gyrus.39


In 2016, a meta-analysis was conducted of 37 subjects diagnosed as vegetative or minimally conscious, using fMRIs and EEGs to assess awareness prevalence. At least 15% of all subjects studied showed signs of preserved consciousness.40

In 2017, researchers studied 16 patients admitted to an ICU with traumatic brain injury. These patients underwent stimulus-based fMRI tests on postinjury day 9.2 ± 5.0 and EEG testing on day 9.8 ± 4.6. The researchers concluded that fMRI studies could find evidence of conscious awareness not detected by bedside examinations, with a subgroup also demonstrating EEG changes indicating awareness. They recommend further analysis of multimodal assessment with the Coma Recovery Scale-Revised, stimulus-based fMRI, and EEG to evaluate consciousness.41


Although fMRI studies can show awareness in patients who are clinically unresponsive, these tests can lack accessibility for some patients because of their physical condition and are expensive. Issues with metal implants and patients who cannot remain still are common deterrents of using fMRI.

An EEG reading indicates the electrical activity of the underlying neurons, information about neuronal population oscillations, the information flow pathway, and neural activity networks.42 An EEG can detect event-related potentials, which are voltage fluctuations connected with visual, auditory, or other sensory stimulants. The event-related potentials can detect cognitive processes, such as perception, attention, emotion, memory, and other mental activities.43

Electroencephalography measures are less expensive and not prohibitive with metallic implants and can be used at the bedside.44 Bedside detection and monitoring of awareness seem more ideal in many ways.

Sixteen patients diagnosed as vegetative were studied along with 12 healthy controls to imagine right hand and toe movements. The EEG responses indicated that 3 patients could repeatedly and reliably create EEG responses similar to the healthy volunteers.44

As researchers continue to assess the use of EEG readings, refinement is being carried out. Specific details of EEG readings are being calculated to detect more detailed descriptions of brain activities in patients with DOCs. Some features derived from EEG signal processing methods have been proposed to describe the electrical characteristics of the brain with DOC. The computation of these features is challenging for clinicians working to comprehend the corresponding physiological meanings and then put them into clinical applications.42

In 2022, there are reports of the efficacy of using a handheld EEG device to detect delirium. That same handheld device has the potential to detect awareness.45

In 2013, Owen stated the following about technological developments in detecting awareness in comatose patients.

In recent years, rapid technological developments in neuroimaging have provided new methods for revealing thoughts, actions, and intentions based solely on the pattern of activity observed in the brain. In specialized centers, these methods are now being employed routinely to detect consciousness in behaviorally nonresponsive patients when all existing clinical techniques have failed to provide that information.16


Heart rate variability, detected by an ECG, is the beat-to-beat variance of heart rates. Heart rate variability can help detect neurocardiac functions that occur in emotional states. For example, in a negative state, such as anger, frustration, and anxiety, heart rhythms become erratic and disordered. The opposite occurs with positive emotions, where heart rates become more coherent and ordered.46

In 1997, a researcher submitted to the HeartMath organization cardiac tracings of 2 patients kept at home, diagnosed with DOCs. It was assumed that neither patient was aware at the time. The tracings were combined with documentation of how family members or health care professionals communicated or touched these patients. One patient showed no change in HRV when communicated with, bathed, or moved, whereas the other showed an increase in the coherence of her heart rate when spoken to and attended to.12

Research on the effects of the compassionate presence of sitters with people in an unconscious state was conducted by the Heart Math Freeze-Framer heart monitoring program. Four comatose hospice patients and 5 hospice volunteers participated in a study detecting HRV changes when sitters near them are in a state of compassionate presence. Each sitter had a minimum of six 20-minute contact sessions with a patient. Three patients showed an increase in coherence in 14 of 28 sittings and a decrease in patient coherence in 6 of 28 sittings. In 7 of 28 sittings, there was no significant change in coherence.47

Nurses who took the experiences of previously unconscious patient continuing education course with a postcourse Survey Monkey questionnaire were asked if they believed that continuously monitoring HRV would increase the frequency of staff communicating with an unconscious patient. Of the 49 participants who answered the question, 59% said it definitely would, 35% said it probably would, and 6% said it would not. One nurse said staff would be excited to assess HRVs during their interactions with unconscious patients, and another commented on the need for more research and education.


We know from research that some patients who meet all the clinical and behavioral criteria for being unconscious can hear and understand what is said. The GCS and the FOUR scale are helpful tools to identify levels of coma but miss detecting awareness in patients who can hear and understand but not move. The estimates are that 25% to 40% of patients diagnosed with a DOC using the GCS and the FOUR scale can hear and understand what is being said in their environment. However, that awareness is, to a large extent, still undetected.8-12

According to Steven Laureys, the director of the Coma Science Group, just because patients cannot move does not mean they are unconscious—consciousness does not reside in our muscles.31

Since the 1990s, several research studies have described the impact of social isolation, a helpful term in describing the state called perceived unconsciousness. These studies indicate that there is significant physical and psychological harm done without human contact.

Several fMRI studies and those using EEG detection and HRV assessments have demonstrated the ability to assess for awareness in patients diagnosed as unconscious.

Here is Adrian Owen's, a neuroscientist at Cambridge Brain Science, assessment of the state of the art of detecting awareness in behaviorally nonresponsive patients.

Both functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) have now been shown to be effective tools for detecting covert awareness in behaviorally nonresponsive patients when standard clinical approaches cannot provide that information. Indeed, in some patients, communication with the outside world via simple “yes” and “no” questions has been achieved, even in cases where no possibility for behavioral interaction exists.48,49

The movement toward understanding the unconscious experience also involves using devices that can be interpreted at the bedside. It is believed that seeing responses to care or conversation on electrophysiological devices can improve the amount of communication rendered to patients diagnosed with some type of DOCs. Here is the perspective of Steven Laureys, the director of Coma Science Group:

In the future, it may be possible to read brain signals using scalp electrodes and a brain-computer interface. This would make communication much quicker and less costly than with a brain scanner.38


Since the 1990s, the Internet has grown in its ability to provide online education. This has occurred along with Boards of Nursing in 38 states that require contact hours for license renewal. Courses that describe more detail about communicating with unconscious patients can promote the research available on detecting awareness and the importance of communicating. Four nurses participating in the continuing education course on the experiences of previously unconscious patients commented on the value of the information in their care of unconscious patients. Here are 2 participants' comments:

All my questions were answered thru this course regarding what is happening inside the mind of an unconscious patient.

This CE course provided essential, yet little-known, knowledge for healthcare providers. As a healthcare provider taking care of various patients, the knowledge gained will help provide better and more thoughtful care.


To our knowledge, the information presented in this article about detecting awareness in patients who cannot behaviorally respond is not presented in critical care nursing textbooks. Yet, critical care nursing textbooks are key teaching tools that educators and preceptors use. We now have strong evidence to support the importance of nurses communicating with all unconscious patients and strong evidence about how to detect this patient awareness at the bedside. Including this information in textbooks will assist preceptors and educators expand their teaching on communication with unconscious patients.


Also, there needs to be a movement to assess awareness in patients diagnosed as unconscious to be a standard of nursing care. With that comes many ethical and legal issues for which guidelines must be developed. Further research still needs to be done on the increased awareness patients have said occurred when moved.

Currently, strong documented evidence from interviews with previously unconscious patients and electrophysiological methods show awareness can be detected in patients perceived to be unconscious. It is crucial that nurses use this evidence and always communicate with unconscious patients.


The authors thank Bette Steward and Barbara Gordon for the diligent article review and the library staff and administration at the AHEC Library affiliated with Atrium Health in Charlotte, North Carolina, for their fast and always approachable assistance with needed resources.


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Awareness; Communication; EEG; fMRI; Heart rate variability; Unconscious patients

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