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Heart Rate Variability Biofeedback for Postconcussion Syndrome: Implications for Treatment

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Heart Rate Variability (HRV) Biofeedback is used to restore balance in the activity of the sympathetic and parasympathetic branches of the autonomic nervous system by increasing or reducing the activity of either. Researchers have postulated that a fundamental cause of refractory postconcussion syndrome (PCS) is physiologic dysfunction that fails to return to normal after concussion. The primary physiologic issues identified have been altered autonomic function and impaired cerebral autoregulation. Evidence has shown that aerobic exercise training increases parasympathetic activity, reduces sympathetic activation, and improves cerebral blood flow so it may, therefore, help to reduce concussion-related physiological dysfunction. The authors hypothesize that HRV biofeedback training will ameliorate PCS by improving autonomic balance as well as cerebral autoregulation, and that there will be a relationship between increased interval variability and postconcussion symptom reduction.
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Biofeedback ÓAssociation for Applied Psychophysiology & Biofeedback
Volume 41, Issue 3, pp. 136–143 www.aapb.org
DOI: 10.5298/1081-5937-41.3.02
SPECIAL ISSUESPECIAL ISSUE
A Preliminary Study: Heart Rate Variability Biofeedback
for Treatment of Postconcussion Syndrome
Leah Lagos, PsyD, BCB,
1
James Thompson, PhD, BCN,
2
and Evgeny Vaschillo, PhD
3
1
Leah Lagos LLC, New York, NY;
2
Evoke Neuroscience, New York, NY;
3
Rutgers University, Piscataway, NJ
Keywords: biofeedback, heart rate variability, concussion, mild traumatic brain injury, baroreflex gain
Heart rate variability (HRV) biofeedback (BFB) can be used
to reduce activation of the sympathetic nervous system
(SNS) and increase activation of the parasympathetic
nervous system (PNS). A growing body of research
suggests that increased arousal of the SNS contributes to
the sustained state of postconcussion syndrome (PCS). It
has also been postulated that underactivation of the PNS
may also play a role in the postinjury state of autonomic
dystonia, wherein the autonomic nervous system is in a
state of imbalance and does not return to normal. In
addition to autonomic imbalance, patients who are
generally advised not to engage in physical exertion until
asymptomatic from concussion, are known to experience
secondary symptoms of fatigue and reactive depression.
Recent research has established that such symptoms can
delay the recovery from concussion indefinitely. By
addressing both autonomic dysfunction and the secondary
symptoms of depression and anxiety, HRV BFB may be an
effective treatment for PCS by strengthening self-regula-
tory control mechanisms in the body and improving
autonomic balance. Recent studies have suggested that
HRV BFB has a positive impact in reducing stress and
anxiety among athletes, and concussed athletes with higher
perceived control over their symptoms have been shown to
have faster recoveries post-injury. The primary purpose of
the following case study was, therefore, to assess the
feasibility of implementing HRV BFB with a concussed
athlete suffering from postconcussion syndrome (PCS). The
second objective was to prospectively examine the impact
of ten weeks of HRV biofeedback on refractory postcon-
cussion symptoms. During this pilot case study, the athlete
attended 10 weekly sessions of HRV BFB, according to the
protocol set forth by Lehrer, Vaschillo, and Vaschillo
(2000). After 10 weeks of HRV biofeedback, the athlete
exhibited clinically significant improvements in total mood
disturbance, postconcussion symptoms, and headache
severity. The results suggest that HRV BFB may be a
useful adjunctive treatment for PCS, associated with
increases in HRV and enhanced cardiovagal activity. Given
these findings, a randomized controlled trial is warranted.
Introduction
The neurosurgeon Benjamin Bell wrote in 1787 that ‘‘every
affection of the head attended with stupefaction, when it
appears as the immediate consequence of external violence,
and when no mark or injury is discovered, is in general
supposed to proceed from commotion or concussion of the
brain, by which is meant such a derangement of this organ
as obstructs its natural and usual functions, without
producing such obvious effects on it as to render it capable
of having its real nature ascertained by dissection’’ (Shaw,
2002). This definition continues to be supported by today’s
research in two ways. First, it does not imply a short-term
deficit that resolves quickly. This is evidenced by the up to
10% of sports-related and 33% of non-sports-related
concussive injuries that develop into postconcussion
syndrome (PCS). PCS is defined by the World Health
Organization’s International Classification of Diseases, or
ICD-10, as three or more of the following symptoms:
headache, dizziness, fatigue, irritability, insomnia, concen-
tration difficulty, or memory difficulty to resolve within a
3–6 week period (Boake et al., 2005). Second, the definition
provided by Bell notes that the underlying pathology of the
symptoms cannot be ascertained by dissection, thus
accurately noting that concussion is a physiological injury,
not an anatomical injury, as evidenced by negative
structural imaging results (CT, MRI) in concussive injuries
(Barth, Freeman, Boshek, & Varney, 2001; Guskiewicz,
Ross, & Marshall, 2001).
For over a century, research has demonstrated that brain
injury causes cardiac dysfunction, cerebral hypo-perfusion,
and heart rate variability (HRV) abnormality (Cushing,
1901; Furgała et al., 2007; Kahraman et al., 2010).
Additionally, concussion severity relates directly to HRV
statistics supporting the complex bidirectional nature of
heart–brain interactions (Gall, Parkhouse, & Goodman,
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2004; Goldstein, Toweill, Susanna, Sonnenthal, & Kim-
berly, 1998; Grippo & Johnson, 2009; Jennings & Zanstra,
2009; King, Lichtman, Seliger, Ehert, & Steinberg, 1997).
The correlation between HRV frequency power normali-
zation and brain injury recovery suggests that autonomic
nervous system balance is a factor in both the brain insult
and a mechanism for concussion resolution (Keren et al.,
2005).
Based on the large percentage of concussive injuries that
produce PCS, the detrimental effects of PCS on physical,
social and psychological health, and the known ineffective-
ness of symptom-based treatments to resolve PCS, there is
a need to find effective interventions that treat the
underlying injury (Leddy, Sandhu, Baker, Sodhi, & Willer,
2012). Given the understanding that concussion is a
physiological injury, it is not surprising that recent research
and clinical work that apply physiological treatment
modalities, such as subsymptom exercise training are being
shown to be successful in resolving not only the symptoms
involved with PCS but also many of the underlying
physiological disequilibria present in concussive injuries
(Leddy, Kozlowski, Fung, Pendergast, & Willer, 2007).
The primary goals for this study, therefore, were to
establish the safety and potential effectiveness of HRV
biofeedback (BFB) for treatment of PCS. Specifically, this
study addressed two main research areas. First, it examined
the impact of HRV BFB on mood, headaches, and severity
of postconcussion symptoms. Second, the impact of HRV
BFB on physiological performance as defined by low
frequency (LF) HRV, total HRV, and respiration rate was
measured. Consistent with previous literature, it was
hypothesized that HRV biofeedback would reduce PCS by
restoring autonomic balance and cerebral autoregulation
and that there would be a relationship between baroreflex
gain and symptom reduction.
Background of Patient
The patient in this applied case study was a 42-year-old
competitive athlete who suffered her first concussion
during practice. The diagnosis of postconcussion syndrome
was determined by her primary care physician after clinical
examination and was confirmed by an ImPACT test
(immediate postconcussion assessment and cognitive test-
ing), which assessed the severity of her postconcussion
symptoms. Upon obtaining an initial score of 63 indicating
high severity of postconcussion symptoms, the patient was
prescribed bed rest and 10 mg of Zoloft. At a follow-up
visit, three and a half months following the initial injury,
the patient reported an increase of postconcussion symp-
toms and scored an ImPACT score of 65. Given the lack of
evidence-based interventions to address PCS, the physician
referred the patient for heart rate variability (HRV)
biofeedback training to address physiological dysfunction.
At the onset of HRV biofeedback, the patient reported
experiencing 14 out of 16 postconcussion symptoms set
forth by the World Health Organization (Boake et al.,
2005). The patient continued her regimen of bed rest and 10
mg of Zoloft while participating in the biofeedback training.
Method
The 10-week HRV BFB protocol designed by Lehrer,
Vaschillo, and Vaschillo (2000) was implemented with the
patient. Each session lasted 45 to 60 minutes and included
four activities (A: baseline, B and C: biofeedback training,
and D: baseline) for five minutes each. Sessions 1, 4, 7, and
10 served as recording sessions. ECG and respiration were
recorded during all four tasks. In addition, measures of
headache severity, daily life functioning, and mood were
obtained during each recording session. At the initial
session, the patient’s resonance frequency was identified as
0.1 Hz, or six breaths per minute. The resonance frequency
is the rate of breathing (and frequency of heart rate
oscillation), at which the individual produces the greatest
heart rate variability. Sessions 2, 3, 5, 6, 8, and 9 were
conducted as training sessions without physiological
measures. During training sessions, the patient was taught
to breathe slowly but not too deeply at her resonance
frequency using abdominal and pursed lip breathing
techniques. For homework, the patient was asked to engage
in two 20-minute breathing practices each day for ten
consecutive weeks. The patient submitted a weekly log of
her breathing practice times to the experimenter. All data
collection was conducted at approximately the same time of
day at the experimenter’s therapy office in Manhattan.
Psychometric Measures
The patient completed questionnaires that assessed the
severity of postconcussion symptoms, impact of headaches
on daily functioning, and mood following the injury.
Rivermead Postconcussion Questionnaire (RPQ). The RPQ
is a 16-item measure of PCS severity. The test asks the
patient to rate the severity of 16 of the most common
published PCS symptoms. In each case, the symptom is
compared with how severe it was before the injury
occurred. Questions examine the cognitive, somatic, and
emotional symptoms concussed patients may experience
following their injury. Responses range from 0 (not
experienced at all) to 4 (a severe problem), and the
maximum score that can be achieved is 64.
Lagos et al.
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Headache Impact Test (HIT-6). The HIT-6 is a scientifically
validated short form questionnaire to assess headache
impact (range: 36–78). Six questions cover pain severity,
loss of work and recreational activities, tiredness, mood
alterations, and cognition. A HIT-6 score of less than 48 is
interpreted as consistent with little impact; 50–54 shows
some impact, 56–58 shows substantial impact, and .60
shows severe impact.
The Profile of Mood States–Short Form (POMS-SF). The
37-item POMS-SF consists of six affective subscales
including tension, depression, anger, vigor, fatigue, and
confusion. Responses range from 0 (not at all) to 4
(extremely). Scores are interpreted as ranging from a low
score indicative of well-being to a higher score associated
with distress. Total mood disturbance was calculated by
subtracting positive mood scores (vigor and self-esteem)
from the sum of negative mood scores (Grove &
Prapavessis, 1992).
Physiological Measures
A ProComp Infinitie(Thought Technology, Montreal,
Canada) system was used to collect cardiovascular data as
well as to provide biofeedback training. A blood volume
pulse sensor measured cardiovascular activity, including
HR and HRV. To record respiration, a respiration strain
gauge was placed around the abdomen. As the gauge
stretched, the voltage across the tube increased, and relative
changes in length were measured with a range of 1–100
units of relative strength.
Data Analysis
Beat-to-beat RR intervals (RRI) and HR were assessed from
the BVP signal. Thought Technology software (Montreal,
Canada) calculated both the frequency domain measures
from both signals. For each dependent variable, data were
graphed and visually analyzed to evaluate the effects of the
intervention (Barlow & Hersen, 1984). These graphs were
interpreted with respect to immediacy and level of change
pre- and postintervention, amount of overlapping data
points across phases, and changes in slope and/or variability
across sessions (Hrycaiko & Martin, 1996; Thelwell,
Greenlees, & Weston, 2006).
Results
Mood
As indicated in Figure 1, the athlete showed a clinically
significant decrease in total mood disturbance from 72 to 24
between sessions 1 and 10, respectively. Notably, the
athlete showed improvements in five out of five negative
mood states between session one and session ten on the
POMS-SF (Figure 2). The most dramatic change in mood
symptoms related to depression. In session 1, the patient
scored 25, which is in the severe range for depression.
Following 10 weeks of HRV biofeedback, the patient
reported a score of 2, which is associated with mild
depression. In addition, there was also an increase in vigor,
from a score of 5 (low severity) to 13 (moderate severity).
Figure 1. Profile of Mood States (POMS), short form.
HRV Biofeedback for Postconcussion Syndrome
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Headaches
The impact of headaches on daily functioning decreased
from a score of 67 to 48 after HRV biofeedback (Figure 3).
A score of 67 in the initial session indicated that the athlete
had been experiencing headaches that severely impacted her
daily life and disabled her from enjoying family, work, and
social activities. After the tenth week of HRV BFB training,
the athlete scored a 48, which indicated that her headaches
had little to no impact on her ability to function in daily life.
A score of 67 in the initial session indicated that the athlete
had more severe headaches after three months following
injury than the average concussed athletes experiences
three days after the concussion (M¼45.4, SD ¼7.0;
McLeod, Bay, Valier, Lam, & Parsons, 2013).
Figure 2. Profile of Mood States (POMS), short form.
Figure 3. Headache (HIT-6) questionnaire.
Lagos et al.
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Postconcussion Symptoms
The prevalence of postconcussion symptoms, as measured
by the RPCQ, was reduced from 57 to 15 after HRV
biofeedback (Figure 4). The initial score of 57, prior to
biofeedback training, reflected that the athlete experienced
severe postconcussion symptoms. A score of 15 in the tenth
session demonstrated that the athlete possessed minimal to
mild postconcussion symptoms. In addition, a score of 57 at
the initial session denoted that the athlete had more severe
postconcussion symptoms than the average athlete with
PCS (M¼19.1, SD ¼11.9; Ingerbrigsten, Waterloo,
Marup-Jensen, Attner, & Romner, 1998).
Physiological Performance
The data demonstrate that following 10 weeks of biofeed-
back treatment there is an increase in the patient’s total
HRV assessed using HR STD DEV in task A (Figure 5), and
patient’s baroreflex sensitivity assessed using LF HRV in
tasks A and C (Figure 6, Figure 7). The amplitude of
oscillation in response to ~0.1 Hz breathing strongly
correlates with baroreflex sensitivity.
Discussion
Training in HRV biofeedback was followed by: (a) large
short term and longer term effects on indices of autonomic
control, (b) decreases in mood disturbances and other
negative emotional states, and (c) improvements in
headaches. The authors of this study believe that the
HRV biofeedback provided three therapeutic aspects. First,
HRV biofeedback elicited high amplitude oscillations in
cardiovascular functions and thereby activated and im-
proved the performance of autonomic reflexes. This finding
is consistent with previous studies in which HRV
biofeedback training has been shown to increase baroreflex
sensitivity (Lehrer et al., 2003). Second, the resonance
frequency breathing increased LF HRV significantly,
suggesting that sympathetic–vagal balance in the autonom-
ic nervous system was restored. Lastly, high amplitude
oscillation in heart rate, caused by resonance in the
baroreflex closed loops, modulates the brain through
afferent firing from baroreceptors, and restores the balance
between inhibition and excitation processes in the brain.
Limitations and Future Directions
As this was a preliminary and clinical case study, our results
do not lead to a definitive conclusion. The absence of a
control group allows the possibility that the patient’s
improvement was due to placebo effect or nonspecific
factors rather than the intervention, or that the results will
not be replicated in all cases. We believe that spontaneous
recovery, however, is unlikely during the 10 weeks of HRV
biofeedback, since the patient was symptomatic for many
months prior to the HRV biofeedback program and did not
improve after 1 to 3 months of standard treatment.
Furthermore, the patient’s physiological and emotional
Figure 4. Rivermead Postconcussion Symptom Questionnaire (RPCSQ).
HRV Biofeedback for Postconcussion Syndrome
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Figure 6. Low frequency heart rate variability (LFHRV).
Figure 5. Heart rate standard deviation (HR STD DEV).
Lagos et al.
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symptoms improved concomitantly after the HRV biofeed-
back.
An additional limitation of this study is that the
mechanisms by which neurocognitive symptoms of PCS
were impacted by HRV biofeedback were not adequately
investigated in this study. Assessing the impact of HRV
biofeedback on attention and cognitive processing speed
could reveal much about the role of the vagus nerve and
baroreflex gain in mediating cerebrovascular changes.
Thayer and Brosschot (2005) have noted that the autonomic
nervous system includes the afferent interoceptive arm and
the efferent visceral motor arms of the sympathetic and
parasympathetic nervous system as well as higher level
integrative and regulatory neural networks found at
various levels in the brain. It is possible that the
disequilibrium in these integrative and regulatory neural
networks maybe related to the source of autonomic
dystonia that characterizes PCS. There is a growing
consensus that one fundamental cause of refractory PCS
is physiological dysfunction that fails to return to normal
after concussion (Leddy, Kozlowski, Fung, Pendergast, &
Willer, 2007). The frequent comorbidity of PCS and major
depression disorder (Belanger & Vanderplog, 2005) and
evidence of shared exacerbated activity of excitation and
depressed inhibition processes in the brain (Leddy et al.,
2007) further highlights a potential dysfunction of these
neural circuits. Indeed, one of the patient’s most dramatic
changes in PCS symptoms was the significant improvement
in depression symptoms. This supports the hypothesis that
the effects of HRV biofeedback on these higher-level brain
functions may be involved in symptom relief in PCS.
Future studies may benefit from including quantitative
electroencephalogram measures to explore the role of the
vagus nerve and baroreflex sensitivity in mediating
cerebrovascular changes.
In summary, despite the limitations inherent in this
small case study, HRV biofeedback shows promise for the
adjunctive treatment of PCS. Our findings demonstrate that
compared to symptom management intervention programs
that modulate symptom severity, for example antidepres-
sant medications and sleep aids, HRV biofeedback is a safe
and effective intervention that directly addresses at least
some of the fundamental physiological dysfunction that
occurs in the concussed patient. Additional assessment of
this intervention is warranted in larger, controlled trials.
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Leah Lagos James Thompson Evgeny Vaschillo
Correspondence: Leah Lagos, 635 Madison Avenue, Fourth Floor,
New York, NY 10022, email: DrLeahLagos@gmail.com.
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... [5][6][7][8] For example, sleep disturbance could: contribute to or exacerbate comorbid conditions such as depression, fatigue and pain 1,9 ; worsen recovery because the normal restorative and recuperative functions of sleep are disrupted 3 ; interfere directly with rehabilitation 5 ; or signal ongoing disruption of neurophysiological processes. 6,10,11 It is possible that sleep disturbance before the TBI is also a contributor to poor outcome by increasing vulnerability or reducing recovery capacity. ...
... There is limited literature assessing treatment approaches in this population. 10 This study's findings suggest that some sleep therapies (e.g., bright light therapy, melatonin, both of which are targeted at circadian dysfunction) may be of limited use after mTBI. Psychological and behavioral therapies such as cognitive behavioral therapy for insomnia (CBTi), however, which is the first-line therapy recommended for insomnia, may be beneficial. ...
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Objective Research suggests that one physiological effect of concussion is a disruption in regulation of autonomic nervous system control that affects the balance between parasympathetic and sympathetic output. While changes in heart rate after concussion have been observed, the nature of the heart rate change during progressive exercise has not been well evaluated in acutely symptomatic patients. Additionally, little is known about the relationship between HR and RPE in this population. Methods We compared changes in heart rate and perceived effort during graded treadmill exertion in recently concussed patients to elucidate the effect of brain injury on cardiovascular response to exercise. Resting HR, HR on exercise initiation, and changes in HR and RPE during the Buffalo Concussion Treadmill Test (BCTT) were compared on two test visits: When patients were symptomatic (acute) and after recovery. Results were compared with the test-retest results obtained from a control group consisting of healthy, non-concussed individuals. Results Patients had a significantly lower HR at onset of exercise when acutely concussed as compared to when recovered and reported greater perceived exertion at every exercise intensity level when symptomatic, despite exercising at lower workloads, than when recovered. Sympathetic response to increased exertion was not affected by concussion - HR increased in response to exercise at a comparable rate in both tests. These differences observed in response to exercise between the first BCTT and follow-up evaluation in initially concussed patients were not present in non-concussed individuals. Conclusion Our results suggest that during the acute phase after concussion, acutely concussed patients demonstrated an impaired ability to shift from parasympathetic to sympathetic control over heart rate at the onset of exercise. Changes in the autonomic nervous system after concussion may be more complex than previously reported. Continued evaluation of autonomic regulatory effects in the acute phase after concussion is warranted.
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Background: The neuropsychological, physical, vestibular and oculomotor sequelae of sports-related concussion are extremely well documented. However, there is a paucity of interventions for these symptoms in refractory sports-related concussions. Aim: The intent of this article is to review the known and emerging neuropsychological and psychological rehabilitation interventions for reducing morbidity in refractory sports-related concussions (SRCs). Methods: The authors openly acknowledge the limited amount of empirical data available for review, as did the Zurich consensus papers, but posit a mindful and ethical approach towards rehabilitation interventions in the absence of evidence-based guidelines. Further, rehabilitation interventions proven useful with similar injuries or illnesses, particularly non-sports-related mild TBI, will be reviewed for applicability. Such interventions include Cognitive-Behavioural psychotherapy, biofeedback, cranial electrical stimulation, neurofeedback and cognitive rehabilitation. Results and conclusions: Modified approaches for rehabilitation with young children within family and school systems are provided. Recommendations for further research are offered.
... While this patient was much more severely injured than a person with a concussion, after a lengthy course of treatment he showed improvement on multiple QEEG parameters, as well as three HRV parameters, and was able to function successfully in his personal and work life. Lagos et al. (2012) provide a comprehensive rationale for HRV BFB in prolonged PCS from hyperactivation of the sympathetic nervous system and hypoactivation of the parasympathetic nervous system. In addition to changes in HRV as an outcome measure for BFB intervention, they also recommend multimodal measures, such as cardiovascular and neurovegetative functioning, and quality of life indicators. ...
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The study of heart rate variability (HRV) has emerged as an essential component of cardiovascular health, as well as a physiological mechanism by which one can increase the interactive communication between the cardiac and the neurocognitive systems (i.e., the body and the brain). It is well-established that lack of HRV implies cardiopathology, morbidity, reduced quality-of-life, and precipitous mortality. On the positive, optimal HRV has been associated with good cardiovascular health, autonomic nervous system (ANS) control, emotional regulation, and enhanced neurocognitive processing. In addition to health benefits, optimal HRV has been shown to improve neurocognitive performance by enhancing focus, visual acuity and readiness, and by promoting emotional regulation needed for peak performance. In concussed athletes and soldiers, concussions not only alter brain connectivity, but also alter cardiac functioning and impair cardiovascular performance upon exertion. Altered sympathetic and parasympathetic balance in the ANS has been postulated as a critical factor in refractory post concussive syndrome (PCS). This article will review both the pathological aspects of reduced HRV on athletic performance, as well as the cardiovascular and cerebrovascular components of concussion and PCS. Additionally, this article will review interventions with HRV biofeedback (HRV BFB) training as a promising and underutilized treatment for sports and military-related concussion. Finally, this article will review research and promising case studies pertaining to use of HRV BFB for enhancement of cognition and performance, with applicability to concussion rehabilitation.
Chapter
Traumatic brain injury (TBI) at all levels, from concussion through severe TBI, can negatively impact multiple systems in the human body. This multisystem disturbance is evidenced by the distributed nature and complex symptom patterns of TBI individuals including brain-based symptoms such as cognitive deficits and emotional lability, as well as autonomic symptoms such as headache, nausea, and dizziness. In order to properly diagnose, predict prognosis, and guide recovery, assessment following TBI must include all physiologic systems that may have disrupted function following TBI, and must include the use of appropriate tools in order to administer a comprehensive assessment. Electrophysiology is the only available tool that directly reflects real-time neurological function through the measurement of the moment-to-moment electrical discharges of firing neurons. Tools such as event-related potentials (ERPs), derived from the electroencephalogram, and heart rate variability, derived from the electrocardiogram, are reliable, valid, and clinically available tools that have decades of research and clinical support for their use in evaluating the underlying pathophysiology of TBI on nervous system function. This chapter reviews ERP and autonomic nervous system biomarkers that have demonstrated utility in assessment and recovery tracking for individuals suffering TBI.
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Methods and subjects: The aim of this article is to summarize and to present our own results obtained with the assessment and treatment of different forms of anxiety disorders in children and adolescents such as: Posttraumatic Stress Disorder (PTSD), Obsessive Compulsive Disorder (OCD), Dental anxiety, General Anxiety Disorder (GAD), and Anxious-phobic syndrome. Some results are published separately in different journals. a) Post Traumatic Stress Disorder (PTSD) in 10 young children aged 9 ± 2, 05 y. is evaluated and discussed concerning the attachment quality. b) The group with OCD comprises 20 patients, mean age 14,5 ± 2,2 years, evaluated with Eysenck Personality Questionnaire (EPQ), Child behaviour Checklist (CBCL), K-SADS (Schedule for Affective Disorders and Schizophrenia for School age children), Beck Depression Inventory (BDI), SCWT (Stroop Colour Word task), WCST (Wisconsin Card Scoring test). c) Dental stress is evaluated in a group of 50 patients; mean age for girls 11,4 ± 2,4 years; for boys 10,7 ± 2,6 years, evaluated with (General Anxiety Scale (GASC), and Eysenck Personality Questionnaire (EPQ). d) Minnesota Multiphasic Personality Inventory (MMPI) profiles obtained for General Anxiety Disorder in 20 young females and 15 males aged 25,7± 5,35 years, and a group with Panic attack syndrome N=15 aged 19,3±4,9 years are presented and discussed by comparison of the results for healthy people. e) Heart Rate Variability (HRV) was applied for assessment and treatment in 15 anxious-phobic patients, mean age 12, 5±2,25 years and results are compared with other groups of mental disorder. Results: Children with PTSD showed a high level of anxiety and stress, somatization and behavioural problems (aggression, impulsivity, non-obedience and nightmares), complemented by hypersensitive and depressed mothers and misattachment in the early period of infancy. Consequently, the explanation of the early predisposition to PTSD was related to be the non-developed Right Orbital Cortex. The later resulted from insecure attachment confirmed in all examined children. The obtained neuropsychological profile of children with OCD confirmed a clear presence of obsessions and compulsions, average intellectual capacities, but the absence of depressive symptoms. Executive functions were investigated through Event Related Potentials on Go/NoGo tasks. Results showed that no significant clinical manifestations of cognitive dysfunction among children with OCD in the early stage of the disorder are present, but it could be expected to be appearing in the later stage of the disorder if it is no treated. In a study of 50 children randomly selected, two psychometric instruments were applied for measuring general anxiety and personal characteristics. It was confirmed that there was presence of significant anxiety level (evaluated with GASC) among children undergoing dental intervention. The difference in anxiety scores between girls and boys was also confirmed (girls having higher scores for anxiety). Results obtained with EPQ showed low psychopathological traits, moderate extraversion and neuroticism, but accentuated insincerity (L scale). L scales are lower by increasing of age, but P scores rise with age, which can be related to puberty. No correlation was found between personality traits and anxiety except for neuroticism, which is positively correlated with the level of anxiety. The obtained profiles for MMPI-201 in a group of patients with general anxiety are presented as a figure. Females showed only Hy peak, but in the normal range. However, statistics confirmed significant difference between scores in anxiety group and control (t= 2, 25164; p= 0, 038749). Males showed Hs-Hy-Pt peaks with higher (pathological) scores, related to hypersensitivity of the autonomic nervous system, as well as with manifested anxiety. Calculation confirmed significant difference between control and anxiety in men (t= 15.13, p=0.000). Additionally, MMPI profiles for patients with attack panic syndrome are also presented as a figure. Control scales for females showed typical V form (scales 1 and 3) related to conversing tendencies. In addition, females showed peaks on Pt-Sc scales, but in normal ranges. Pathological profile is obtained in males, with Hy-Sc peaks; this profile corresponds to persons with regressive characteristics, emotionally instable and with accentuated social withdraw. Heart rate variability (HRV) is a measure of the beat to beat variability in heart rate, related to the work of autonomic nervous system. It may serve as a psychophysiological indicator for arousal, emotional state and stress level. We used HRV in both, the assessment and biofeedback training, in a group of anxious-phobic and obsessive-compulsive school children. Results obtained with Eysenck Personality Questionnaire showed significantly higher psychopathological traits, higher neuroticism and lower lie scores. After 15 session HRV training very satisfying results for diminishing stress and anxiety were obtained.
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