RESONANCES IN THE CARDIOVASCULAR SYSTEM

Investigation and Clinical Applications

Evgeny G. Vaschillo, Bronya Vaschillo, Jennifer F. Buckman, Marsha E. Bates

and Robert J. Pandina

Center of Alcohol Studies, Rutgers,The State University of New Jersey, 607 Allison Road, Piscataway, NJ 08854, U.S.A.

Keywords: Baroreflex, Closed-loop control system, Resonance frequency, HRV biofeedback.

Abstract: The baroreflex, as a control system with negative feedback, is a mechanism that buffers changes in blood

pressure (BP), thereby precluding strong, abrupt shifts in arterial pressure. As a closed-loop control system

with delays, the baroreflex possesses resonance features at frequencies of about 0.1 and 0.03 Hz. These

resonance frequencies correspond to a ~5-s delay in the BP response to changes in heart rate (HR) (HR

baroreflex closed-loop) and a ~15-s delay in the vascular tone (VT) response to changes in BP (VT

baroreflex closed-loop). Thus, whereas a single impact on the cardiovascular system (CVS) elicits a HR,

BP, and VT oscillatory response that fades over time, 0.1 or 0.03 Hz rhythmical stimulation of the CVS

produces steady HR, BP, and VT oscillations with significantly higher amplitudes comparing to stimulation

at other frequencies. Resonances in the baroreflex system are essential for the maintenance of optimal health

by keeping autonomic regulation active via HR, BP, and VT variability, providing adaptive responses to

internal and external stimuli, and buffering stress and emotional reactivity via inhibitory effect in the brain.

This study investigates the phenomenon of resonances in the CVS and the ability to employ these

resonances for clinical applications.

1 INTRODUCTION

The arterial baroreflex is a mechanism that

participates in blood pressure (BP) control. A shift in

BP triggers the baroreflex, which changes heart rate

(HR) and vascular tone (VT) to counteract the BP

shift. Most often, these HR and VT baroreflex

systems are modelled using the classic “control

system theory” approach, which conceptualizes the

baroreflex as a closed-loop control system with

negative feedback. These models are consistent with

the premise that a critical function of the baroreflex

system is to buffer BP oscillation (Just et al., 1994;

Jones, Christou, Jordan, & Seals, 2003; Jordan et al.,

2002). Control system models of the baroreflex,

however, often identify resonance properties at

certain frequencies (Magosso, Biavati, & Ursino,

2001; Julien, 2006; van de Vooren et al., 2007),

which, at first glance, seems inconsistent for a

system that is defined by its ability to buffer BP

variability. By definition, though, a closed-loop

control system with a delay possesses resonance

features and thus the classic control system theory is

consistent with both the baroreflex’s buffering

functions and its resonance properties.

The baroreflex system in humans demonstrates

resonance properties at frequencies of about 0.1 Hz

and 0.03 Hz (van de Vooren et al., 2007; Vaschillo

et al., 2002). In the HR baroreflex closed-loop, a

shift in BP causes a compensatory HR response that

is delayed for approximately 5 seconds. In the VT

baroreflex closed-loop, the compensatory response

of the vasculature is delayed for approximately 10-

15 seconds (Vaschillo et al., 2002; Magosso,

Biavati, & Ursino, 2001). These delays of 5 and 15

seconds coincide with resonance oscillations at 0.1

and 0.03 Hz because the periods of these oscillations

are equal to twice the value of the delay.

A closed-loop system always possesses

resonance properties because all biological or

technical control systems have delays associated

with inertia. When creating a stabilizing technical

system with a closed-loop, the delay is manipulated

so that the resonance frequency falls far outside of

the operating frequency range. In the case of the

baroreflex system, there are two resonance

frequencies within its very narrow (~0.01-0.5 Hz)

G. Vaschillo E., Vaschillo B., F. Buckman J., E. Bates M. and J. Pandina R. (2010).

RESONANCES IN THE CARDIOVASCULAR SYSTEM - Investigation and Clinical Applications.

In Proceedings of the Third International Conference on Bio-inspired Systems and Signal Processing, pages 21-28

DOI: 10.5220/0002691200210028

 SciTePress

operating range.

Despite the current view that the main role of the

baroreflex is to buffer BP oscillations and “that

resonance is the price to be paid for effective

buffering at other frequencies” (van de Vooren et al.,

2007), we consider resonance properties of the

baroreflex as essential elements for the regulation of

autonomic and central nervous system functions. We

posit that the resonances in the baroreflex systems

are integral for the vast autonomic variability that

underlies efficient and effective homeostatic

reflexes. This is supported by evidence that

baroreflex resonance properties can act to amplify

adaptive responses to internal and external stimuli

and buffer stress and emotional reactivity through

the initiation of a cascade of neurobiological events

that produces a generalized inhibitory effect on the

brain (Dworkin et al., 1994; Nyklicek et al., 2005;

Yasumasu et al., 2006).

This paper presents the results of our

investigations of baroreflex resonance features using

a classic engineering approach. Based on the

importance of autonomic variability as well as of the

frequency dependence of autonomic reactions to

external and internal influences, our goal is to

develop therapeutic methods based on the resonance

properties of the baroreflex.

2 0.1 HZ RESONANCE IN THE

CVS

Gatchel & Lang (1973) and Lang et al. (1993) found

that HR responses to a single stimulus tended to last

approximately 10 seconds and have a triphasic

waveform, consisting of a small initial HR

deceleration, a larger mid-interval acceleration, and

a final deceleration. Onset of any stimulus - visual

(Lang, Greenwald, & Bradley, 1993) or acoustical

(Bradley & Lang, 2000), long (few second) (Bradley

& Lang, 2000) or brief (few tens ms) (Codispoti,

Bradley, & Lang, 2001) - caused the same HR

waveform response. We suggest that the triphasic

waveform of the instantaneous HR response results

directly from the inherent resonance properties of

the HR baroreflex closed-loop. Further, we

hypothesize that this basic feature of the HR

baroreflex closed-loop can serve as the foundation

for eliciting stable resonance oscillations in HR, BP,

and VT using rhythmical 0.1 Hz stimulation.

2.1 0.1 Hz Resonance in the CVS

Caused by Respiration

Respiratory activity continually perturbs the

cardiovascular system. It is well known that

breathing modulates HR with respiratory

periodicities, a phenomenon known as respiratory

sinus arrhythmia. Clynes (1960) showed that a

single inhalation or exhalation elicits nearly identical

triphasic HR waveform responses. In addition, he

reported that 0.1 Hz breathing caused high

amplitude oscillations in HR. Angelone &

Coulter

(1964) then calculated amplitude and phase transfer

functions with respiration as the input and HR as the

output for one subject who performed paced

breathing exercises at different frequencies (0.01 –

0.5 Hz range). They found that the 0.1 Hz breathing

produced the highest HR oscillation and defined this

phenomenon as resonance in the CVS. These early

studies guided the development of a heart rate

variability (HRV) biofeedback procedure based on

paced resonance frequency breathing as a novel

approach for correcting abnormal autonomic

regulation (Lehrer, Vaschillo, & Vaschillo, 2000).

HRV biofeedback has significant clinical

potential because respiration is a physiological

Respiration Volume (RV)

[ml]

-450

450

Beat-to-beat heart intervals (RRI)

[ms]

700

800

900

1000

Pulse Transit Time (PTT)

Time [s]

[ms]

400 500 600 700

230

240

250

260

270

280

RV Spectrum

PSD [10

/Hz]

0.0

0.5

1.0

1.5

2.0

RRI Spectrum

•PSD [10

/Hz]

0.00

0.25

0.50

0.75

1.00

PTT Spectrum

Frequency [Hz]

PSD [ms

/Hz]

0.0

0.1

0.2 0.3

2500

5000

7500

Figure 1: 0.1 Hz paced breathing triggers resonance

oscillations in cardiovascular functions.

function that is under voluntary control and

breathing at one’s resonance frequency produces

high-amplitude oscillations in HR, which, through

the baroreflex, spreads to other functions, such as

BP and VT (Fig. 1).

Further, we recently calculated the amplitude and

phase transfer functions of the HR control system

for eight participants and observed that each

participant demonstrated a unique resonance

frequency between 0.075 – 0.107 Hz, and that the 0º

phase shift between respiration and HR curves

BIOSIGNALS 2010 - International Conference on Bio-inspired Systems and Signal Processing

occurred precisely at the resonance frequency

(Vaschillo & Vaschillo, 2009). Thus, paced

breathing represents an easily manipulated trigger

for inducing maximal oscillations in HR and other

interrelated cardiovascular functions.

In contrast to the usual respiratory rate of 12-18

breaths per minute (0.2-0.3 Hz), HRV biofeedback

teaches participants to breathe easily and naturally

(i.e., slowly but not too deeply, to support normal

minute ventilation) at a rate of ~6 times per minute.

As part of this procedure, participants are instructed

to breathe at their resonance frequency for ~ 40

minutes per day over a 10-week period.

HRV biofeedback successfully normalized

autonomic regulation, as measured by increased

baroreflex gain and peak expiratory flow (Lehrer et

al., 2003). It demonstrated efficacy in the treatment

of asthma (Lehrer et al., 2004), major depression

(Karavidas et al., 2007), fibromyalgia (Hassett et al.,

2007), neurosis (Chernigovskaya et al., 1990), and

hypertension (McCraty et al., 2003). The therapeutic

effects in these studies were achieved through

systematic, everyday use of the HRV biofeedback

procedure and the elicited high amplitude oscillation

in HR, BP, VT, and other autonomic functions

retrained and toned homeostatic reflexes. Activation

of the baroreceptors by these oscillations also

activated inhibitory processes in the brain, thereby

dampening stress. Taken together, these data suggest

that daily “exercise” of autonomic functions

associated with normalized autonomic regulation

can restore sympathetic-vagal balance (Lehrer et al.,

2004) and buffer patients from the negative

influences of stress.

2.2 0.1 Hz Resonance in the CVS

Caused by Rhythmical Muscle

Tension

The respiration is natural rhythmical stimulator of

the CVS; however, there are other effective methods

to stimulate the CVS at its resonance frequency. For

example, the CVS functions adaptively to react to

physical load. This suggests that rhythmical paced

muscle tension (muscle tense-release cycles) at a

frequency of 0.1 Hz may also trigger resonance in

the CVS.

Method: Sixteen young healthy participants (9

female, 7 male) performed four 3.5-minute tasks (30

second inter-task interval), including a paced, 6

breaths/minute (~0.1 Hz) task as well as three paced

muscle tension tasks at frequencies of 0.05, 0.1, and

0.2 Hz in random order. Participants were seated in

a comfortable armchair in front of a computer screen

with their legs extended and supported parallel to the

floor. During the paced muscle tension tasks

participant tensed their skeletal muscles when the

computer screen turned red and relaxed their

muscles when the screen color changed to green.

ECG and finger pulse were recorded during all tasks.

Beat-to-beat HR and pulse transit time (PTT) and

their Fourier spectra were calculated for each task.

PTT was considered as estimation of the vascular

tone (shorter PTT corresponds to higher VT). The

power of the spectra at tested frequencies was used

to estimate HR and VT reactions in each task.

Results: The 0.05, 0.1, and 0.2 Hz muscle tension

manipulations produced HR and VT oscillations at

corresponding frequencies in all participants;

however, only rhythmical 0.1 Hz muscle tension

caused high amplitude HR oscillations like those

observed with 0.1 Hz breathing. Averaged across all

participants, HR and VT reactions to muscle tension

at 0.1 Hz were 4-6 times higher than at 0.2 Hz or

0.05 Hz (see Fig. 2). Nonetheless, average HR

reaction to the 0.1 Hz muscle tension task was

significantly lower than to 0.1 Hz breathing. In

contrast, average VT reaction to the 0.1 Hz muscle

tension task was significantly higher than to 0.1 Hz

breathing.

50000

100000

150000

200000

250000

0.05 Hz 0.1 Hz 0.2 Hz

RRI [ms

/H]

2000

4000

6000

8000

10000

12000

0.05 Hz 0.1 Hz 0.2 Hz

PTT [ms

/Hz]

Figure 2: Heart rate (RRI) and vascular tone (PTT)

reactions to rhythmical muscle tension at 0.05, 0.1, and 0.2

Hz. Y-Axis: power of the spectra at tested frequencies.

Data are presented as the mean ± 2 standard error bars.

Discussion: Rhythmically stimulating the CVS at its

resonance frequency with muscle tension and

breathing elicited significantly higher oscillations

than at other frequencies. These oscillations were

robust in both the HR and VT spectra. The efficacy

of the muscle tension task to stimulate HR

oscillations was lower than the efficacy of the

breathing task, but higher for VT oscillations. This

may be related to the physical load of muscle

tension, which increased mean HR and consequently

depressed HRV. These findings parallel those

reported by Lehrer et al. (2009), who noted that the

amplitude of oscillations in BP and VT caused by

0.1 Hz muscle tension stimulation was relatively

higher than those in HR. This suggests that increased

BP and VT oscillatory activity acts as a

RESONANCES IN THE CARDIOVASCULAR SYSTEM - Investigation and Clinical Applications

compensatory reaction to dampened HRV.

Conclusion: Results confirmed that rhythmical 0.1

Hz muscle tension tasks can trigger resonance in the

CVS. The ability to produce high amplitude

oscillations at this resonance frequency makes the

rhythmical muscle tension techniques potentially

valuable for developing clinical applications. In fact,

France, France, & Patterson (2006) have developed

the Rhythmical Skeletal Muscle Tension (RSMT)

technique to lower risk of a vasovagal reaction

(fainting

). RMST has been successfully employed to

avert fainting episodes that often occur during blood

collection procedures and may discourage people

from donating blood. It has also been successfully

used to treat patients with blood and injury phobias.

In their study, healthy young adults performed the

RSMT task at frequency of 0.1 Hz and demonstrated

significant increases in HR, systolic and diastolic

BP, and cerebral oxygen. High amplitude 0.1 Hz

oscillation in HR, BP, and VT were also observed.

The mechanisms by which the 0.1 Hz RSMT

procedures prevent vasovagal reactions have not

been examined. It may be due to resonance in the

CVS or simply to the increased sympathetic arousal

caused by the muscle tension. We propose that the

effect is due to the high amplitude oscillations that

activate the regulatory processes that balance

autonomic functioning and modulate the inhibitory

processes in the brain that buffer the body from

stress. Accordingly, we speculate that other kinds of

0.1 Hz RSMT procedures can be exploited by

researchers and clinicians for the development of

novel approaches to correct abnormal autonomic

regulation. France’s RSMT technique was originally

intended to be a single session performed

immediately prior to an event that could induce a

negative physiological reaction. Systematic, every

day use of this technique, however, may produce a

cumulative and longer lasting effect and, in this way,

be practical in the same way as the HRV

biofeedback procedure. In fact, such procedures may

prove especially useful in the rehabilitation process

of patients following a cerebral stroke or myocardial

infarction, in treatments where physical exercises are

prescribed (Buch, Coote, & Townend, 2002), or in

sport medicine.

2.3 0.1 Hz Resonance in the CVS

Caused by Emotional Pictures Cues

The CVS actively participates in emotional

regulation, and emotions strongly affect

cardiovascular function. Picture cues that elicit

emotional reactions have been reported to produce

the common triphasic HR response. Moreover, the

magnitude of this triphasic response, particularly the

accelerative leg, appears to accurately discriminate

picture valence (Gatchel & Lang, 1973; Lang et al.,

1993). In accordance with our model, instigating

rhythmical emotional reactions at 0.1 Hz should

produce resonance oscillation in HR, and the

oscillation amplitude should discriminate the degree

of emotional arousal. To test this, emotionally

arousing picture cues were presented at frequency of

0.1 Hz to trigger CVS resonance. In addition, the

ability of the resonance amplitude to discriminate

the degree of emotional arousal caused by block of

picture cues was assessed.

Method: Seventy-six healthy participants, between

21 and 24 years old, were individually tested. Each

participant viewed six categories of picture blocks

(negative emotional, positive emotional, and neutral,

as well as alcohol, marijuana, and ecstasy) with 30

pictures in each. Pictures were presented for 5

seconds with a 5-second inter-picture interval,

resulting in a 0.1-Hz picture presentation frequency.

The interval between each picture block was 30

seconds. Pictures were presented on a 75-cm LCD

TV (View Sonic N3000W). ECG and finger pulse

were recorded during all tasks. Beat-to-beat RRI and

pulse transit time (PTT) and their Fourier spectra

were calculated for each picture cue exposure task.

Reaction of the CVS to the picture cue block was

estimated by the power of RRI and VT spectra at

frequency of 0.1 Hz (i.e., the 0.1-Hz HR index and

the 0.1-Hz VT index, respectively). To evaluate the

sensitivity of the 0.1-Hz HR index for estimating

emotion valence, common HRV indices (total HRV,

high frequency (HF) HRV, and low frequency (LF)

HRV) were also calculated.

Results: In most cases, pictures presentation at a

frequency of 0.1 Hz caused high amplitude HR and

VT oscillations at the resonance frequency of the

CVS. The resonance in VT, however, was less

prominent than in HR. Participant’s average 0.1-Hz

HR index response to neutral picture cues was

significantly less than for any other cue block.

Conversely, the average 0.1-Hz HR index response

to negative picture cues was significantly higher

than for other picture cue blocks. Averaged 0.1-Hz

HR index responses to positive, alcohol, marijuana,

and ecstasy picture cues did not differ significantly

from one another, but there were individual

differences in the response patterns of 0.1-Hz HR

indices across picture cue blocks. For example, one

participant strongly reacted to negative and alcohol

stimuli but weakly reacted to positive and marijuana

cues; another participant showed high 0.1-Hz HR

BIOSIGNALS 2010 - International Conference on Bio-inspired Systems and Signal Processing

index responses to ecstasy cues, a moderate response

to negative and positive cues, and a weak response

to all other cue blocks (see Fig. 3).

The 0.1-Hz HR index detected individuals’

reactions to the picture cue blocks differently than

other, more commonly used HRV indices (total

HRV, HF HRV, LF HRV). For example, the 0.1-Hz

HRV index more sensitively differentiated reactions

to negative versus neutral picture cue blocks than

common HRV indices. Further, there was no

significant variability in individual reactions to

different cue blocks detected with the common HRV

indices.

Figure 3: One participant’s RRI spectra for all 0.1 Hz

picture cue tasks. The power of spectra at 0.1 Hz reflects

the strength of emotions caused by picture cue blocks.

Discussion: Emotions modulated by rhythmical

picture cue exposure at frequency of 0.1 Hz imposed

high amplitude resonance oscillation on HR and

other cardiovascular functions. We hypothesize that

the amplitude of the oscillations depends on the

degree of emotional arousal elicited by the paced

visual stimulation, but were not able to directly

assess this hypothesis. Nevertheless, the fact that

some individuals reacted more strongly to emotional

picture cues whereas others reacted more strongly to

drug-related picture cues suggests that the salience

of the stimuli has a significant impact on the

amplitude of resonance oscillations.

It is unlikely that picture cues presented at the

resonance frequency caused greater emotional

arousal than picture cues presented at others

frequencies; rather, we hypothesize that the

amplified reactivity we observe is directly related to

the presentation of emotional cues at the CVS

resonance frequency.

Our approach of using the CVS’ 0.1 Hz

resonance frequency to assess degree of emotional

arousal in response to stimuli is similar to the

engineering approach of measuring weak oscillatory

signals. An engineer tunes a measurement device to

the main frequency of the weak signal. Tuning to the

resonance frequency does not change the value of

the signal, but rather enhances the sensitivity of the

measurement device.

Conclusion: The method we have developed for

estimating emotional arousal may be useful in

psychophysiological research, particularly, for the

diagnosis of psycho-emotional disorders. In

addition, the use of paced visual stimulation may

prove useful for the treatment and rehabilitation of a

variety of disorders because visual cues may cause

high-amplitude HR oscillation similar to those

caused by paced breathing or paced muscle tension.

An advantage of picture cue stimulation is that the

content of the stimuli can be easily manipulated;

thus, it is conceivable that rhythmical visual

stimulation using cues with specific cognitive

content (e.g., emotional cues to induce altered mood

states or drug-related cues to induce craving) may

open new doors to treatment applications in the

mental health and addictions field.

3 0.03 HZ RESONANCE IN THE

CVS

The VT baroreflex is one of two interconnected

branches of the baroreflex, but is much less studied

than its counterpart, the HR baroreflex. Like the HR

baroreflex, the VT baroreflex controls BP and

participates in modulating the coordinated actions of

the central and autonomic nervous systems;

however, it does so by modulating the stretch of

blood vessel walls and operates in a lower frequency

range (Aljuri, Marini, & Cohen, 2004). Based on

prior research (Vaschillo et al., 2002; Vaschillo et

al., 1983), we hypothesized that a resonance

frequency of ~0.03 Hz would be found for the VT

baroreflex.

Based on the utility of the 0.1 Hz resonance in

developing novel medical applications for treating

various physical and mental disorders, we expected

that exploration of the 0.03 Hz resonance could

prove valuable in much the same way. However,

little is known about this resonance frequency and

thus additional basic experimental investigations are

necessary prior to the assessment of its clinical

value. Accordingly, we performed two studies to

define whether external stimuli can elicit a 0.03-Hz

oscillatory HR response (the 30 second

triphasic

RESONANCES IN THE CARDIOVASCULAR SYSTEM - Investigation and Clinical Applications

waveform response) in addition to a 0.1 Hz

response. Very strong stimuli were used to

effectively induce a 30 second triphasic response.

The first study

investigated the HR response to

highly unpleasant sounds.

Method: Seventeen adult participants were exposed

to 8 synthetic sounds which were chosen as the most

unpleasant from 362 sounds created in the lab.

Participants sat in a room and listened to each sound

at 82 dB (A) or 92 dB (A) for 2 minutes (with a 30

second inter-stimulus interval) from four equidistant

speakers. ECG was collected and beat-to-beat HR

curves were calculated (see Fig. 4).

ID: Theta

82dB

ID:24

82dB

ID:26

92dB

[

]

Sound

Heart Rate

Time [s]

0 200 400 600

100

[

]

Figure 4: Heart Rate during aversive sound exposure.

Results: Onset of unpleasant sounds usually caused

a long-duration triphasic HR response, which

appeared to contain overlapping 10-second triphasic

waveforms that lasted for about 30 seconds (see Fig.

5) Sound offset occasionally caused the same

response. Two types (Tab. 1) of 30-second triphasic

responses were found: one with an initial HR

deceleration and one with an initial HR acceleration.

Heart Rat e

Ti me [ s ]

HR [bpm]

100 15 0 200 25 0

Soun d

Onset

Sound

Offset

Extremum1

(13. 5bpm)

Extremum2

(8.6bpm)

33 s

Mean HR

before sound

onset

Figure 5: An example of ~0.03 Hz oscillatory HR reaction

to aversive sound (30-s triphasic waveform HR response).

Table 1: The two types of 30-s triphasic waveform HR

responses averaged across all participants and sounds

characteristics.

R R I

Time [s]

RRI [ms]

700 80 0 90 0

70 0

80 0

90 0

1000

0.027 Hz

RRI Spectrum

Frequency [Hz]

[

]

0.0 0. 1 0.2 0. 3 0.4 0.5

0.00

0.25

0.50

0.75

1.00

Time [s]

[

]

RRI

Figure 6: An example of ~0.03 Hz oscillatory HR reaction

to aversive picture cues.

The second study investigated the HR response

to highly negative pictures.

Method: See section 2.3.

Results: We found that very negative pictures (e.g.,

plane crashes, blood, violence) sometimes caused a

strong ~0.03 Hz oscillatory HR response. This HR

response usually demonstrated a significantly higher

amplitude than the 0.1 HR response (see Fig 6).

Discussion: Strong stimuli from various modalities

elicited oscillatory HR responses at a frequency of

about 0.03 Hz, which overlapped with the 0.1 Hz

response. This effect may be the result of resonance

in the VT baroreflex closed-loop. In these studies,

we employed very strong stimuli and clearly

observed 0.03 Hz oscillatory responses. Less

aversive stimuli should also be capable of eliciting

these slower oscillations; however, these oscillations

may be masked by those associated with HRV.

Future studies are needed to assess the malleability

of the 0.03 Hz resonance and its utility in clinical

applications.

Conclusion: To be value for clinical application, it

is necessary to develop experimental methods that

HEART

RATE

RESPONSE

EXTREMUM

(M ± STD ERR)

EXTREMUM

(M ± STD ERR)

OSCILLATORY

PERIOD

(M ± STD ERR)

OSCILLATORY

FREQUENCY

(M ± STD ERR)

UNITE [ BPM ] [ BPM ] [ S ] [ HZ ]

TYPE 2

7.86±0.58

-5.03±0.79

28.62 ±1.23

0.035±0.006

TYPE 2

- 8.34±0.78

4.14±1.1

26.74 ±1.86

0.037±0.007

BIOSIGNALS 2010 - International Conference on Bio-inspired Systems and Signal Processing

can reliably and easily produce stable high

amplitude oscillation in the CVS. The use of very

strong negative stimuli, while capable of producing

such oscillations, may not prove clinically useful

because of the possibility of negative psychological

side effects. Exploration of paced breathing or

rhythmical muscle tension techniques at ~0.03 Hz

warrants further study as these procedures may also

be capable of triggering therapeutic oscillation in the

same way as 0.1 Hz stimulation triggers them.

Elements of such stimulation can be found in eastern

health procedures (e.g., Yoga, Tai Chi).

4 DISCUSSION

Two resonance frequencies, at 0.1 and 0.03 Hz, have

been identified in the CVS. These resonances are

thought to reflect two interdependent closed-loop

systems with delays, namely the HR and VT

baroreflex systems and contribute independently to

the overall resonance properties for the CVS.

Typically, the baroreflex system is touted for its

ability to buffer perturbations in BP (Just et al.,

1994; Jones, Christou, Jordan, & Seals, 2003; Jordan

et al., 2002; Magosso, Biavati, and Ursino, 2001;

van de Vooren et al., 2007); however, because it has

a very narrow operating frequency range (~0.01-0.5

Hz) with 2 resonance frequencies inside this range,

the ability of the baroreflex system to stabilize the

CVS is limited. The high frequency boundary is

defined by inertia of blood mass and slow changes in

vessel tone, while the low frequency boundary is

defined by differentiative property of the

baroreceptors (i.e., they react only to the speed of

BP changes).

The long term aim of investigating the dynamic

properties of the HR and VT baroreflexes is to

develop new therapeutic methods for treating

diseases associated with the dysregulation of the

autonomic and central nervous systems. HRV

biofeedback is capable of harnessing the resonances

within the CVS and promoting health benefits.

These therapeutic effects have been linked to the

generation of generalized high-amplitude

oscillations in autonomic functions that are elicited

by the biofeedback procedure (Chernigovskaya et

al., 1990; Lehrer et al., 2003, 2004) and act to retrain

autonomic reflexes. The systematic retraining of

autonomic reflexes normalizes and improves

autonomic regulation. Our studies show that

breathing, visual cues, and muscle tension

management of the 0.1 Hz resonance is useful for

the treatment of various unhealthy physical and

mental conditions. We believe that novel therapeutic

interventions involving the VT baroreflex and its

resonance at 0.03 Hz through passive or active tasks

may also be beneficial, but additional investigations

are needed.

5 CONCLUSIONS

Classical control system theory applied to the

investigation of physiological systems can be a

useful tool for the medical practice. An engineering

approach offers the opportunity to create simple,

clinically-useful stimulation procedures which may

be used to enhance an individual’s regulatory

capacity and thus open new doors to treatment

applications in the mental health and addictions

field.

ACKNOWLEDGEMENTS

This research was supported by grants from the

National Institute of Alcohol Abuse and Alcoholism

(R01 AA015248 and K02 AA00325) and the

National Institute of Drug Abuse (P20 DA017552).

REFERENCES

Aljuri, N., Marini, R. J. R. & Cohen, R. J., 2004, Test of

dynamic closed-loop baroreflex and autoregulatory

control of total peripheral resistance in intact and

conscious sheep, Am J Physiol Heart Circ Physiol

287: H2274-H2286.

Angelone, A. & Coulter, N. A. Jr., 1964, Respiratory sinus

arrhythmia: A frequency depended phenomenon,

Journal of Applied Physiology, 19, 479–82.

Bertram, D., Barres, C., Cuisinaud, G., & Julián, C., 1998.

The arterial baroreceptor reflex of the rat exhibits

positive feedback properties at the frequency of Mayer

waves, J Physiol 513: 251–261.

Borst, C. & Karemaker. J. M., 1983, Time delays in the

human baroreceptor reflex, J Auton Nerv Syst 9: 399–

409.

Bradley, M. M. & Lang, P. J., 2000, Affective reactions to

acoustic stimuli, Psychophysiology, 37, 204-215.

Buch, A. N., Coote, J. H., & Townend, J. N., 2002.

Mortality, cardiac vagal control and physical

training—what’s the link? Exp Physiol 87: 423–435.

Burgess, D. E., Hundley, J. C., Li, S. G., Randall, D. C., &

Brown, D. R., 1997, First-order differential-delay

equation for the baroreflex predicts the 0.4-Hz blood

pressure rhythm in rats, Am J Physiol Regul Integr

Comp Physiol 273: R1878–R1884.

RESONANCES IN THE CARDIOVASCULAR SYSTEM - Investigation and Clinical Applications

Chapuis, B., Vidal-Petio, E., Orea, V., Barres, C., &

Julien, C., 2004, Linear modelling analysis of

baroreflex control of arterial pressure variability in

rats, J Physiol 559: 639–649.

Chernigovskaya, N. V., Vaschillo, E. G., Rusanovsky, V.

V., & Kashkarova, O. E., 1990, Instrumental

autotraining of mechanisms for cardiovascular

function regulation in treatment of neurotics, The SS

Korsakov's Journal of Neuropathology and Psychiatry,

90: 24–28.

Clynes, M., 1960, Respiratory sinus arrhythmia: laws

derived from computer simulation, Journal of Applied

Physiology,15(5): 863-874.

Codispoti, M., Bradley, M. M., & Lang, P., 2001, Affective

reactions to briefly presented pictures,

Psychophysiology, 38, 474-678.

Dworkin, B. R., Elbert, T., Rau, H., Birbaumer, N., Pauli,

P., Droste, C., & Brunia, C. H., 1994, Central effects

of baroreceptor activation in humans: attenuation of

skeletal reflexes and pain perception, Proc Natl Acad

Sci U S A, 91, 6329-33.

France, C. R., France, J. L., & Patterson, S. M., 2006,

Blood pressure and cerebral oxygenation responses to

skeletal muscle tension: a comparison of two physical

maneuvers to prevent vasovagal reactions, Clinical

Physiology and Functional Imaging, 26, 21–25.

Hassett, A. L, Radvanski, D. C., Vaschillo, E., Vaschillo,

B., Sigal, L., Karavidas, M., Buyske, S., & Lehrer, P.

M., 2007, A pilot study of the efficacy of heart rate

variability biofeedback in patients with fibromyalgia

syndrome, Appl Psychophysiol Biofeedback, 32, 1-10.

Jones, P. P., Christou, D. D., Jordan, J., & Seals, D. R.,

2003, Baroreflex buffering is reduced with age in

healthy men, Circulation, 107, 1770–1774.

Jordan, J., Tank. J., Shannon, J. R., Diedrich, A., Lipp, A.,

Schroder, C., Arnold, G., Sharma, A. M., Biaggioni, I.,

Robertson, D., & Luft, F. C., 2002, Baroreflex

buffering and susceptibility to vasoactive drugs,

Circulation, 105, 1459–1464.

Julien, C., 2006, The enigma of Mayer waves: Facts and

models, Cardiovasc Res, 70, 12–21.

Just, A., Wittmann, U., Nafz, B., Wagner, C. D., Ehmke,

H., Kirchheim, H. R, & Persson, P. B., 1994, The

blood pressure buffering capacity of nitric oxide by

comparison to the baroreceptor reflex, Am J Physiol

Heart Circ Physiol 267: H521–H527.

Karavidas, M. K., Lehrer, P. M., Vaschillo, E., Vaschillo,

B., Marin, H., Buyske, S., Radvanski, D., & Hasset,

A., 2007, Preliminary results of an open label study of

heart rate variability for the treatment of major

depression, Appl Psychophysiol Biofeedback, 32, 19-

30.

Lang, P. J., Greenwald, M. K., & Bradley, M. M., 1993.

Looking at pictures: Affective, facial, visceral, and

behavioral reactions, Psychophysiology, 30, 261-273.

Lehrer, P. M., Vaschillo, E., & Vaschillo, B., 2000,

Resonant Frequency Biofeedback Training to Increase

Cardiac Variability: Rationale and Manual for

Training, Appl Psychophysiol Biofeedback, 25, 181-

192.

Lehrer, P. M., Vaschillo, E., Vaschillo, B., Lu, S. E.,

Eckberg, D. L., Edelberg, R., Shih, W. J., Lin, Y.,

Kuusela, T. A., Tahvanainen, K. U. O., & Hamer, R.,

2003, Heart rate variability biofeedback increases

baroreflex gain and peak expiratory flow,

Psychosomatic Medicine, 65, 796–805.

Lehrer, P., Vaschillo, E., Vaschillo, B., Lu, S., Scardella,

A., Siddique, M., & Habib, R.., 2004, Biofeedback

treatment for asthma, Chest, 126, 352–361.

Magosso, E., Biavati, V., & Ursino, N., 2001, Analysis of

cardiovascular instability by mathematical model of

baroreflex control, Proceedings of the 23

Annual

EMBS International Conference, October 25-28,

Istanbul, Turkey. 596-599.

McCraty, R., Atkinson, M., & Tomasino, D., 2003, Impact

of a workplace stress reduction program on blood

pressure and emotional health in hypertensive

employees, J Altern Complement Med, 9, 355–369.

Nyklicek, I., Wijnen, V., & Rau, H., 2005, Effects of

baroreceptor stimulation and opioids on the auditory

startle reflex, Psychophysiology, 42, 213-22.

van de Vooren, H., Gademan, M. G. J., Swenne, C. A.,

TenVoorde, B. J., Schalij, N. J., & Van der Wall, E.

E., 2007, Baroreflex sensitivity, blood pressure

buffering, and resonance: what are the links?

Computer simulation of healthy subjects and heart

failure patients, J Appl Physiol 102: 1348-1356.

Vaschillo, E. G., Bates, M. E., Vaschillo, B., Lehrer, P.,

Udo, T., Mun, E. Y., & Ray, S., 2008, Heart rate

variability response to alcohol, placebo, and

emotional picture cue challenges: Effects of 0.1 Hz

stimulation, Psychophysiology, 45, 847-858.

Vaschillo, E., Vaschillo, B., & Lehrer, P., 2006,

Characteristics of resonance in heart rate variability

stimulated by biofeedback, Appl Psychophysiol

Biofeedback, 31, 129-142.

Vaschillo, E., Lehrer, P., Rishe, N., & Konstantinov, M.,

2002, Heart rate variability biofeedback as a method

for assessing baroreflex function: a preliminary study

of resonance in the cardiovascular system, Appl

Psychophysiol Biofeedback, 27, 1–27.

Vashchillo, E. G., Zingerman, A. M., Konstantinov, M.

A., & Menitsky, D. N., 1983, An investigation of the

resonance characteristics of the cardiovascular

system, Human Physiology, 9, 257-265.

Vaschillo, E. G. & Vaschillo

, B., 2009, Transfer function

of the heart rate control system with respiratory input.

The classical engineering approach, BIOSIGNALS

2009, 233-238.

Ursino, M. & Magosso, E., 2003, Role of short-term

cardiovascular regulation in heart period variability:

a modelling study, Am J Physiol – Heart and

Circulatory Physiology, 284, H1479-H1493.

Yasumasu, T., Reyes del Paso, G., Takahara, K., &

Nakashima, Y., 2006, Reduced baroreflex cardiac

sensitivity predicts increased cognitive performance,

Psychophysiology 43: 41-45.

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