scholarly journals Luminescent Flash Avoidance in the Nocturnal Crab Portunus Xantusii: I. The Effects of Luminescence and Mechanical Stimulation on Heart Rate

1990 ◽  
Vol 148 (1) ◽  
pp. 415-426
Author(s):  
MATTHEW S. GROBER
Keyword(s):  
Heart Rate ◽  
Body Size ◽  
Mechanical Stimulation ◽  
Cardiac Activity ◽  
Sensory Stimulation ◽  
The Body ◽  
Cardiac Response ◽  
Mechanical Stimuli ◽  
Sensory Stimuli ◽  
Cardiac Responses

In crabs, the ratio of the heart rate before to that after sensory stimulation (the response ratio) provides a reliable indicator of the effects of sensory stimulation on cardiac activity. The nocturnally active crab Portunus xantusii (Stimpson) exhibits rapid decreases in heart rate in response to the luminescent flashes produced by the sea pansy Renilla kollikeri (Pfeffer) and to mechanical stimulation. Crabs move away from luminescent and mechanical stimuli and this behavior is well correlated with the cardiac responses. Therefore, cardiac response ratios can be used as a reliable bioassay to determine the components of sensory stimuli that are important in eliciting behavioral responses. The similar cardiac responses to both luminescent and mechanical stimuli suggest that a single command pathway may be responsiblefor triggering startle behavior in response to a wide variety of rapid, brief and intense sensory stimuli. Heart rate also varied depending on the body size of the crab and the ambient temperature. Small crabs had faster heart rates than larger crabs, and the relationship between heart rate and body size is described by the equation: fH=794.3x−059222, where fH is heart rate in beats per minute and x is carapace length in millimeters.Heart rate increased with increasing temperature over a range of 10–22 °C, but no further increases occurred at higher temperatures. The Q10 for the range 10–20°C was 1.8.

DEVELOPMENT OF A DEVICE FOR CONTROL OF THE STATE OF THE ORGANISM BASED ON PHOTOPLETISMOGRAPHY USING TECHNOLOGIES OF DIGITAL ADAPTIVE FILTRATION

2020 ◽  
pp. 100-107
Author(s):  
Алексей Дмитриевич Акишин ◽  
Иван Павлович Семчук ◽  
Александр Петрович Николаев
Keyword(s):  
Heart Rate ◽  
Cardiovascular System ◽  
Adaptive Filtering ◽  
Least Squares Method ◽  
Optimal Algorithm ◽  
Heart Diseases ◽  
Cardiac Activity ◽  
Motion Artifacts ◽  
The Body ◽  
Advantages And Disadvantages

Постоянно растущий интерес к разработке новых неинвазивных и безманжетных методов измерения параметров сердечной деятельности, использование которых давало бы возможность непрерывного и удаленного контроля сердечно-сосудистой системы, обуславливает актуальность данной работы. В многочисленных публикациях продолжаются обсуждения преимуществ и недостатков различных методов ранней диагностики сердечно-сосудистых заболеваний. Однако артефакты движения являются сильной помехой, мешающей точной оценке показателей функционирования сердечно-сосудистой системы. Одним из перспективных методов контроля является метод оценки физиологических параметров с использованием фотоплетизмографии. Данная статья посвящена разработке устройства для фотоплетизмографических исследований и алгоритмических методов обработки регистрируемых сигналов для обеспечения мониторинга сердечного ритма с заданной точностью. В работе используются технологии цифровой адаптивной фильтрации полученных сигналов для мониторинга сердечного ритма в условиях внешних механических и электрических помеховых воздействий, ухудшающих точностные характеристики системы, а также разработана архитектура системы и изготовлен макет устройства, который позволил провести измерения для определения оптимального алгоритма цифровой обработки сигналов. При использовании устройства применялись методы адаптивной фильтрации на основе фильтров Винера, фильтров на основе метода наименьших квадратов и Калмановской фильтрации. Разработанное устройство для фотоплетизмографических исследований обеспечило возможность мониторинга сердечного ритма с заданной точностью, контроля текущего состояния организма и может быть использовано в качестве средства диагностики заболеваний сердца The constantly growing interest in the development of new non-invasive and cuff-free methods for measuring the parameters of cardiac activity, the use of which would give the possibility of continuous and remote monitoring of the cardiovascular system, determines the relevance of this work. Numerous publications continue to discuss the advantages and disadvantages of various methods of early diagnosis of cardiovascular disease. However, motion artifacts are a strong hindrance to the accurate assessment of the performance of the cardiovascular system. One of the promising control methods is the method for assessing physiological parameters using photoplethysmography. This article is devoted to the development of a device for photoplethysmographic studies and algorithmic methods for processing recorded signals to ensure monitoring of the heart rate with a given accuracy. The work uses technologies of digital adaptive filtering of the received signals to monitor the heart rate in conditions of external mechanical and electrical interference, which worsen the accuracy characteristics of the system, as well as the architecture of the system and a prototype of the device, which made it possible to carry out measurements to determine the optimal algorithm for digital signal processing. When using the device, the methods of adaptive filtering based on Wiener filters, filters based on the least squares method and Kalman filtering were used. The developed device for photoplethysmographic studies provided the ability to monitor the heart rate with a given accuracy, control the current state of the body and can be used as a means of diagnosing heart diseases

Modulation of Neurocardiac Function by Oesophageal Stimulation in Humans

1997 ◽  
Vol 92 (2) ◽  
pp. 167-174 ◽  
Author(s):  
Gervais Tougas ◽  
Markad Kamath ◽  
Geena Watteel ◽  
Debbie Fitzpatrick ◽  
Ernest L. Fallen ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Power Spectrum ◽  
High Frequency ◽  
Low Frequency ◽  
Sensory Stimulation ◽  
Sensory Stimuli ◽  
Autonomic Reflexes ◽  
Low Frequency Power ◽  
Beat Heart

1. The heart and the oesophagus have similar sensory pathways, and sensations originating from the oesophagus are often difficult to differentiate from those of cardiac origin. We hypothesized that oesophageal sensory stimuli could alter neurocardiac function through autonomic reflexes elicited by these oesophageal stimuli. In the present study, we examined the neurocardiac response to oesophageal stimulation and the effects of electrical and mechanical oesophageal stimulation on the power spectrum of beat-to-beat heart rate variability in male volunteers. 2. In 14 healthy volunteers, beat-to-beat heart rate variability was compared at rest and during oesophageal stimulation, using either electrical (200 μs, 16 mA, 0.2 Hz) or mechanical (0.5 s, 14 ml, 0.2 Hz) stimuli. The power spectrum of beat-to-beat heart rate variability was obtained and its low- and high-frequency components were determined. 3. Distal oesophageal stimulation decreased heart rate slightly (both electrical and mechanical) (P < 0.005), and markedly altered heart rate variability (P < 0.001). Both electrical and mechanical oesophageal stimulation increased the absolute and normalized area of the high-frequency band within the power spectrum (P < 0.001), while simultaneously decreasing the low-frequency power (P < 0.005). 4. In humans, oesophageal stimulation, whether electrical or mechanical, appears to amplify respiratory-driven cardiac vagoafferent modulation while decreasing sympathetic modulation. The technique provides access to vagoafferent fibres and thus may yield useful information on the autonomic effects of visceral or oesophageal sensory stimulation.

The Role of the Aortic Body Chemoreceptors in the Cardiac and Respiratory Responses to Acute Hypoxia in the Anesthetized Dog

1973 ◽  
Vol 51 (4) ◽  
pp. 249-259 ◽  
Author(s):  
G. P. Biro ◽  
J. D. Hatcher ◽  
D. B. Jennings
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Acute Hypoxia ◽  
Control Period ◽  
Indirect Evidence ◽  
Minute Volume ◽  
Significant Rise ◽  
Cardiac Response ◽  
Cardiac Responses ◽  
Respiratory Parameters

The participation of the aortic chemoreceptors in the reflex cardiac responses to acute hypoxia is suggested only by the indirect evidence of pharmacological stimulation of these receptors. In order to assess their role more directly, the response to a 15 min period of hypoxia was determined after surgical denervation of the aortic chemoreceptors (A.D.), and compared with the response of sham-operated (S.O.) dogs, anesthetized with morphine–pentobarbital. In the control period, while breathing room air, the cardiovascular and respiratory parameters measured in the A.D. animals were not different from those of the S.O. dogs. Hypoxia (partial pressure of oxygen approximately 30 mm Hg) in the S.O. dogs was associated with a statistically significant rise in the heart rate (+71 ± 7 min−1, mean ± S.E.M.) and of the cardiac output (+25 ± 10 ml kg−1 min−1). In the A.D. animals, the significantly smaller increment in heart rate (+29 ± 6 min−1) was associated with a fall of the cardiac output (−16 ± 12 ml kg−1 min−1). The hypoxia-induced changes in heart rate and cardiac output in the S.O. animals were different (p < 0.05) from those in the A.D. group. The minute volume of ventilation was significantly augmented in both groups, and to a comparable extent. These findings indicate that the aortic chemoreceptors play a significant role in the cardiac response to hypoxia, but they do not affect, to a significant extent, the respiratory response.

Naive Ducklings Show Different Cardiac Response To Hawk Than To Goose Models

Behaviour ◽  
1980 ◽  
Vol 74 (1-2) ◽  
pp. 101-112 ◽  
Author(s):  
Patricia G. Parker ◽  
Helmut C. Mueller
Keyword(s):  
Heart Rate ◽  
Emotional Response ◽  
The Other ◽  
Cardiac Response ◽  
Specific Experience ◽  
Cardiac Responses

AbstractNaive mallard ducklings were exposed to overflights of a silhouette of either a hawk or a goose on one day and the other configuration on the next day. An audio record of the heart rate was recorded utilizing a small transducer. Most of the ducklings (14 of 20) showed a greater variance in heart rate in response to the hawk than to the goose (p<0.01 ). These results indicate that the ducklings without prior, specific experience can differentiate between a goose and a hawk and show a greater emotional response to the latter. This constitutes evidence for the recognition of configurational stimulus without prior, pertinent experience. The use of cardiac responses as a measure of emotionality or fear is discussed, as are the merits of various measures of changes in heart rate. We conclude that variance in heart rate is an excellent measure of emotional response to a stimulus.

scholarly journals The contribution of nasal receptors to the cardiac response to diving in restrained and unrestrained redhead ducks (Aythya americana)

1986 ◽  
Vol 121 (1) ◽  
pp. 227-238 ◽  
Author(s):  
R. A. Furilla ◽  
D. R. Jones
Keyword(s):  
Heart Rate ◽  
Local Anaesthesia ◽  
Cardiac Response ◽  
Dabbling Ducks ◽  
Diving Ducks ◽  
Cardiac Responses ◽  
Aythya Americana ◽  
Dabbling Duck ◽  
Redhead Ducks ◽  
A Minor

In restrained redhead ducks, forced submergence caused heart rate to fall from 100 +/− 3 beats min-1 (mean +/− S.E.M., N = 12) to a stable underwater rate of 35 +/− 4 beats min-1 (N = 12) within 5 s after submergence. Bradycardia was unaffected by breathing oxygen before a dive, but was virtually eliminated by local anaesthesia of the narial region. In contrast, in a dabbling duck (Anas platyrhynchos) bradycardia in short dives was eliminated by breathing oxygen before a dive. In unrestrained diving, on a man-made pond, heart rate in redheads diving voluntarily (y) was related to pre-dive heart rate (x) by the equation y = 76 + 0.29 +/− 0.05x +/− 17 (r2 = 0.71). Chasing, to induce submergence, had variable effects on this relationship. Local anaesthesia of the narial region inhibited voluntary diving but heart rates in chase-induced dives after nasal blockade were significantly higher, by 10–30%, than those obtained from untreated ducks in chase-induced dives. Breathing oxygen before voluntary dives had no apparent effect on heart rate after 2–5 s submergence. Voluntary head submersion by dabbling ducks caused no change in heart rate. We conclude that nasal receptors make only a minor contribution to cardiac responses in unrestrained dives, compared with forced dives, in diving ducks. Furthermore, these results show that little can be learned about cardiac responses in free diving ducks from studies of forced dives in dabblers or divers.

Evoked bradycardia as response criterion for the detection of electrical stimuli in catfish

2008 ◽  
Vol 58 (3) ◽  
pp. 287-299
Author(s):  
Robert Veeneklaas ◽  
Albert Schoenhage ◽  
Lonneke Eeuwes ◽  
Robert Peters
Keyword(s):  
Heart Rate ◽  
Response Criterion ◽  
Ultradian Rhythm ◽  
Mechanical Stimuli ◽  
Heart Rate Deceleration ◽  
Orienting Reflex ◽  
Sensory Stimuli ◽  
Ictalurus Nebulosus ◽  
Rate Deceleration ◽  
Electrical Stimuli

AbstractHeart rate deceleration (HRD) after exposure to novel stimuli is part of the orienting reflex, and can be used as a tool to investigate the susceptibility of various organisms to sensory stimuli. HRD as response criterion was used in unrestrained catfish, Ameiurus (Ictalurus) nebulosus (Lesueur, 1819) to investigate its susceptibility to electrical stimuli. HRD in catfish occurs after stimulation with light, mechanical stimuli, and electrical stimuli. HRD shows habituation and correlates with stimulus strength. The response to sinusoidal electrical stimuli from 70 to 700 μV/cm p-p was determined in the range from 0.1 to 1000 Hz. Using HRD as response criterion we found that at 85 μV/cm catfish react to stimuli from 0.1 to 3 Hz. In the absence of stimuli, the heart rate develops an ultradian rhythm with periods of 7 to 15 min. About twice a day cardiac arrest of 1 min occurs. During anaesthesia oscillations with a period of about 1 min are recorded. Comparison of this study with others supports the notion that there exist at least two neural channels for processing electrical stimuli. One channel is involved in predation, namely processing the fast potential changes accompanying the passage of a bioelectric dipole; another is involved in processing uniform DC fields used for navigation.

scholarly journals HRV ANALYSIS USING ECG AS DATA SOURCE

2013 ◽  
pp. 139-142
Author(s):  
RASHMI A. DESHPANDE
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Autonomic Function ◽  
Physical Phenomenon ◽  
Cardiac Activity ◽  
The Body ◽  
Time Interval ◽  
Ecg Signal ◽  
Data Source ◽  
Hrv Analysis

Heart Rate Variability (HRV) is a physical phenomenon where the time interval between heart beats varies. It is measured by the variation in the beat to beat interval. Abnormalities present in the time interval between R wave peaks in the Electro-cardiogram (ECG) indicate cardiac dysfunction. Autonomic Nervous System controls the cardiac activity of the body and provides the beat to beat regulation of the cardiovascular system. Thus Heart Rate Variability is an important tool to access autonomic function also. The source for HRV is a continuous beat to beat measurement of interbeat intervals. An ECG signal can be used as the data source for HRV analysis. In this study the HRV data is obtained from ECG signal and is processed to calculate spectral HRV index, LF/HF ratio.

scholarly journals A multi-point heart rate monitoring using a soft wearable system based on fiber optic technology

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniela Lo Presti ◽  
Francesca Santucci ◽  
Carlo Massaroni ◽  
Domenico Formica ◽  
Roberto Setola ◽  
...  
Keyword(s):  
Heart Rate ◽  
Continuous Monitoring ◽  
Cardiac Activity ◽  
Simultaneous Recording ◽  
The Body ◽  
Wearable System ◽  
Feasibility Assessment ◽  
Recent Developments ◽  
Sensor Configuration ◽  
Sensor Positioning

AbstractEarly diagnosis can be crucial to limit both the mortality and economic burden of cardiovascular diseases. Recent developments have focused on the continuous monitoring of cardiac activity for a prompt diagnosis. Nowadays, wearable devices are gaining broad interest for a continuous monitoring of the heart rate (HR). One of the most promising methods to estimate HR is the seismocardiography (SCG) which allows to record the thoracic vibrations with high non-invasiveness in out-of-laboratory settings. Despite significant progress on SCG, the current state-of-the-art lacks both information on standardized sensor positioning and optimization of wearables design. Here, we introduce a soft wearable system (SWS), whose novel design, based on a soft polymer matrix embedding an array of fiber Bragg gratings, provides a good adhesion to the body and enables the simultaneous recording of SCG signals from multiple measuring sites. The feasibility assessment on healthy volunteers revealed that the SWS is a suitable wearable solution for HR monitoring and its performance in HR estimation is strongly influenced by sensor positioning and improved by a multi-sensor configuration. These promising characteristics open the possibility of using the SWS in monitoring patients with cardiac pathologies in clinical (e.g., during cardiac magnetic resonance procedures) and everyday life settings.

scholarly journals THE FUNCTION OF THE BRAIN IN LOCOMOTION OF THE POLYCLAD WORM, YUNGIA AURANTIACA

1923 ◽  
Vol 6 (1) ◽  
pp. 73-76 ◽  
Author(s):  
A. R. Moore
Keyword(s):  
Mechanical Stimulation ◽  
Sensory Stimulation ◽  
The Body ◽  
Anterior Region ◽  
Spontaneous Movement ◽  
Peripheral Stimulation ◽  
Motor Nerves ◽  
Low Threshold ◽  
The Brain ◽  
Stimulation Of

Coordinated swimming movements in Yungia are not dependent upon the presence of the brain. The neuromuscular mechanism necessary for spontaneous movement and swimming is complete in the body of the animal apart from the brain. Normally this mechanism is set in motion by sensory stimulation arriving by way of the brain. The latter is a region of low threshold and acts as an amplifier by sending the impulses into a great number of channels. When the head is cut off these connections with the sensorium are broken, consequently peripheral stimulation does not have its usual effect. If, however, the motor nerves are stimulated directly as by mechanical stimulation of the median anterior region, then swimming movements result. Also if the threshold of the entire nervous mechanism is lowered by phenol or by an increase in the ion ratios See PDF for Equation and See PDF for Equation then again peripheral stimulation throws the neuromuscular mechanism into activity and swimming movements result.

Neurokinin 1 and 2 antagonists attenuate the responses and NK1 antagonists prevent the sensitization of primate spinothalamic tract neurons after intradermal capsaicin

1994 ◽  
Vol 72 (4) ◽  
pp. 1464-1475 ◽  
Author(s):  
P. M. Dougherty ◽  
J. Palecek ◽  
V. Paleckova ◽  
W. D. Willis
Keyword(s):  
Dorsal Horn ◽  
Mechanical Stimulation ◽  
Intradermal Injection ◽  
Mechanical Stimuli ◽  
Spinothalamic Tract ◽  
Sensory Stimuli ◽  
Neurokinin Receptors ◽  
Neurokinin 1 ◽  
Stimulation Of

1. Activation of neurokinin receptors contributes to the excitation of many dorsal horn neurons by cutaneous sensory stimuli, particularly noxious stimuli. In the present study we investigate the role of neurokinin receptors in the activation of primate spinothalamic tract (STT) neurons by cutaneous mechanical stimuli and by intradermal injection of capsaicin. This was done by testing the responses of these neurons to a battery of cutaneous stimuli before and during infusion by microdialysis of antagonists selective for NK1 and NK2 receptors. 2. The NK1 receptor antagonists cis-3-(2-methoxybenzyl-amino-2-benzhydrylquinuclidine (CP96345) and D-Pro9-[Spiro-y-lactam]-Leu10,Trp11)-Physalaemin(1-11) (GR82334) did not significantly reduce the responses of STT cells to mechanical stimulation of the skin. Both NK1 antagonists did, however, produce a significant reduction in the responses of STT neurons to an intradermal injection of capsaicin. Finally, despite having no effects on responses to mechanical stimuli, both NK1 antagonists prevented the sensitization of the responses to cutaneous stimuli that is usually observed after intradermal injections of capsaicin. 3. The NK2 selective antagonists PhCO-Ala-Ala-D-Trp-Phe-D-Pro-Pro-Nle-NH2 (GR98400) and [Tyr5,D-Trp6,8,9,Lys10]-NKA (4–10) (MEN10376) had effects very similar to those of the NK1 antagonists, but with an important difference. Neither NK2 antagonist affected the responses of STT neurons to noxious or innocuous mechanical stimulation of the skin, but they did reduce the responses to intradermal capsaicin injections. These compounds failed to prevent capsaicin-induced sensitization. In fact, cells exposed to GR98400 or MEN10376 showed unusually sustained increases in the responses to mechanical stimuli after the first capsaicin injection, suggesting that these compounds actually induced sensitization. 4. These results support the contention that both neurokinin receptors participate in the processing of nociceptive information in the dorsal horn, especially responses to strong stimuli such as intradermal injection of capsaicin. NK1 receptors are also involved in the sensitization of STT neurons after peripheral injury. A clearer understanding of the role of NK2 receptors in sensitization requires further studies with improved antagonists.

Sign in / Sign up

Export Citation Format

Share Document