Sex and aggression during rhesus monkey group formation

Observational data from 16 newly formed social groups of rhesus monkeys were analyzed to identify patterns of behavior that correlated with the frequency and intensity of aggression directed toward females. The results revealed significant correlations between heterosexual behavior and female-female noncontact aggression and between female homosexual behavior and female-female contact aggression. The role of female homosexual behavior and its relationship to aggression in the formation of new groups is discussed.     

Concurrent measurement of heart rate and instrumental avoidance behavior in the Rhesus monkey

A graphical method has been developed for the concurrent recording of heart beats and lever responses during behavioral experiments. The EKG signal fed into any DC amplifier goes to a fixed level trigger circuit and relay driver with its own power supply. The signal from this drives any standard cumulative recorder. Lever response rates are recorded concurrently on an additional cumulative recorder using the same paper speed.     

Associations between heart rate,perceived heart rate,and anxiety during acute psychological stress

ABSTRACT

Background: Acute psychological stress elicits increases in heart rate (HR) and anxiety. Theories propose associations between HR, perceived HR, and anxiety during stress. However, anxiety is often measured as a unidimensional construct which limits a comprehensive understanding of these relationships.

Objectives: This research explored whether HR reactivity or perceived HR change was more closely associated with cognitive and somatic anxiety during acute psychological stress.

Design: Two laboratory-based studies were conducted.

Methods: In a single laboratory session, healthy male (N?=?71; study 1) and female (N?=?70; study 2) university students completed three laboratory psychological stress tasks (counterbalanced), each with a preceding baseline. Heart rate, perceived HR change, and cognitive and somatic anxiety intensity and interpretation of anxiety symptoms were assessed immediately following each task. Data were aggregated across tasks.

Results: Actual HR change was unrelated to anxiety intensity, but was associated with more debilitative interpretations of anxiety (study 2). Perceptions of HR change were consistently associated with greater intensity of cognitive (study 1) and somatic (study 1 and 2) anxiety.

Conclusions: Perceived HR rather than actual HR is more closely associated with anxiety intensity during psychological stress. The findings have implications for stress management and the clinical treatment of anxiety symptoms.     

Electroencephalographic and blood pressure correlates of operantly conditioned heart rate in the restrained monkey

Each of four monkeys was trained to slow its heart rate and to speed its heart rate. Mean blood pressure was positively correlated with heart rate during speeding and during slowing. These correlations increased from early training to late training for all animals during slowing; however, they did not change during speeding. High voltage in the 8–14 Hz band of the EEG was correlated negatively with heart rate; however, the correlations were insignificant or low. The correlations between EEG changes and heart rate changes increased (became more negative) during the late phase of slow training but did not change reliably during speeding training. Baseline levels in all physiological functions changed as a function of stage of training. Response patterns during escape behavior indicate dissociation of heart rate and blood pressure, whereas response patterns during avoidance behavior show correlation of heart rate and blood pressure. The findings indicate that the physiological effects of heart rate slowing and heart rate speeding are different and not merely mirror images of one another.     

Changes in heart rate during feedback control of respiration

Subjects received one of eight treatments: practice at increasing heart rate with heart-rate feedback, practice at decreasing heart rate with heart-rate feedback, practice at increasing heart rate without heart-rate feedback, practice at decreasing heart rate without heart-rate feedback, practice at increasing respiration rate with respiratory feedback, practice at decreasing respiration rate with respiratory feedback, practice at increasing respiration rate with respiratory instructions only, practice at decreasing respiration rate with respiratory instructions only. Heart rate, Respiration rate, and Respiration depth were measured. Analysis indicated that subjects who controlled respiration with respiratory feedback reliably increased and decreased heart rate; subjects who controlled respiration with respiratory instructions only reliably increased but not decreased heart rate; subjects in the respiratory-feedback conditions showed higher heart-rate increase and decrease than heart-rate increase and decrease of subjects in the other six conditions.     

Contact-free measurement of heart rate, respiration rate, and body movements during sleep

We describe a noncontact method for the ambulant measurement of basic sleep physiology parameters in humans, particularly for field studies involving sleep research and sleep disturbances. This method traces the body movements, respiration, and heart action of a person at rest or asleep on a bed, using four high-resolution force sensors installed under the bedposts. The recoil movement of the body at each heartbeat, known as the cardioballistic effect, as well as the lifting and lowering of the thorax, while breathing, causes very small shifts of the center of gravity of the bed and the subject. These shifts are reflected in the altering force distributions across the four sensors. Cardiac and respiratory parameters and the subject’s movement activity can be calculated from the sensor signals. Neither electrodes nor other kinds of transducers are in direct contact with the subject, which is the main advantage of this technique over conventional methods. Laboratory experiments were carried out to estimate validity and practicability. The method has been found to be adequate, especially for automated and unattended sleep-data collection over long periods of time.     

E-wave and heart rate responses during anticipation of nonmotor events

This study concentrated on three main questions: 1) can anticipatory late negative shift (expectancy wave, E-wave) be elicited in nonmotor S1-S2 paradigm, 2) is it sensitive to variation of emotional aspects of the task and 3) is there a connection between heart rate (HR) responses and E-wave. S1 was a letter row that was replaced tachistoscopically by another letter row (S2). The task of the subjects (n=12) was to detect if the critical aspects of S2 were similar to S1. After their delayed response they received feedback of their performance. The emotional aspects of the task were varied by presenting aversive noise bursts at the end of the feedback period either always, contingently to their performance or not at all. A negative shift was present both before S2 and aversive noise (when presented). Varying the emotional aspects of the task had an effect on the amplitude of the E-wave. There was also a connection between E-wave and heart rate responses: heart rate response seemed to be a precondition for E-wave elicitation. The results support Simons’s conclusion that nonmotor E-wave reflects specifically emotional anticipation.     

Mental load,heart rate and heart rate variability

Summary Several investigators have shown that diminished sinus arrhythmia can be seen as an indication of increased mental load. The present experiment deals with the influence of different levels of mental load, operationalized as the number of binary choices per minute, on the regularity of the heart rate. Also we investigated the influence of four different rest conditions on the regularity of the heart rate.The results show that sinus arrhythmia scores differentiate significantly between several levels of mental load, but heart frequency appeared to be an even better indicator.No significant differences were found between the four rest conditions. Stability over three subsequent measurement sessions was satisfactory, and reliability within the measurement periods was very high.

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Zusammenfassung Mehrere Forscher haben gezeigt, daß abnehmende Sinusarrhythmie betrachtet werden kann als ein Indikator zunehmender mentaler Belastung.In der vorliegenden Untersuchung handelt es sich um den Einfluß verschiedener Niveaus der mentalen Belastung, operationalisiert als die Zahl der binären Wahlen pro Minute, auf die Regelmäßigkeit der Herzfrequenz.Außerdem untersuchten wir den Einfluß vier verschiedener Ruhezustände auf die Regelmäßigkeit der Herzfrequenz.Die Ergebnisse zeigen, daß auf Grund Sinusarrhythmiedaten differenziert werden kann zwischen verschiedenen Niveaus mentaler Belastung, aber die Herzfrequenz erweist sich sogar als ein besserer Indikator.Man stellte keine signifikanten Unterschiede zwischen den vier verschiedenen Ruhezuständen fest.Die Stabilität während drei verschiedener Meßperioden war befriedigend, und die Zuverlässigkeit der Messungen (reliability) innerhalb der Meßperioden war sehr groß.

     

Biological and psychological predictors of heart rate patterns during physical activity

ObjectiveLatent class modeling (LCM) offers a promising approach for examining correlates of heart rate (HR) patterns over multiple exercise sessions. This research examined biological and psychological variables associated with different patterns of HR response to physical activity (PA).MethodsIn a three-arm randomized controlled trial (exercise video games vs. standard exercise vs. non-exercise control), HR was recorded during PA sessions over a 12-week period. LCM identified three patterns of HR during PA across 189 participants in active arms: 1) high HR across sessions with low variability within sessions, 2) linear increase in HR across sessions with low variability within sessions, and 3) high variability in HR across all sessions. Associations with biological (resting heart rate, blood pressure, BMI, age, cholesterol, triglycerides, HbA1c) and psychological (depression, motivations for PA, PA-induced feelings) predictors of latent class membership were iteratively tested.ResultsPsychological variables played as important a role in the final model as biological variables for predicting latent class membership. Few differences were found between LC1 and LC2, but LC3 differed from the other two groups in that participants were likelier to report that they feel revitalized after PA (vs. LC1 and LC2), to be less motivated for PA (vs. LC1), reported greater depression (vs. LC1 and LC2), and were younger (vs. LC1).ConclusionsThese findings demonstrate the potential of LCM to identify biological and psychological factors associated with chronotropic responses to PA, and advance understanding of the role of psychological factors in chronotropic PA outcomes.     

Self-implication and heart rate variability during simulated exposure to flight-related stimuli

In the present study, the relationship between self-implication during simulated exposure to feared stimuli and Heart Rate Variability (HRV) was explored within the framework of the dynamical systems model of emotion regulation proposed by Thayer and Lane (Thayer, J.F., and Lane, R.D. (2000). A model of neurovisceral integration in emotion regulation and dysregulation. Journal of Affective Disorders, 61, 201–216.). An analogue sample of flight phobics (n=15) and a matched non-phobic control group (n=15) were presented with flight-related pictures, flight-related sounds or flight-related pictures and sounds. Significant differences on self-implication during exposure to flight-related sounds were found between low and high HRV fearful flyers, the former being more self-implied. However, the expected HRV decreases in the phobic participants exposed to feared stimuli were not found. These results emphasize the need to distinguish between high and low HRV fearful flyers in order to make a better use of the simulated exposure treatments.     

Relationship between heart rate variability and cognitive function during threat of shock

The aim of the present study was to investigate the relationship between resting heart rate variability (HRV) and cognitive functions during threat of shock. A Continuous Performance Task and a Working Memory Task were used to measure cognitive functions. Sixty-five male participants from the Royal Norwegian Navy participated. HRV was measured during baseline, test conditions and recovery. Participants were randomly assigned into non-threat and threat groups. Based on the median split of the high frequency (HF) spectral power, groups were divided into two additional groups. Overall, the high HRV participants showed superior performance on cognitive tasks independent of non-threat or threat conditions. During threat condition the low HRV group showed improved performance. Thus, individuals with high HRV were more stress tolerant and resilient in the face of environmental changes. The results from the study might have implications with regard to performance in operational settings, but also for other fields of psychological research such as individual differences, anxiety and coping.     

Relationship between heart rate variability and cognitive function during threat of shock

Abstract

The aim of the present study was to investigate the relationship between resting heart rate variability (HRV) and cognitive functions during threat of shock. A Continuous Performance Task and a Working Memory Task were used to measure cognitive functions. Sixty-five male participants from the Royal Norwegian Navy participated. HRV was measured during baseline, test conditions and recovery. Participants were randomly assigned into non-threat and threat groups. Based on the median split of the high frequency (HF) spectral power, groups were divided into two additional groups. Overall, the high HRV participants showed superior performance on cognitive tasks independent of non-threat or threat conditions. During threat condition the low HRV group showed improved performance. Thus, individuals with high HRV were more stress tolerant and resilient in the face of environmental changes. The results from the study might have implications with regard to performance in operational settings, but also for other fields of psychological research such as individual differences, anxiety and coping.