The relationship between heart rate and blood pressure reactivity in the laboratory and in the field: evidence using continuous measures of blood pressure, heart rate and physical activity

The relationship between cardiovascular reactivity in the laboratory and in everyday life has been under discussion for many years. Manuck and Krantz (1984) and light (1987) proposed three models of how laboratory reactivity could relate to real life reactions (recurrent activation, prevailing state and combined model). The aim of the present study was to test the relationship of cardiovascular reactivity in the laboratory and in the field using continuous measures of blood pressure and heart rate as well as physical activity and posture. Seventeen high and low laboratory rate pressure product (RPP) reactors were selected from a sample of 50. Continuous Finger blood pressure and heart rate (HR) were measured noninvasively with PORTAPRES for 22 hours in everyday life together with continuous measures of thigh EMG, arm movement and posture. Adrenaline, noradrenaline, cortisol, and dopamine urinary excretion Fates were determined for the same period. As predicted, high laboratory reactors showed higher daytime variability of their RPP after eliminating the effects of serial dependency and they also showed larger responses to stressful situations in everyday life. Similar, but less pronounced effects were seen for HR. High reactors also had higher daytime diastolic blood pressure (DBP) levels. In systolic blood pressure no group differences were seen. High reactors also showed higher urinary adrenaline and noradrenaline excretion rates during the day. In this study, different cardiovascular variables follow different models for the relationship between laboratory and field reactivity. For RPP and HR the &quot;recurrent activation model&quot; is supported. DBP may follow the &quot;prevailing state model.&quot; Endocrine sympathetic mechanisms appear to be involved in individual cardiovascular reactivity differences.</p

The relationship between heart rate and blood pressure reactivity in the laboratory and in the field: evidence using continuous measures of blood pressure, heart rate and physical activity

The relationship between cardiovascular reactivity in the laboratory and in everyday life has been under discussion for many years. Manuck and Krantz (1984) and light (1987) proposed three models of how laboratory reactivity could relate to real life reactions (recurrent activation, prevailing state and combined model). The aim of the present study was to test the relationship of cardiovascular reactivity in the laboratory and in the field using continuous measures of blood pressure and heart rate as well as physical activity and posture. Seventeen high and low laboratory rate pressure product (RPP) reactors were selected from a sample of 50. Continuous Finger blood pressure and heart rate (HR) were measured noninvasively with PORTAPRES for 22 hours in everyday life together with continuous measures of thigh EMG, arm movement and posture. Adrenaline, noradrenaline, cortisol, and dopamine urinary excretion Fates were determined for the same period. As predicted, high laboratory reactors showed higher daytime variability of their RPP after eliminating the effects of serial dependency and they also showed larger responses to stressful situations in everyday life. Similar, but less pronounced effects were seen for HR. High reactors also had higher daytime diastolic blood pressure (DBP) levels. In systolic blood pressure no group differences were seen. High reactors also showed higher urinary adrenaline and noradrenaline excretion rates during the day. In this study, different cardiovascular variables follow different models for the relationship between laboratory and field reactivity. For RPP and HR the &quot;recurrent activation model&quot; is supported. DBP may follow the &quot;prevailing state model.&quot; Endocrine sympathetic mechanisms appear to be involved in individual cardiovascular reactivity differences.</p

Very early hallucinatory experiences: a school-based study

BACKGROUND: The prevalence and clinical significance of hallucinatory experiences among children below 7 years of age remain unknown. We aimed to determine the independent influences of sensory deficits, the presence of an imaginary companion and metacognition on hallucinatory experiences. We assumed that hallucinatory experiences were associated with (a) sensory deficits, (b) the presence of an imaginary companion (IC) and (c) metacognition defaults (i.e. first- and second-order theory of mind default). METHODS: All children in the third year of preschool from a region of Northern France underwent medical screening. We compared the prevalence rates of visual, auditory and audio-visual hallucinatory experiences based on (a) the presence of visual or auditory deficits, (b) the actual presence of an IC and (c) metacognition. The analyses were adjusted for age. RESULTS: A total of 1,087 children aged between 5 and 7 years were included. The prevalence rates of auditory, visual and audio-visual hallucinatory experiences were 15.8%, 12.5% and 5.8%, respectively. The prevalences of different types of hallucinatory experiences were not significantly different according to sensory deficit. The prevalences of all types of hallucinatory experiences were significantly higher among children with an IC and among children with metacognition defaults. CONCLUSIONS: The association between hallucinatory experiences and sensory deficits might concern only long-lasting deficits. The association with the presence of an IC confirms experimental findings of the likelihood of perceiving words among meaningless auditory stimuli. Relations between hallucinatory experiences and theory of mind need to be addressed in longitudinal studies