COGNITIVE CARDIOVASCULAR EXPERIMENT-1 (CARDIOCOG-1)
Research Area: Cardiovascular and Respiratory Systems
Expedition(s): 5, 7-10
Principal Investigator(s): ● Andre Aubert, Katholieke Universiteit, Leuven, Belgium
RESEARCH OBJECTIVES
The Cognitive Cardiovascular Experiment -1 (Cardiocog-1) experiment studies the impacts of
weightlessness on the cardiovascular system and the respiratory system. This investigation
examines stress, and cognitive and physiological reactions of crew members during short-
duration space missions.
RESULTS
In view of the limited data about autonomic
cardiovascular control in relation to mental stress in
space, a hypothesis that mental load may alter
cardiovascular neural response in microgravity was
tested on 5 crew members before, during, and after
spaceflight over three 10- to 11-day European Space
Agency missions (Odissea, Cervantes, and Delta) to
the International Space Station. This investigation
examined cardiovascular responses to mental
arithmetic tasks and found no effect in space when
compared to baseline testing results for heart rate,
mean arterial pressure, and Heart Rate Variability
(HRV) parameters.
Parallel studies on the same subjects for up to 25
postflight days found heart rate (HR) increased only
with the standing position in early postflight, and
researchers concluded this as typical response to
upright stress after returning to gravity and full
tolerance was reestablished after 4 days. Symptoms
such as dizziness, loss of balance and/or vision, or
consciousness from uncompensated fall in blood pressure disappeared rather quickly after flight,
but it was unclear how long changes in dynamic HR control needed to recover. A simple paced-
breathing method was used to study respiratory control on the autonomic heart rhythms and data
collected 10 days prior to launch, then 1 and 25 days upon return to Earth showed that in spite of
increased HR and associated reduction in the rhythmic fluctuation of heart rate with breathing
(known as Respiratory Sinus Dysrhythmia or RSD), respiratory-mediated blood pressure dynamics
were unchanged after short-duration spaceflight. Results suggested that a fundamental neural
control deficit from microgravity deconditioning was less likely, and post-flight reductions in RSD
and blood-pressure control of heart rate were actually appropriate autonomic adjustments that
accounted for the altered blood flow regulation after spaceflight, which typically resolve within 25
days after landing.
(^) ESA astronaut Pedro Duque during the
Cardiocog experiment in 2003. NASA image.