The CSA investigation Space Health 

utilizes the Bio-Monitor system for 

physiological monitoring before, during, 

and after a mission to the space station to 

assess the effect of space travel on heart 

health. NASA ID: jsc2022e062020.
Publication Highlights

Human Research

 

Space station research includes the study of risks to human health that are inherent in space exploration. 

Many research investigations address the mechanisms of these risks, such as the relationship to the 

microgravity and radiation environments as well as other aspects of living in space, including nutrition, sleep, 

and interpersonal relationships. Other investigations are designed to develop and test countermeasures to 

reduce these risks. Results from this body of research are critical to enabling missions to the lunar surface 

and future Mars exploration missions. From the beginning of station to date, more than 800 articles have been 

published in the area of Human Research. 

The CSA investigation Cardiac 

and Vessel Structure and 

Function with Long-Duration 

Space Flight and Recovery 

(Vascular Echo) studies the 

effect of spaceflight on the 

stiffening of blood vessels, 

which can lead to elevated blood pressure and 

the progression of cardiovascular conditions. 

In a brief communication published in 

Aerospace Medicine and Human Performance, 

researchers compared two different types 

of ultrasound technologies (traditional 2D 

and advanced 3D) to see if imaging quality 

differences would reveal the effectiveness of 

a countermeasure used to reduce cephalad 

(headward) fluid shifts in space (i.e., 

venoconstrictive thigh cuffs). Due to its manual 

operation, traditional 2D ultrasound has 

resulted in measurement errors that impact the 

reproducibility of the studies. 

Figure 14. 2D and 3D imaging of the internal jugular vein in three crew 

members. 2D imaging was unreliable and it did not allow researchers to 

detect differences between baseline (black) and the effect of wearing thigh 

cuffs (gray). Image adopted from Patterson, Aerospace Medicine and 

Human Performance. 

In the study, researchers revealed that 

motorized and semi-automated 3D ultrasound 

identified a 35 percent size reduction of the 

internal jugular vein after three crewmembers 

wore thigh cuffs for four hours during 

spaceflight (Figure 14). These changes 

were missed by the 2D option. The finding 

indicates that 3D ultrasound can more 

adequately measure cardiovascular anatomy 

than 2D ultrasound and demonstrates that 

venous congestion (i.e., pooled blood in 

lower extremities not flowing to the heart) is 

effectively diminished by thigh cuffs. 

The large probe head, constant scan speed, 

and fixed contact with crucial body parts 

make the motorized 3D ultrasound superior 

to standard 2D technologies. This research 

demonstrates that 3D ultrasound allows 

non-expert sonographers to take precise 

measurements of challenging body parts to 

accurately assess vascular changes during 

spaceflight.

The ASI instrument Light Ions 

Detector for ALTEA (LIDAL), 

installed in the Columbus 

module in January 2020, 

was designed to measure 

cosmic particles, light and 

heavy ions from phosphorous 

(P) to iron (Fe), in a wide range of energies. 

In a new study published in Life Sciences in 

Space Research, researchers report on the 

functionality of the instrument. 

Patterson C, Greaves DK, Robertson AD, Hughson RL, Arbeille P. Motorized 3D ultrasound and jugular vein dimension measurement 

on the International Space Station. Aerospace Medicine and Human Performance. 2023 June 1; 94(6): 466-469. DOI: 10.3357/ 

AMHP.6219.2023. 

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Publication Highlights

Human Research

LIDAL takes into 

account the position 

of the detector inside 

station, which was 

moved along station’s 

axes X, Y, and Z, the 

geomagnetic region 

(high/low latitude), and 

time-of-flight (ToF) of 

detected ions. The 

time-of-flight parameter 

adds information about 

the kinetic energy 

or velocity of the 

particles, enhancing 

the recognition of 

ions fundamental to 

understanding the 

effects of radiation on the human body. 

LIDAL upgrades the particle detection 

capabilities of a previous investigation, 

ALTEA, by using three Silicon Detector 

Units between two plastic scintillators for 

the fast timing of ToF measurement. These 

enhancements increase the sensitivity to 

cosmic ray ions for improved data acquisition. 

Initial measurements of LIDAL with 17 

months of data collection confirm the highly 

variable radiation field of station. Researchers 

found that the measurements of particles 

differ depending on the orientation of the 

detector due to the shielding arrangement of 

station. This study distinguished, for the first 

time, forward particles arriving to station from 

Earth and backward particles going to Earth 

from station. The radiation field peculiarities 

depended on whether particles were 

influenced by the Earth’s shadow or passed 

through more mass inside the station as 

shown by LIDAL measurements. Additionally, 

flux and dose rate values are lowest at low 

latitudes and highest at high latitudes (Figure 

15), but the total integrated dose is larger 

at low latitudes because the space station 

Figure 15. Regions of high latitude in blue, low latitude in orange and the excluded South Anomaly (SAA) region in yellow 

and green. Image adopted from Di Fino, Life Sciences in Space Research. 

spends more time near the equator. 

The LIDAL detector system allows the 

conversion of measurements from particle 

charge and velocity to radiation risk indices 

to enable researchers to determine the level 

of radiation exposure for crewmembers and 

devise countermeasures. 

The ESA and Roscosmos 

investigation Brain-DTI 

measures structural and 

functional changes in the 

brain after spaceflight 

to search for clues of 

adaptation to microgravity, 

especially in areas of the brain involved in 

visual perception, balance, and orientation. 

In a new study published in Communications 

Biology, researchers examined brain 

functional connectivity changes of 

cosmonauts (Figure 16) after spaceflight and 

eight months later to learn which changes 

remained and which changes reverted to 

baseline. Functional connectivity, estimated 

through resting-state functional MRI, refers to 

the coordinated function that exists between 

Di Fino L, Romoli G, Amantini GS, Boretti V, Lunati L, et al. Radiation measurements in the International Space Station, Columbus 

module, in 2020-2022 with the LIDAL detector. Life Sciences in Space Research. 2023 May 6; epub: 30pp. DOI: 10.1016/j. 

lssr.2023.03.007. 

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Publication Highlights

Human Research

different regions of the brain. For example, 

distinct areas of the brain work in concert to 

enable walking or reading. 

Previous studies have revealed structural 

and functional changes after months in 

microgravity. Some of these findings are 

associated with microgravity-induced fluid 

shifts, such as larger ventricles, redistribution 

of cerebrospinal fluid, while other findings 

rather suggest possible neural adaptation, 

including gray and white matter increases in 

sensorimotor areas, and reduced activity of 

the vestibular system. In the current work, the 

researchers explored functional connectivity 

changes in a resting state that suggested 

adaptation in areas of vestibular and motor 

function as well as multisensory integration. 

An assessment of brain activity while at 

rest in 15 cosmonauts revealed decreased 

functional connectivity after spaceflight 

in the left posterior cingulate cortex, an 

area involved in change detection, longterm memory, and divergent thinking. This 

decreased connectivity persisted at the 

8-month follow-up. Additional decreases 

observed in the bilateral insula, which 

processes salient stimuli, returned to preflight levels after the mission. Increased 

connectivity was found in the right angular 

gyrus and was sustained during the follow-up 

period. This region is involved in verticality 

processing as well as detecting mismatches 

between actual and expected sensory 

outcomes. The sense of verticality has gained 

importance in view of the planned missions to 

the Moon and Mars during which crew landing 

capabilities must be optimal. A final analysis 

showed that the changes in functional 

connectivity were independent of structural 

changes in the brain during flight. Together, 

changes were mostly found in higher-order 

brain regions, suggesting adaptation at the 

level of multimodal integration. 

Figure 16. ESA astronaut Thomas Pesquet on the space station, showing 

on the tablet his brain scanned pre-flight for the BRAIN-DTI project.

These results demonstrate the adaptability 

and plasticity of the brain under extreme 

conditions and provide new insight into the 

workings of the central nervous system. This 

newfound knowledge may contribute to the 

development of targeted countermeasures 

or ways of monitoring brain adaptations 

to promote healthy brain function and 

adaptation, as well as improved treatments 

for vestibular disorders. 

Findings from various 

research studies tracking 

astronaut health in space are 

archived in the International 

Space Station medical 

monitoring investigation. 

This collection contains a 

wealth of knowledge regarding the effects 

of spaceflight on multiple body systems. 

A Roscosmos study classified as medical 

monitoring on station reported new findings 

about biomarkers of endothelial and immune 

function in the journal npj Microgravity. 

The lining of blood vessels, known as the 

endothelium, plays an important role in blood 

circulation and vascular injury recovery. 

Endothelial cells serve metabolic and 

endocrine functions through the exchange 

of metabolites and hormones between 

Jillings S, Pechenkova E, Tomilovskaya ES, Rukavishnikov IV, Jeurissen B, et al. Prolonged microgravity induces reversible and 

persistent changes on human cerebral connectivity. Communications Biology. 2023 January 13; 6(1): 46. DOI: 10.1038/s42003-022-

04382-w. 

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Publication Highlights

Human Research

the bloodstream and surrounding tissues. 

Despite its importance to human health, little is 

known about the impact of spaceflight on the 

endothelium. 

In the study, researchers examined the 

function of the endothelium and its interaction 

with the immune system by collecting 

indicators of blood flow and immune health 

(i.e., anticoagulant receptors, various white 

blood cells, and cytokine secretions). Blood 

samples were obtained from 15 crew members 

before and after spaceflight. 

Results showed increases and decreases 

in different blood-based indicators after 

spaceflight (Figure 17). Notably, these varying 

changes characterized the state of the immune 

system. That is, higher concentrations of 

biomarkers indicating endothelial dysfunction 

correlated with increased production of 

proteins that regulate immune responses. 

These results suggest a tendency toward 

increased blood clotting upon return to Earth. 

Changes to biomarkers involved in both 

endothelial function and inflammation may in 

turn affect the immune response. 

Understanding the effect of spaceflight on 

blood vessel damage and blood flow enables 

researchers to develop countermeasures 

that prevent coagulation during long duration 

missions to the Moon or Mars. 

Figure 17. Data on von Willebrand factor, a protein involved in blood flow 

arrest, and leukocyte concentrations before spaceflight (baseline), one day 

and seven days after spaceflight. Increased endothelial dysfunction tends to 

occur in tandem with increased production of multiple white cell types one 

day after spacelfight. Image adopted from Kuzichkin, npj Microgravity. 

Kuzichkin DS, Nichiporuk IA, Zhuravleva OA, Markin AA, Rykova MP, et al. Endothelial dysfunction markers and immune 

response indices in cosmonauts’ blood after long-duration space flights. npj Microgravity. 2022 November 2; 8(1): 1-9. DOI: 

10.1038/s41526-022-00237-0. 

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