Page 187 - International Space Station Benefits for Humanity, 3rd edition.

Countering Neurological Maladaptation
European Space Agency (ESA) research has been The findings of this research
uncovering important aspects of how the structure
and function of the brain adapt due to exposure to are crucial for enabling the
spaceflight conditions; e.g., how central processing safe planning of future human
of information is altered under spaceflight conditions
and on return to Earth. The findings of this research exploration missions beyond low-
are crucial for enabling the safe planning of future Earth orbit, and also have clinical
human exploration missions beyond low-Earth orbit,
and also have clinical implications on Earth within a implications on Earth within a wide
wide range of neurological disorders. range of neurological disorders.
The brain functions through electrical signals to perform
every voluntary and involuntary activity in our body.
This electrical activity is important for complex brain
function and helps us to characterize brain dynamics
and brain states made visually accessible through
techniques such as EEG and MRI. Changes in electrical of voluntary movements) when performing tasks in a
activity are a normal part of human daily life—e.g., brain visually attentive state in orbit. The Brain-DTI (preflight/
wave changes associated with waking up and falling postflight) experiment uses advanced MRI methods
asleep. However, changes in electrical activity can also to help accurately determine and map the effect
be a sign of some maladaptation, which could result of spaceflight-induced changes in brain structure
in, or be a sign of, cognitive dysfunction. and function on the motor, vestibular and cognitive
systems. Brain-DTI has already discovered alterations
Two ESA ISS experiments—Neurospat and Brain-
DTI—have already produced positive results published in vestibular and motor-related regions of the brain,
in several renowned peer-reviewed journals in 2016 which could account for space motion sickness as
and 2017. Neurospat compared inflight to ground well as reduced vestibular function and motor control
EEG measurements and discovered a greater abilities in space and at re-entry. This research has also
contribution from the motor cortex (involved in control been backed up by similar results from parabolic flight
campaigns. Vestibular and motor-related regions of the
brain seem to be critically involved. Hampered sensory
inputs from the inner ear could have an effect on brain
areas where integration of the different sensory inputs
takes place. Observations of problems with motor
abilities in returning space crew suggest plausible
alterations of structure and function of the cerebellum
(responsible for coordination and fine motor control).
Motor imagery, widely used in sports, could prove
to be a useful countermeasure in this neurological
adaptation. This technique involves mentally visualizing
a specific motor task, and mentally feeling muscle
contractions in advance of performing that task.
It has been proven that motor imagery activates
similar brain regions, as is the case with executed
movements. This technique is finding its way into
different rehabilitation and pain management scenarios
such as post-stroke motor rehabilitation. The technique
An MRI scan using of a volunteer’s brain for the offers an inexpensive and rather simple approach to
BRAIN-DTI experiment using tractography to prepare space travelers for the absence of gravity
show neural networks. and re-adaptation phase when coming back to Earth.
Transcranial magnetic stimulation also offers a possible
Image credit: University of Antwerp
countermeasure by allowing non-invasive stimulation
of an area of the cortex through the scalp by means

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