The main objective of this study is to determine the relationship between cognitive functioning and the NIRS/ EEG signal under hypoxic circumstances.
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
functioneren onder hypoxie
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The main study parameters are cognitive functioning (working memory, tracking,
vigilance, planning), blood oxygen saturation levels (cerebral), brain activity
of the frontal cortex, heart rate and blood pressure.
Secondary outcome
peripheral oxygen saturation levels, heart rate and blood pressure.
Background summary
Previous research has shown that mild to moderate hypoxia (90-75%) decreases
human performance by impairing physiological and cognitive functioning. It is
important to investigate these effects because various complex tasks are
performed at mild to moderate levels of hypoxia (e.g. pilots, people working at
altitude). Cognitive functioning might be altered by the impaired cerebral
oxygen saturation in the blood. Near infrared spectroscopy can be used to asses
this cerebral oxygen saturation. Simultaneously assessing the
electro-encephalograph at the same positions on the cortex can be of an added
value. The purpose of this study is to measure how cognitive functioning is
affected by mild to moderate hypoxia and to determine if these effects are
reflected in NIRS and EEG brain signals. Especially of interest is the cerebral
oxygen saturation of the frontal cortex.
Study objective
The main objective of this study is to determine the relationship between
cognitive functioning and the NIRS/ EEG signal under hypoxic circumstances.
Study design
This study has a single blind design. The conditions of mild and moderate
hypoxia and the order of the tasks will be balanced across subjects
Intervention
Partly deoxygenated air will be inhaled by the subjects with a special
breathing mask. Oxygen saturation levels will be manipulated and actively kept
constant at (1) 98%, baseline sea level, (2) 90%, as found in subjects residing
at an altitude of approximately 2500-3500m and (3) 80%, as found in subjects
residing at an altitude of approximately 4000-5000m. Oxygen saturation will be
measured in the frontal cortex and peripherally. The oxygen saturation level of
the frontal cortex will be assessed with near-infrared spectroscopy (NIRS).
Peripherally, oxygen saturation will be measured at the ear using a pulse
oximeter. During each of the three saturation levels, subjects will perform
three different cognitive tasks (N-back, tower of Hanoi and VigTrack). To
assess the activity of the frontal cortex electro-encephalography (EEG)
measurements will be done simultaneously.
Study burden and risks
Before the study, subjects will be screened, based on their medical history, to
ascertain their health. After inclusion the subjects will be administered to
the mild and moderate hypoxia levels. The subjects are instructed that hypoxia
will induce deep breathing and an increase of heart rate, and that these
symptoms should be interpreted as physiologically normal. Other symptoms as
nausea, dizziness, temporarily reduced vision, hyperventilation and syncope
(fainting) are more severe and are an indication of acute hypoxia. In case
symptoms as mentioned above appear, the experiment will be ended immediately.
The mild and moderate levels of hypoxia are sufficient to expect an impaired
cognitive functioning due to the lower oxygen saturation both peripherally and
cerebrally.
kampweg 5
3769 DE Soesterberg
Nederland
kampweg 5
3769 DE Soesterberg
Nederland
Listed location countries
Age
Inclusion criteria
1. Non smoking, or stopped at least 1 years ago.
2. Aged between 18 and 30 years, at day 01 of the study.
3. Apparently healthy based on the anamnesis (see appendix).
4. Having given their written informed consent.
5. Wiling to comply with the study procedures.
6. Willing to accept use of all anonymous data, including publication, and the confidential use and storage of all data.
7. Willing to accept the disclosure of the financial benefit of participation in the study to the authorities concerned.
Exclusion criteria
1.Medical problems (amongst others, cardiovascular and respiratory diseases).
2.No use of prescribed medication in the last 14 days prior to start of the study, with the exception of the use of aspirins and ibuprofen and oral contraceptives (o.a.c.). These can be taken until 72 hours prior to the start (this does not apply for o.a.c.) .
3.Use of drugs.
4.Sickness in the last 7 days prior to the start of the study.
5.Not willing to except the transfer of relevant study results to their physician.
6.Having donated blood in the last 14 days
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL26501.028.09 |