2. measurement of sleep video

Question 2

sleep can be measured by:

Answer 2

1. polysomnography = EEG + EOG + EMG
2. behavioural analysis = movement detection + sensory threshold detection
3. autonomic function analysis = heart rate
4. core body temp analysis

Question 3

How does EEG work?

Answer 3

measure electrical activity of brain: EPSPs and APs are measurable as transmembrane currents in ECM, the summation of extracellular field potentials in vertically oriented pyramidal neurons can be recorded outside skull

• inverse from electrical current inside an individual neuron: neuronal down states (synchronized hyperpolarization) are measured as large upwards amplitude in EEG = slow/delta wave

Question 4

How are the different frequencies divided:

Answer 4

0-4 Hz = Delta (slow wave)
4-8 Hz = Theta (almost sleeping/REM)
8-12 Hz = Alpha (closed eyes waking)
12-35 Hz = Beta
> 35 Hz = Gamma (active waking)

Question 5

EEG power spectrum can be made with a fast fourier analysis. it is a :

Answer 5

the EEG signal is mathematically analyzed to decompose frequencies into diffferent power spectra. From a time domain to freq. domain.
- made separately for different vigilant states

Question 6

behavioural analysis consists of: movement detection and increased sensory threshold detection. What are possible measurment methods?

Answer 6

1. actigraphy
2. running wheel
3. infrared beam braking
4. increasing stimulus strength untill a reaction appears.