Hi Achilleas, please try to read the papers by Prof. Vellutti. He is one of the expert in this field. Perhaps, you could discuss with him!

https://www.researchgate.net/profile/Ricardo_Velluti/publications

Hello Dr. Seithikurippu,

Thank you for your response, your help is much appreciated!

I have just downloaded his book "The auditory system in sleep" through my university's library resource and it seems very useful for my research. I will try and contact him for help. I'm still testing the machine and the reasons for not distinguishing sleep stages may be because of mistakes in the electrode application and i will be doing a new recording session tonight. Hopefully, the data will show clearly the different stages of sleep. Hopefully it is not the case that  Neuroelectrics' STARSTIM is unsuitable for sleep studies.

Any help/tips on using the Neuroelectrics' software features to help with distinguishing sleep stages would be appreciated.

I'm having this issue with the EOG data during sleep. As you can see in the picture the LEOG (Ch1) and REOG (Ch8) and RVEOG (Ch7) all have the same voltage peaks.This effect happens for most of my 5h recorded sleep. How is this possible? Where are the eyes looking? Shouldn't at least 1 of the electrodes show the opposite voltage peak? Is this some sort of artifact?

Answer from an expert: Jasmit Parmar

if the visualization filters are the two listed on the bottom then they are incorrect. The low frequency filter seems to be set at 2.0 Hz but that will cause signal attenuation and you would never be able to pick variations such as slow wave sleep, K complexes or even the rapid eye movements because they actually are at times slower than 2.0 Hz even if it the documentation says they move faster.

I would suggest decreasing the lower filter to the range of 0.3-0.5Hz to allow proper signal movements to come through and the high frequency filter could remain but if they are issues such as fuzzy signals it could be reduced to 30.0Hz. No sleep activity reads faster than 30Hz. The only waves that are faster than 13-14Hz are beta and I would presume they do not move faster than 20Hz especially in sleep plus you see a limited about of them.

Hi Achilleas, 

This answer is concerning same voltage peaks withing your EOG data. The issue that you have observed may be related to the montage used to monitor eye movement. By Rechrschaffen and Kales, a referential recording is made from an electrode placed 1cm lateral and superior to the outer canthus and referred to the ipsilateral ear. A second channel records activity from 1cm lateral and inferior  to the contralateral outher canthus referred to the ipsilateral ear. This electrods placement  shows eye movement as out of phase potential, increasing interpreter's confidence in identifying REM onset. 

If eye movement are recorded by electrodes placed near each outher canthus, absence of phase reversal lessens  the ease with which visual identification can be made. 

Kind regards, Tatyana

Hi Leila,

No the top pictures are just random ones, it was just to showcase the softwares features. The correct values are in the final picture (0.5 - 35Hz).

I have stopped using STARSTIM for sleep recognition and im now using Biotrace+ Nexus-10 for that using EOG neg/pos electrodes to assign HEOG and VEOG.

I now have different issues. The settings are much more advanced in this and i am not sure which filters+settings to apply to facilitate real-time recognition of REM. Any tips/advice?

Sorry for the late reply.

Did you figure out the setting or  still need help ?

No I've figured it out. Thank you though! :)

     http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2869.2010.00831.x/full

Achilleas,

              The above URL may be relevant to your  request. Additionally, I have appended  a copy of information from my files.

Regards,

  Ed

----------------------------------------------------------------------------------------------------                             The Ever Present  Past                                                                                                                          

Dr. Paul MacLean's triune brain theory describes a three- layered process of encephalization ... A neocortical (neomammalian layer), which covers an older limbic (paleomammalian) system, and which in turn is layered above even more ancient diencephalic (reptilian) structures. Originally each of the underlying layers controlled its own type of somatic behavior and supporting autonomic system, but as each new layer was evolving it gradually suppressed or inhibited full expression of the one beneath it. Nevertheless, according to the theory, the human condition still continues to reflect the persisting influences of its ancestral origins. In that regard, added Maclean, we put so much emphasis on ourselves as unique creatures possessing spoken and written languages that , like rich men denying their poor relatives , we are loath to acknowledge our animal ancestors.

Accordingly, while recalling that Dr. Nathaniel Kleitman observed that the trick was not to explain sleep but to explain consciousness, by applying MacLean's triune brain theory in terms of Kleitman's observation, it becomes possible to move human consciousness up the evolutionary ladder to its present-day neocortical-neomammalian position on the top rung. In other words, what we call 'sleep' must actually be comprised in what can only be described as being older and more primitive states of ancestral consciousness.

Additionally, we know that sleep reflects two distinct phases, namely NREM sleep and REM sleep, and that the latter can be further divided into tonic REM and phasic REM (dreaming sleep). Therefore, the question becomes one of inquiring as to their order in ascending the evolutionary ladder of human consciousness.

To address the question it may be observed that : (1) the closest phase of sleep to complete neocortical consciousness is phasic REM (dreaming) sleep, which (2) means that tonic REM and NREM were older predecessor/ancestral consciousness stages, and (3) since tonic REM is absent thermoregulation, and as Parmegianni observed 'contradicts the paradigm of homeostasis' while NREM enhances homeostasis with only a slight decrease in thermo-sensitivity, we may conclude  that the oldest state of suppressed ancestral consciousness is now reflected by tonic REM, next oldest is NREM,  then phasic/dreaming REM ( MacLean’s paleomammalian / limbic consciousness), and finally where we are to day , namely neocortical consciousness.

In other words, speaking evolutionary-wise , the oldest , and what we call tonic REM sleep, can be considered as being the predecessor of NREM sleep, and NREM sleep then likewise as being the predecessor of phasic (dreaming) REM sleep; and accordingly all three as being reflective of former ancestral evolutionary stages in the development of human consciousness .