Sleep, Stress, and Neurofeedback

© Martin H. Gremlich MSc Nat ATP,
Human Biologist

Clinical observation suggests that many physical and physiological conditions come along with simultaneous sleep issues. Some of the most prominent conditions are TBI, PTS, concussive events, trauma, abuse, GI issues, toxic issues, medication, anxiety and depression, etc.

It has become a credo in the world of medical practitioners, psychiatrists, and therapists that such conditions would cause sleep issues. The assumption of such a cause and effect has no logical or scientific grounds. It is (like many others in the field) a conclusion jump based solely on frequent simultaneous appearance.

With this article I propose a scientific explanation of the only known functional cause that does have the physiological potential to cause sleep issues: “Stress”.

I explain the ergonomic “mechanism” leading to sleep issues and why every physical, mental, or emotional condition whatsoever must contribute to “stress”, hence, indirectly and variably affects sleep.

Lastly, I suggest tactics to assist improving sleep and consequently support recovery from any condition (diagnosed or not) by employing conventional non-intrusive neurofeedback.

Ergonomy – the Logical Science Behind

Ergonomy is the logical science behind this article. The name derives from the Greek noun “ergon” meaning “function, purpose, process”; the Latin adverb “ergo” (therefore) evolved from it.

Anatomy answers the scientific question “how is it built?”. Physiology answers the question “how does it work?”. Ergonomy finds answers to the question “why” – to what purpose, goal, and under what conditions – does it happen?”.

Ergonomy is the “mathematics” of biology so to speak. Its goal is to make functional sense of raw data provided by Anatomy and Physiology. Ergonomy considers Laws of Nature (e.g. physics, biochemistry etc.) to study the dynamics of an organism’s anatomy and physiology in function performing the activity of living, of that sleep is a fundamentally vital component.

Ergonomic understanding of anatomy and physiology in function is mandatory to understand processes such as “stress”, “sleep”, and ultimately functional efficacy of neurofeedback.

What is Sleep ?

Sleep is not something that passively happens to an organism. Sleep is something an organism actively does. Sleep is an array of specific highly coordinated activities. Activities cannot become sick. Logically, inefficient sleep cannot be medically treated. Yet, neurofeedback is an excellent option.

When sleeping, the CNS carefully orchestrates the activities of inner digestion, processing and distributing of resources, growing, restoring, waste processing, detoxification, memory clean-up, healing, trauma resolving, learning (evaluation and consolidation of recorded experience) etc. etc. with the mandatory purpose to functionally reset the organism for the next awake period.

These inner maintenance activities require a specific endocrinal and neurological profile of the entire organism. Sleep physiology is antagonistic to physiology of activation (arousal), which physiologically enables the organism to act and move around (see Figure 1 below). This antagonism is why we cannot simultaneously sleep and be awake.

In order to do sleep work, the organism needs to physiologically deactivate its motor system and most of its External Attention System EAS (except auditory). Parts of memory must be taken off-line for servicing. It takes time to “spool” the organism down from an “awake” (aroused) physiological profile and transition it into a profile that physiologically allows sleep activity.

It also takes time to re-activate the organism’s agility physiologically e.g. in case of imminent danger. Consequently, with EAS, motor-system, and parts of memory functionally off-line, the organism becomes extremely vulnerable when doing sleep work.

To understand the actual cause of sleep issues it is crucial to understand that sleeping is a high-risk activity for a living organism.

Therefore, whenever a CNS determines presence of significant perceived external and anticipated threats, it never commands a physiological deactivation of the organism (sleep); the CNS keeps the organism awake, alert, and physiologically ready to act (see “Stress” below) as long as resources allow activation to be maintained.

On the other hand, any mental or physical condition (diagnosed or not) requires extra repair time to restore the organism; it requires extra sleep, which the CNS instantly commands in a low-risk situation. No such condition could possibly cause any sleep issues. Our ancestors could not have survived long enough to have offspring if this was physiologically possible.

The only functional condition enabling an individual to develop sleep issues at all is a high degree of physiological arousal as result of a high stress score (see “Stress” below). To understand the process, let’s first look at a fundamental functional principle a human organisms is subjected to:

The Functional Antagonism: Activation vs. Restoration

A human organism has a finite maximum performance capacity for both, agility performance (act, move) and restorative performance (sleep). The ultimate limitations are dictated by the anatomical and physiological design or “blueprint” of the organism.

The Laws of Nature (e.g. thermodynamics) do not allow an organism to maintain any unused performance capacity. This forces the organism to alternate vital activities. The CNS must at all times trade-in some performance in one activity spectrum (e.g. restorative capacity – “sleep”) for an increased performance in the other (awake agility capacity) and vice versa.

Figure 1 below illustrates the functional range between the two antagonistic performance extremes. Note: High agility arousal physiologically inhibits awake “cognitive” or mental performance, which is best near the transition zone (green arrow) and includes mental REM sleep activity (dreaming), which is vital for memory actualization (e.g. learning, trauma relief).

Figure 1

Maximum performance in either antagonistic activity can hardly ever be reached by an organism and can never be maintained. At every moment of life, an organism is dynamically fluctuating somewhere “in-between” the two physiological extremes – simplified e.g. 70% activated and 30% restoring or 55% restoring and 45% activated.

Momentary positions on the graph are highly dynamic and naturally vary throughout a day. This variation reflects in what is known since Vedic times as “circadian” or “diurnal” rhythms, of which e.g. sleep cycles are integral components.


Every possible momentary position between the two functional extremes has its own systemic physiological profile. The profile affects all measurable parameters such as blood pressure, body temperature, blood profusion, endocrinal spectrum, neurotransmitter spectrum, metabolic performance, oxygenation, muscle tonus, intestinal activity, etc. etc. and of course brainwave patterns. If one parameter (e.g. a hormone density) changes, all others must change in accordance, too.

The momentary physiological profile of an organism – relative activation vs. restoration – is at all times dynamically directed by the CNS. It never ever happens “automatically” even though it is never subjected to willpower or conscious awareness. Contrary, availability of willpower, thought, and conscious awareness is only possible in a limited mid range of arousal, which the CNS only directs in a low-risk situation.

These “mental” functions require a specific physiological low awake-arousal profile (see green arrow Figure 1 above). Note: Being awake and active does not mean being “conscious” or “aware”. That is why “stress” not only affects sleep, it also physiologically affects mental and cognitive performance.

Stress, the Lifesaver

The term “stress” means “the strain a force executes on an object”, which is very misleading when it comes to human “stress”. What we commonly call “stress” is in fact a mandatory ongoing life-maintaining dynamic three-step process that loops with lightning speed all life long. The process involves

o Complex data assessment to establish a stress score
o Subsequent corresponding physiological activation – the stress score response
o Ultimately execution of an action to reduce stress score – a response behaviour

Assessment of the resulting stress score launches the next loop.

To understand how this process may affect sleep – and to determine how best to assist with neurofeedback – let’s look at the three-step process in detail.

Stress Score:

The CNS must continuously assess the momentary totality of present and anticipated functional threats to the organism. Further, it must define the subjective severity of threats by comparing them to the momentary agility potential of the organism.

The CNS performs this mandatory complex ongoing threat assessment with lightning speed non-stop all life long, awake or asleep. The result of each assessment – after a long chain of subsequent events – actively initiates what we commonly call “behaviour”. The lifesaving purpose of the process is obvious: Act (behave) to avoid being harmed by threats.

The CNS must consider two different sets of information to establish relative severity of threats:

o Perceived and anticipated environmental threats (“external” incl. social)
o Internal threats (anatomical and physiological condition) that reduce the momentary agility potential of the organism.

The stress score is the accumulated totality of all individual threat severities at this moment. It represents the risk total the organism is momentarily exposed to as subjectively assessed by its CNS. The CNS requires this stress score to determine global urgency to act and to decide required speed and intensity of a response action.

Any anatomical or physiological issue (including e.g. TBI) reduces the organism’s agility potential. Hence, it increases relative severity of every assessed threat. A health issue cannot not cause any sleep issues but must relatively increase stress scores.

Emotional trauma on the other hand does not reduce agility of the organism. However, trauma influences the threat severity assessment, for that a mammalian (human) brain relies on memory data as reference. Hence, trauma directly influences stress scores as-well.

The stress score itself (the total of an individual’s assessed threat severities) is exclusively individual, subjective, and absolutely non-conscious. A stress score is variable and largely unpredictable.

Based on an established momentary stress score, the CNS instantly commands a corresponding stress score response.

Stress Score Response:

The stress score response is always the result of the assessed urgency to act, not the result of any specific threat.

In order to enable the organism to act according to the established stress score, the CNS must command an accurate physiological profile. In other words, the CNS must direct the organism to become physiologically ready to act.

This always requires adjustment of every measurable parameter (incl. blood pressure, PH level, endocrinal profile, neurotransmitters, brainwaves, etc.). This is where e.g. “emotions” come into the equation. Emotions are one of the many results of the specific endocrinal “soup” the CNS directs as physiological stress score response. Emotions are vital integral parts of a stress score response, even though most of them remain below the threshold of conscious awareness.

Emotions serve among many other functional purposes to activate recording of the response action to follow (enable learning). Emotions are also motivators for a coordinated action (behaviour) to follow; e.g. “making a face” and “taking a stance”, which are vital communication behaviour.

A stress score response is dictated by the design of the anatomical and physiological blueprint of the organism. In other words, stress score response as such is largely common to all humans and is as an isolated process step basically predictable.

Response Behaviour:

Once the organism has been activated (aroused) by the stress score response, it is now physiologically capable to act. The CNS decides and directs a corresponding action (behaviour), which the CNS anticipates to successfully counteract a selective threat, which in turn will reduce the subsequent new global stress sore.

For reasons of finite resources and limited performance capacity (physics), the CNS must prioritize fast reduction of the global stress score over significant reduction. That is why a high stress score predictably always seemingly leads to “overreaction” and more “irrational”, “impulsive”, “aggressive”, or “obsessive” behaviour as judged by others such as family members, teachers, or therapists.

With a mammalian (human) CNS any response behaviour heavily depends on memory data. Response behaviour is where e.g. “learning”, “conditioning”, “addictions” etc. and ultimately neurofeedback finally flow into the process.

Response behaviour depends on individual life experience and learned behaviour. As an isolated process step it is only to a very limited degree predictable.

“Stress”, the entire three-step process is a fundamentally vital functional life principle required not only to allow macro behaviour but also to allow micro behaviour such as a coordinated heart-beat or breath.

How can “stress” – an absolutely vital lifesaver that has the functional purpose to protect against any harm – cause sleep issues and as a non-negotiable consequence become a brutal killer?

To understand the process and to determine promising tactics to counteract, let’s look at another functional principle of Laws of Nature every life organism is subjected to:

Inverse Proportionality: Actual Performance Potential vs. Required Activation

The actual agility performance potential of a human organism is highest at the beginning of an awake-period. Mandatory the potential must decreases over the awake period caused physically and biochemically by exhaustion of metabolic resources and “wear and tear”.

The CNS must continuously increase physiological arousal inversely proportional to the agility potential loss over the awake period in order to have the organism maintain a certain awake performance.

After a period of awake time the organism reaches the “cross-over” or “fatigue” point (see Figure 2 below). Beyond that point performance physically can no longer be maintained even with maximum possible arousal. It is the latest moment where restoration would be possible without causing excessive exhaustion and damage to the organism that requires extra restorative work (sleep) to successfully cope with.

Beyond the fatigue point, the CNS has to continue to increase physiological arousal (see Stress Score Response above) to have the organism at least perform at its continuously decreasing maximum. The destructive shears open wider the longer the organism stays awake and keeps performing beyond the fatigue point instead of demobilizing and starting restorative activity (sleep).

Figure 2

Beyond the fatigue point only an excessively high stress score (see “Stress” above) has the potential to reduce momentary relative significance of restorative needs on a stress score and “motivate” the CNS to set priority on commanding an ongoing awake performance.

Persistent Stress, the brutal Killer by Sleep Deprivation

“Persistent stress” is at all times exclusively anticipated threat (fears, anxiety, etc.) that cannot be successfully counteracted by an immediate action (e.g. flight, fight, or play dead). Persistent stress is a selective killer by sleep deprivation.

The killer mechanism is as simple as it is effective. A persistently high physiological arousal – “over-arousal” – does physiologically not allow sufficient restorative activity over time (see Figure 1 and Stress Score Response above) and non-negotiably leads to the decay of the organism.

“Over-arousal” means a higher physiological arousal than what is momentary functionally useful. The effect of over-arousal on the organism is analogue to driving a car with the gas pedal full down while regulating the speed with the brakes. It wastes excessive amounts of precious metabolic resources, creates excessive wear and tear, and leads to “glowing hot” brakes and engine and at the end of the day – too hot to allow maintenance.

Persistent stress creates greater need for restoration while simultaneously reducing restorative efficiency.

The deadly shears: Over-arousal causes a downshift of the performance potential, which requires a yet higher stress score and consequently leads to a further upshift of physiological arousal (see “Stress response” and Figure 2 above). Figure 3 illustrates this effect.

Figure 3

How does accumulated over-arousal at the end of the awake day create sleep issues ?

Over-arousal and Sleep Issues

Sleep cycles are circadian or “diurnal” maintenance cycles that follow an astonishingly precise timing of physiological patterns. All mammalian species sleep in “cycles”.

To understand the effect of over-arousal on sleep, as a simplified but quite illustrative model imagine sleep cycles to start always exactly where the organism is in terms of physiological arousal at intended start of sleep.

Physiological over-activation “shifts” the entire Hypnogram – the sequence of sleep cycles – up into the physiological awake range (see Figure 4 below).

Consequently, only the “deeper” parts of sleep cycles “dip” into the physiological range where sleep work is physiologically possible; in its extreme it may lead to tossing and turning awake all night.

The “top” of sleep cycles lies now in the awake range where mental activity potential is at its peak. REM sleep with its resolving mental activity “dreaming” turns into futile mental awake activity such as rumination or worry, which subsequently enforces a high stress score and consolidates high physiological arousal.

Figure 4 above models the functional origins of virtually every noticeable common sleep issue on record.

Inversed, the graph also illustrates how the practice of any efficient stress relief technique during the day, such as a nap, breathing, HRV training, certain types of Yoga, and of course the most efficient of all – skilful deep meditation – are functionally granted to improve physical, mental, and emotional health.

Such techniques reduce accumulation of physiological arousal during the day, which consequently “dips” the Hypnogram back towards where it belongs at bed time (see Figure 5 below). Their primary functional effect is a reduction of the stress scores and wear and tear during practice.

This leads among other benefits granted to a relatively lower arousal at intended start of sleep, which increases sleep efficiency and restorative sleep achievements with all subsequent systemic and benefits.

Sleep Support with Neurofeedback

Non-intrusive neurofeedback is the only technology-based tool available today that has at least theoretically a potential to assist with sleep quality and efficiency improvement. A skilful neurofeedback provider can assist clients by targeting at the same effect a deep meditation can have – a reduction of physiological arousal during the session.

Figure 5

This tactic has the granted dual benefit of directly entraining relaxation and indirectly lowering relative arousal at next bed time leading to improved sleep efficiency and better systemic restoration.

The major challenge for a neurofeedback provider:

We cannot directly influence a client’s anticipated persistent threats (e.g. existential or social fears etc.) to lower stress scores. The only influence on client’s stress scores we have is via imminent environmental factors during the session. However, since a stress score is a total, reducing any isolated environmental threat component alone already lowers the momentary total stress score.

Consequently, the success of a relaxation session crucially depends on the optimization of the session environment. The session environment ultimately decides whether we “get through” to the client with the message of our feedback signal at all (irrespective of the protocol used).

During a session a client’s CNS considers the following environmental factors as relevant:

  • Presence, attitude, stance, arousal, and behaviour of the provider (and any other perceived human – e.g. parent) throughout the entire session.
  • Session location (including e.g. lighting, commotion, electromagnetic pollution, smells, noise, training chair, position in the room, wall colours, decoration, distractions, etc. etc.).
  • Schedule, timing, and duration of the session’s components.
  • Time allowed for familiarisation with the environment and “spool down” (e.g. breathing, HRV, etc.) before and “spool up” after neurofeedback runs.
  • Choice of feedback signals – visual vs. audio.

Visual entrainment requires engagement of the EAS (external attention system), which can only work if the organism is physiologically activated (see Figure 1 above). Visual entrainment entrains physiological arousal. It counteracts the session goal. Not a good idea.

The audio attention system of the human organism is both anatomically and functionally separate. It is at all times activated and works also when sleeping. Engagement of the audio-system is physiologically arousal-neutral. Logically, the most efficient relaxation training is an eyes closed audio entrainment.

  • Choice of optimal devices to deliver an audio feedback signal for optimum positive impact (type of headset etc.).
  • Choice of feedback sounds (kind, quality, pitch, volume, etc.).

Neurofeedback signals are at all times no more and no less than relatively insignificant components of the session environment (sounds or changes on a screen). If any or several of the environmental factors above are adverse, any protocol chosen can have little to no relaxing effect; client’s CNS would simply not assess the feedback signals as being relevant.

Choice of Relaxation Protocols

There are three primary criteria to consider

  • Avoid any intrusive feedback modality.
    Intrusive modalities are methods such as Microtesla, LENS, photic stimulation, etc., which produce unnatural energetic environmental impacts, which – no matter how “micro” the Teslas are – represent additional functional challenges (potential threats) to the CNS. Any stimulation is excitory. Such technologies functionally must drive stress scores and arousal up. They are unsuitable for relaxation training.
  • Avoid any referencing protocol.
    Z-score, sLoretta, Life-Loretta, or brain map based protocols are referencing to databanks. Databank norms are data of individuals with an awake physiological profile (see Figure 1 above) with respective brainwave patterns. Referencing to a databank trains towards an aroused norm, which is counterproductive to the session target. There are no reliable restorative reference brain data available today.
  • Avoid any warning sounds during a session.
    Any audio warning (e.g. “artefact” or “falling asleep” warning) as well as any computer system warning must be muted completely during the session. Such alarms sky-rocket stress scores instantly and subsequently jolt client’s organism back into high physiological arousal with a flush of adrenalin, norepinephrine etc. Audio warnings annihilate previous relaxation achievements of the session instantaneously. Equipment and protocols that do not allow disabling of audio alarms are unsuitable for relaxation entrainment.

Protocols – What do we train where to ?

Being under observation – in particular in a clinic or lab with sensors attached to the body – is a primeval threat for a human CNS. A CNS that concludes being observed does never command optimal relaxation (sleep). Therefore, to be successful with relaxation entrainment, we cannot count on neurophysiology, endocrinology, brain wave and ROI phrenology, fMRIs, etc. for reliable guidance.

The most reliable information available is provided by empirical statistics. In other words: We do not know why or how some protocols work but we do know that they likely do work, which is the only ultimately relevant practical information we need.

Protocol Suggestions

Based on statistical information, three decades of functional sleep research, and my professional experience with neurofeedback sleep support I suggest for best results simple 1, 2, or 3 channel audio amplitude training, eyes closed.

The common denominators of statistically effective relaxation protocols are

  • “SMR” training – up-training 12-15 Hz amplitudes picked up at or near the midline anywhere between Fz and Pz
  • 6 – 10 Hz up training and its sophisticated form “Alpha-Theta” picked up at or near the midline at central, parietal, or occipital locations.

Protocol Enhancements

Combining the primary training (above) with a simultaneous subtle Beta and High beta amplitude down training (16 Hz and faster) at the same locations may increase efficiency. A session with runs of both protocol types in sequence may further increase session efficiency.

The effect of a relaxing audio protocol can be enhanced by tuning and embedding feedback tones to calming meditational tunes. Important: The provider decides what feedback tones and tunes are “relaxing”; it’s not client’s choice based on their conscious “likes”. Client’s “likes” may be very counterproductive or unsuitable to harmonically embed feedback tones.

Needless to say, some basic knowledge of effects of sound, rhythms, and musical harmonics on the CNS and a certain “musical ear” are beneficial skills for a provider venturing into the professionally quite demanding field of audio training.

How do we assess training success?

With both relaxation protocols types (SMR and Alpha-Theta), brainwave spectra do not follow the primary entrainment.

SMR amplitudes do not increase (they may become more “lively”). With Alpha-Theta training Alpha amplitudes alternatingly even decrease against training to produce the desired “crossovers”. Despite this paradigm-killing phenomenon, a considerable physiological relaxation (low stress scores) can be achieved. However, training graphs do not necessarily reflect training success …

To be able to fall asleep requires a low physiological arousal that is even below that of an awake deep meditation (see Figure 1 above). Consequently, falling asleep during a session grants to reduce physiological arousal later that day at bedtime even more than if the client stays awake. (see Figures 1 and 5 above).

Falling asleep during the session is the greatest and most reliable sign of training success and is in direct functional accordance with the session’s target.

Does neurofeedback work while a client is sleeping?

I do not know of any logical argument indicating that neurofeedback audio training could possibly work any less efficiently while sleeping. Functional logics (ergonomics) strongly suggest that audio neurofeedback may principally work even more efficiently when asleep.

Visual entrainment, on the other hand, of course requires a fully engaged EAS, which in turn requires maintaining a high awake physiological arousal; it cannot work when sleeping. We cannot entrain deep relaxation with visual or somatosensory feedback signals.


No diagnosable condition has the physiological or psychological power to cause lasting sleep issues; “insomnia” certainly does not cause itself. However, every diagnosable condition must contribute via reduction of agility potential or increased relative severity of threats non-specifically and variably to a relative increase of stress scores.

Dictated by anatomy and physiology, high stress scores lead to high physiological arousal that keeps the organism physiologically awake, hence, non-negotiably hampers sleep efficiency.

Successful relaxation entrainment is symptom-independent. It targets at the functional cause of sleep issues by intending to lower stress scores during the session.

Relaxation entrainment does not require any complex protocols, hyper-sophisticated equipment and software, fMRI studies, or profound knowledge in physiology, neuroscience, endocrinology, psychology etc.

It requires basic understanding of a human organism in function (not taught at medical school) and a functional understanding of neurofeedback as an educational method – as core operand conditioning (as opposed to therapy). Sleep cannot be healed but sleep can be entrained. Keep in mind, the Latin word “doctor” does not mean medical professional. It means teacher. Neurofeedback certainly is a potent relaxation teacher’s tool.

A successful relaxation session acts in a greater non-conscious systemic context in harmony with the primary functional task of the CNS. The session entrains relaxation and supports systemic functionality of the entire organism by indirectly enhancing sleep efficiency and sleep achievements.

The positive long-term effects of a sequence of relaxation sessions go far beyond granted sleep improvement and accelerated healing of any diagnosed physical, mental, or emotional symptom. The multitude of oftentimes-unexpected positive global changes in the lives of your clients can be astonishing and extremely rewarding for both your clients and yourself.