The Nervous System Has More Than One Dysregulated State

The Nervous System Has More Than One Dysregulated State

by Sarah Phillips

How this was researched: This article draws on peer-reviewed research in autonomic neuroscience, psychophysiology, and polyvagal theory. Cited studies are linked throughout. This content is educational, not medical advice. If you are navigating dysregulation that significantly affects your functioning, working with a healthcare provider is appropriate and important.

TL;DR — The nervous system doesn't have one dysregulated state — it has several, each with distinct physiology, distinct triggers, and distinct needs. Treating them as one thing is why so many regulation strategies work sometimes and fail at others. This is the map: what each state actually is, what's happening in the body, and what that means for how you respond to it.

Why the category matters

Most wellness advice about stress, anxiety, and regulation treats the problem as a single condition with a single solution. Calm down. Breathe. Rest. These aren't wrong — they're just aimed at one state out of several, which is why they work reliably for some people in some situations and do nothing in others.

The nervous system is an adaptive system. It doesn't have one way of going wrong — it has multiple defensive responses, each evolved for a different type of threat. What looks like "being stressed" from the outside can be any of several distinct physiological conditions. They share some surface features. They have different underlying mechanisms. They need different interventions.

Understanding which state you're in is not a therapeutic exercise. It's practical information. The regulation tool that works well for sympathetic overdrive is not the same tool that works for freeze. Using the wrong one isn't just ineffective — it can deepen the state you're trying to leave.

The autonomic framework

The nervous system's stress responses are primarily mediated by the autonomic nervous system (ANS) — the system that regulates involuntary functions including heart rate, breathing, digestion, and the body's threat response.[1] The ANS has two primary branches that most people know: the sympathetic nervous system (activation, mobilisation, threat response) and the parasympathetic nervous system (rest, digestion, recovery).

Polyvagal theory, developed by Stephen Porges, adds important nuance: the parasympathetic system itself has two distinct pathways — the ventral vagal pathway (social engagement, connection, regulated calm) and the dorsal vagal pathway (shutdown, immobilisation, the freeze response).[2] This distinction matters because "parasympathetic activation" isn't always recovery. Dorsal vagal shutdown is parasympathetic — and it feels nothing like rest. A fuller treatment of polyvagal theory and what it means practically.

The states described below map onto this framework. They are not discrete boxes — the nervous system moves along a continuum, and people often cycle between states within a single day. But understanding the distinctions changes what you reach for.

The states

Sympathetic overdrive

What it feels like: Running hot. Reactive. Can't exhale. Small things feel disproportionately large. The body is prepared for a threat that isn't there, or has already passed.

What's happening: The HPA axis has activated, releasing cortisol and adrenaline. The sympathetic nervous system is dominant. Heart rate is elevated, breathing is shallow, the amygdala is running threat detection at high sensitivity.[3] The prefrontal cortex — responsible for perspective, proportionality, and decision-making — has reduced functional capacity under this load.[4]

Why it's distinct: This is the most commonly named stress state, and the one most regulation advice targets. Breathwork, cold exposure, exercise — these are all sympathetic down-regulators. They work here. They may not work in other states.

What helps: Anything that activates the parasympathetic system — slow exhalation (which stimulates the vagus nerve), sustained physical movement, sensory cues that signal safety. Scent compounds that act on GABAergic and HPA pathways are particularly well-matched to this state. Micro-resets for CALM states.

Hypervigilance

What it feels like: Can't settle, even in safe environments. Scanning. A low-grade alertness that doesn't switch off. Difficulty tolerating uncertainty or unpredictability. Sleep that's light and easily disrupted.

What's happening: The threat-detection system is stuck in an elevated baseline. The amygdala is operating at heightened sensitivity — filtering incoming information for potential danger even when none is present.[5] Unlike acute sympathetic overdrive, hypervigilance is a chronic elevated baseline rather than a spike. Cortisol patterns are dysregulated across the day rather than acutely elevated.

Why it's distinct: Hypervigilance can look like anxiety from the outside, but the physiological profile is different from acute sympathetic activation. The nervous system isn't responding to a current threat — it's operating as if threat is always imminent. Standard calming strategies may provide temporary relief without shifting the baseline.

What helps: Consistent safety signals over time — routine, predictability, physical environments that the nervous system has learned to associate with no-threat. Sensory cues used repeatedly in calm moments build the associative library the nervous system draws on. This is a state where the conditioned response aspect of functional fragrance is particularly relevant: not acute intervention, but baseline recalibration through repeated cue. Why functional fragrance gets more effective over time.

Cognitive fog

What it feels like: Scattered. Can't access clarity. Thoughts that don't connect. The sensation of looking for something in a drawer and forgetting what it was mid-search. Difficulty holding context across tasks.

What's happening: This is a state of cognitive depletion rather than acute activation. Acetylcholine — the neurotransmitter most directly involved in sustained attention and working memory — is depleted or its transmission is impaired.[6] The prefrontal cortex is functional but under-resourced. Unlike sympathetic overdrive, the nervous system isn't in a threat response — it's depleted.

Why it's distinct: Fog is often mistaken for laziness or distraction. It's neither. It's a resource problem, not a motivation problem. The interventions for sympathetic overdrive (calming, down-regulation) will not help here — and may deepen the fog. What's needed is activation of the attention-supporting neurotransmitter systems, not further relaxation.

What helps: Compounds that support cholinergic function and alerting without inducing anxiety — 1,8-cineole (eucalyptus), which inhibits acetylcholinesterase;[7] citrus-derived hesperidin and limonene, which suppress sympathetic excess without sedating. Movement also helps — even brief physical activity increases acetylcholine and norepinephrine availability. Micro-resets for FOCUS states.

Freeze / shutdown

What it feels like: Can't move. Can't decide. Staring at a task list without being able to start any of it. A sense of collapse or disappearing. Emotional numbness. Sometimes described as "checked out" or "not here." More on why this happens with task lists specifically.

What's happening: The dorsal vagal pathway has activated — the oldest and most primitive branch of the parasympathetic system, associated with immobilisation in the face of inescapable threat.[2] This is not relaxation. It's a survival response: when a threat is perceived as overwhelming and unavoidable, the nervous system may shift into conservation mode rather than mobilisation. Heart rate drops, digestive function may slow, cognitive access narrows.

Why it's distinct: Freeze is parasympathetic, which makes it easy to confuse with rest or calm. It isn't. It's a collapsed state, and the interventions for sympathetic overdrive are the wrong tool — applying further calming to a freeze state can deepen it. What's needed is gentle activation, not deactivation.

What helps: Gentle mobilisation — slow movement, temperature change, orienting to the physical environment (looking around, noticing five specific things). The goal is to shift from dorsal vagal shutdown toward the ventral vagal social engagement system, which requires activation rather than further calm. This is one of the states where standard regulation advice most reliably fails. Micro-resets for grounding and orienting.

Emotional flooding

What it feels like: Overwhelmed by feeling to the point where thinking is not available. Crying that won't stop or can't start. Rage that feels disproportionate. The sensation of being inside the emotion rather than observing it.

What's happening: Amygdala activation has exceeded the window of tolerance — the range within which the nervous system can process experience without becoming overwhelmed.[8] The prefrontal cortex has gone significantly offline.[4] The emotional response is not being regulated by higher cortical processing — it's running on its own circuitry.

Why it's distinct: Flooding looks like sympathetic overdrive but is more acute and more cognitively impairing. The key distinction: in sympathetic overdrive, thinking is degraded but present. In flooding, it's largely unavailable. Asking someone who is flooded to "think it through" or "use their coping skills" is asking them to use a system that is temporarily offline.

What helps: Reducing sensory input and demand first — quiet, stillness, physical safety. Then the same tools as sympathetic overdrive once the acute flooding has subsided. The sequence matters: attempting regulation strategies during active flooding is often ineffective. Waiting for the acute response to pass slightly before intervening is more reliable.

Sensory overload

What it feels like: Everything is too loud, too bright, too much. The capacity to filter is gone. Irritability that seems to arrive from nowhere. The need to leave, to have silence, to stop receiving input.

What's happening: The nervous system's filtering capacity — the thalamic gating mechanism that normally screens sensory input for relevance — has become saturated or impaired.[9] Stimuli that would normally be filtered out are registering as signals. The brain is processing more than it can efficiently manage, producing a defensive response to input that isn't inherently threatening.

Why it's distinct: Sensory overload is often present alongside other states but has its own distinct feature: the primary driver is input volume, not threat interpretation. Reducing input is more effective than attempting emotional regulation. This is a state where environment matters more than internal strategy.

What helps: Reducing environmental input first — dimmer light, quieter space, fewer competing demands. Physical sensation that is controlled and predictable (not unpredictable, which adds more input) can help recalibrate the threshold. Near-field scent is useful here precisely because it's intimate rather than ambient — one controlled sensory signal rather than another layer of noise.

Transition dysregulation

What it feels like: Not quite here. Carrying the residue of the last thing into the next thing. Fragmented. The meeting that ended ten minutes ago is still occupying space that the current moment needs. Or the trip you just returned from hasn't fully resolved.

What's happening: The nervous system doesn't switch contexts cleanly. Moving between activation states — work to home, social to solitary, travel to ordinary life — requires a physiological transition that takes longer than the cognitive one.[10] The autonomic system is still running the prior context's settings while the external environment has changed. This mismatch produces a specific kind of dysregulation: not acute stress, not fog, but fragmented presence. Why you can't decompress between work and home.

Why it's distinct: Transition dysregulation is the most undernamed of these states, which is partly why it's so common without being addressed. It doesn't look like stress from the outside. It often looks like distraction, mild irritability, or difficulty being present. The intervention isn't calming or activating — it's marking the transition itself. The nervous system needs a signal that context has changed.

What helps: Deliberate transition rituals — physical, sensory, or behavioral cues that consistently mark the shift from one context to another. This is the state most directly addressed by GROUND: the orienting signal of fig leaf and bergamot, the autonomic modulation of cedar and vetiver, used consistently at re-entry points. Micro-resets for transition and re-entry.

What Aerchitect addresses — and what it doesn't

The three Aerchitect mists are formulated for sympathetic overdrive (CALM), cognitive fog (FOCUS), and transition dysregulation (GROUND). These are the three most common daily states for people navigating chronic overstimulation — which describes most of the people this brand is built for.

Hypervigilance is addressed indirectly: consistent use of CALM at high-activation moments builds the conditioned safety signal over time that hypervigilance needs, but it isn't a primary intervention for the baseline.

Freeze, emotional flooding, and sensory overload are outside the primary scope. Functional fragrance can provide a gentle sensory cue during or after these states — but these states require different primary interventions. Naming this is not a limitation to apologise for. It's what honest formulation looks like.

For a guide to which mist addresses which state and how to use them: The Best Functional Fragrance Mists for Nervous System Regulation. For help identifying which state you're in right now: How to Choose Between CALM, FOCUS, and GROUND.

A note on cycling

Most people don't live in one state. A day that starts in sympathetic overdrive after a difficult commute, moves into cognitive fog by mid-afternoon, hits transition dysregulation at re-entry, and ends in hypervigilance-driven sleep disruption is not unusual. The states interact and compound.

This is why the premise of a single regulation tool for all of it — one scent, one supplement, one practice — doesn't hold. Not because any single tool is inadequate, but because the problem isn't one thing.

FAQ

Is dysregulation the same as anxiety?

Not exactly. Anxiety is a psychological and physiological experience that can involve several of these states — most commonly sympathetic overdrive and hypervigilance. But dysregulation is broader: cognitive fog, freeze, and transition dysregulation are all forms of dysregulation that don't necessarily involve anxiety as most people would name it. The distinction matters because anxiety-focused interventions (breathing, cognitive reframing, medication targeting the anxiety response) may not address the full picture of what's happening. Anxiety and the nervous system — a fuller treatment.

Can I be in more than one state at once?

Yes. States overlap and layer. Sympathetic overdrive and sensory overload often co-occur. Hypervigilance frequently underlies other states as a baseline. Cognitive fog can develop on top of chronic sympathetic activation as the system depletes. The descriptions above are meant to help you identify the primary driver, not to imply clean separation.

Why does the same regulation strategy work sometimes and not others?

Almost certainly because you're in different states on different occasions. A breathwork practice that reliably helps with sympathetic overdrive may do nothing for freeze, and may actually be frustrating during emotional flooding when cognitive access is limited. This isn't the practice failing — it's the wrong tool for the current state. Matching intervention to state is the variable most regulation advice skips.

Is freeze the same as burnout?

Related but distinct. Burnout is a chronic depletion state — the nervous system has been running at high activation for too long without adequate recovery, and has progressively lost capacity.[11] Freeze is an acute shutdown response. Burnout often includes periods of freeze, cognitive fog, and emotional flooding, and may eventually produce a chronic low-grade freeze-like baseline. They share features but have different timescales and different primary interventions. For more on burnout specifically: Why Rest Doesn't Fix Burnout.

What if I don't know which state I'm in?

Start by noticing activation level and cognitive access. Are you hot and reactive (sympathetic overdrive) or flat and unavailable (freeze/shutdown)? Can you think, or is thinking impaired (flooding)? Is everything too much (sensory overload) or are you just scattered (cognitive fog)? The table below is a rough triage:

Primary sensation Likely state
Hot, reactive, can't exhale Sympathetic overdrive
Scanning, can't settle, sleep disrupted Hypervigilance
Scattered, foggy, can't connect thoughts Cognitive fog
Flat, can't start, numb Freeze / shutdown
Overwhelmed by feeling, can't think Emotional flooding
Everything too loud, too much Sensory overload
Not quite here, carrying the last thing Transition dysregulation

References

[1] Porges, S.W. — The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-Regulation. Norton (2011).

[2] Porges, S.W. — "The polyvagal perspective." Biological Psychology (2007). https://pubmed.ncbi.nlm.nih.gov/16290959/

[3] McEwen, B.S. — "Physiology and neurobiology of stress and adaptation: central role of the brain." Physiological Reviews (2007). https://pubmed.ncbi.nlm.nih.gov/17928583/

[4] Arnsten, A.F.T. — "Stress signalling pathways that impair prefrontal cortex structure and function." Nature Reviews Neuroscience (2009). https://pubmed.ncbi.nlm.nih.gov/19455173/

[5] Rauch, S.L. et al. — "Exaggerated amygdala response to masked facial stimuli in posttraumatic stress disorder." Neuroreport (2000). https://pubmed.ncbi.nlm.nih.gov/10790869/

[6] Hasselmo, M.E. — "The role of acetylcholine in learning and memory." Current Opinion in Neurobiology (2006). https://pubmed.ncbi.nlm.nih.gov/16962767/

[7] Moss, M. et al. — "Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults." International Journal of Neuroscience (2003). https://pubmed.ncbi.nlm.nih.gov/12690999/

[8] Siegel, D.J. — The Developing Mind: How Relationships and the Brain Interact to Shape Who We Are. Guilford Press (2012).

[9] Stein, B.E. & Meredith, M.A. — The Merging of the Senses. MIT Press (1993).

[10] Sonnentag, S. — "Psychological detachment from work during leisure time." Current Directions in Psychological Science (2012). https://journals.sagepub.com/doi/10.1177/0963721411434979

[11] Maslach, C. & Leiter, M.P. — "Understanding the burnout experience: recent research and its implications for psychiatry." World Psychiatry (2016). https://pubmed.ncbi.nlm.nih.gov/27265691/

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These statements have not been evaluated by the Food and Drug Administration. Aerchitect products are not intended to diagnose, treat, cure, or prevent any disease.