Brain Fog, Flow State, & Acupuncture - The Treatment & Science of Brain Fog

Introduction: Brain Fog, Flow, and Your Nervous System

Brain fog feels, as some of my patients describe it, "like trying to read in a dim room". The ideas are there, but they never quite come into focus. Another patient described it as, "swimming in split pea soup", something is mentally weighing you down and slowing response on comprehension.

For many people, that fog shows up after viral illness, chronic fatigue, neuroinflammatory conditions, or the hormonal shifts of perimenopause. At the other end of the spectrum is flow state - those rare stretches where attention feels clear, the body and mind move as one, and time loosens its grip.

In my clinical work, I find it helpful to treat brain fog and flow as living on the same set of pathways, just tuned in opposite directions. When those pathways are stable, flow becomes easier to enter and stay in. When they are unstable, fog becomes the default.

In this article I want to walk you through that framework in simple language - the 4 pathways and 8 neurotransmitters that sit underneath both brain fog and flow - and then show you how acupuncture can act on each of those pathways in turn.

You can think of it like a sound system. Brain fog is not one broken speaker. It is the whole board slightly out of tune. Flow is what happens when the levels come back into balance and the song feels like it finally “clicks” into place.

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Pathway 1: Vagal Afferents - Restoring the Body’s Rhythm

The first pathway is the Vagus nerve.

This is the main feedback line from your organs up to your brain - carrying a constant stream of information about heart rhythm, breathing, gut movement, and whether your internal systems are stable and free from signals of imbalance.

When your body’s internal signals are clear and steady, your nervous system has an accurate read on how you're feeling and functioning. One way to measure this is through heart rate variability (HRV), which reflects the small changes in time between each heartbeat. HRV is closely tied to breathing and tends to be higher when your body is calm but alert. A higher HRV is a sign that your Vagus nerve is functioning well, helping your body handle stress and recover more effectively.

Research shows that people think more clearly and perform at their best when their nervous system is balanced - when the system that prepares you for action (sympathetic) and the system that helps you rest and recover (parasympathetic) are working in coordination rather than competing. Frontiers+1

We see similar patterns in music performance, yoga, and other flow-like activities. When people are deeply absorbed, their heart rhythm becomes more organized, and heart rate variability often increases or moves toward a more coherent pattern. PMC+1

In brain fog, especially after infections like COVID, this coherence is often disrupted. Many patients with long COVID or ME/CFS show low HRV and signs of sympathetic nervous system overdrive aka, ‘Wired but Tired’, where the fight, flight, or freeze reaction is overactive, and the ‘rest and digest’ is under active. This leads to a state of simultaneously anxious, cloudy, and fatigued Nature+1

Vagal signaling does more than steady the heart. When the Vagus fires, it releases acetylcholine onto immune cells and into tissues. That acetylcholine binds to α7 nicotinic receptors and triggers what is called the cholinergic anti-inflammatory pathway - a reflex that lowers inflammatory cytokines like TNF-alpha, IL-1β, and IL-6. Cell+3PubMed+3JCI+3

In practical terms, better vagal tone means less inflammatory “static” hitting the brain. Circulation improves, oxygen delivery to the cortex steadies, and the body’s alarm signals quiet down. That is the physiological opposite of fog.

In long COVID, there is now evidence that viral persistence and inflammation can reduce serotonin levels by diverting tryptophan down the kynurenine pathway. That drop in serotonin appears to weaken vagal signaling to memory centers like the Hippocampus and may help explain the combination of fatigue, low mood, and cognitive dulling many patients describe. Cell+2pennmedicine.org+2

Flow state, in contrast, behaves like gentle vagal training. Breathing naturally deepens, muscles soften, and attention narrows to one meaningful task. That combination activates the Vagus, stabilizes heart rhythm, and lowers inflammatory output over time.

Like a thermostat that finally starts reading the room correctly again, the Vagus nerve lets the brain match its internal settings to what is actually happening in the body.

How acupuncture acts on the vagal pathway

This is exactly where acupuncture can help.

When I place needles at specific points that influence breathing and the auricular branch of the Vagus - for example, points like Lu 7, Ki 6, and the Sympathetic ear point on the wrist, ankle, and ear, respectively - we see measurable changes in autonomic tone.

Clinical and experimental studies using auricular Vagus needle placement show reductions in heart rate and increases in overall HRV, consistent with stronger parasympathetic input. Frontiers+4Heart Rhythm Open+4PMC+4

From there, the signal travels into the nucleus Tractus Solitarius in the brainstem, and then outward into the wider autonomic network. That efferent pathway (brain to body), is the same cholinergic anti-inflammatory reflex described in Vagus nerve stimulation research, where activating this pathway lowers cytokine release and protects tissues from inflammatory injury. JCI+1

Clinically, what patients feel is simple: a softer breath, a slower pulse, and a quiet sense that the “background noise” has been turned down.

You can think of vagal-focused acupuncture like putting your nervous system’s metronome back on the table. Once that rhythm is steady, it becomes much easier for the rest of the system to fall into time.

Pathway 2: Spinal and Brainstem Pathway - Tuning Arousal and Pain

The second pathway lives in the spinal cord and brainstem.

This is the throttle that sets your overall level of arousal - too low and you feel dull and sleepy, too high and you feel wired and scattered.

At the center is the Locus Coeruleus (LC), the brain’s main source of norepinephrine (NE). When norepinephrine (think adrenaline) output is stable, attention can lock onto a task and stay there. When it is unstable, you either cannot get started or cannot settle. Flow appears when the LC-NE system is operating in a middle zone: enough norepinephrine to keep you engaged, but not so much that you tip into stress. Frontiers+1

Dopamine partners with this system. Each small win during a task - a correct note, a clean sentence, a smooth movement - triggers a dopamine pulse that makes the effort feel rewarding. That dopaminergic feedback loop is what makes flow feel both productive and enjoyable.

In brain fog, this loop is often blunted. Inflammatory signals can dampen dopamine and disrupt norepinephrine regulation, so effort feels heavy and unrewarding. Pain makes this worse. Chronic pain constantly pulls attention away from higher tasks and keeps the brainstem locked in a defensive posture.

Here the spinal pain-modulation system is critical. Sensory input from the body travels up through the dorsal horn of the spinal cord, but it is also modulated from above. Descending pathways from the Periaqueductal Gray and Rostral Ventromedial Medulla release endorphins and serotonin into the spinal cord and brainstem, while suppressing substance P - a neuropeptide that amplifies pain and inflammation. Wiley Online Library+3ScienceDirect+3PMC+3

During deep engagement, whether athletic, creative, or contemplative, these descending circuits activate. Endorphin levels rise, substance P falls, and pain signals are gated before they fully reach conscious awareness. People often describe this as “forgetting about their pain” while immersed in something they care about.

Flow, then, is not just a mental experience. It is a carefully tuned arousal and analgesic pattern in the brainstem and spinal cord, where norepinephrine, dopamine, serotonin, and endorphins all lean in the same constructive direction.

Like adjusting both the brightness and the volume on a screen, this pathway decides how sharp your internal picture is and how loud the background noise feels.

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How acupuncture acts on the spinal and brainstem pathway

Acupuncture interacts directly with these circuits.

When I insert needles at SI 3, UB 62, or LI 4, the mechanical and electrical signals travel up A-delta and C fibers into the dorsal horn. From there they engage the same Periaqueductal Gray and Brainstem Nuclei that regulate descending inhibition. ScienceDirect+2Frontiers+2

Electroacupuncture at low frequencies has been shown to preferentially release endorphins and enkephalins that bind μ and δ opioid receptors, inhibiting substance P release and dampening pain. Higher frequencies can recruit κ opioid and norepinephrine mediated mechanisms. ScienceDirect+2PMC+2

Human and animal studies consistently show decreases in pain scores along with reductions in substance P and increases in β-endorphin after treatment. PMC+2Wiley Online Library+2

Clinically, that means more bandwidth for cognition. When the constant pull of pain is eased, the brainstem can re-tune arousal toward focused engagement instead of defense.

You can think of spinal-brainstem focused acupuncture like turning down a buzzing fluorescent light in the next room. The moment it quiets, you realize how much effort you were spending just trying to ignore it.

Pathway 3: Neuroimmune Pathway - Calming Inflammation’s Noise

The third pathway is neuroimmune.

In many patients with brain fog, the underlying issue is not a lack of willpower, but ongoing inflammatory signaling in the nervous system.

Cytokines like IL-1β, IL-6, and TNF-alpha are essential for fighting infection and repairing tissue, but when they stay elevated they start to change how the brain works. They alter neurotransmission, activate glial cells, and shift energy use away from higher cognitive functions toward defense. The result is what immunologists call “sickness behavior”: fatigue, slowed thinking, low motivation, and often a low mood that feels qualitatively different from classic depression. Frontiers+2Herald Open Access+2

In conditions such as long COVID, ME/CFS, autoimmune illnesses, and some perimenopausal states, this pattern is common. Long COVID research, for example, has reported both elevated inflammatory markers and changes in tryptophan metabolism that reduce serotonin availability, correlating with brain fog and other cognitive symptoms. PMC+3Cell+3pennmedicine.org+3

Flow interacts with this pathway in three main ways:

First, by reducing chronic stress. Stable flow experiences tend to lower baseline cortisol and sympathetic drive over time, which reduces stress-amplified cytokine release. ScienceDirect+1

Second, by engaging the vagal anti-inflammatory reflex we discussed earlier. When the vagus fires steadily, acetylcholine acts on α7 nicotinic receptors on immune cells and glia, actively turning down cytokine output. Cell+3PubMed+3JCI+3

Third, by rebalancing neurotransmitters that talk directly to the immune system. Serotonin, dopamine, norepinephrine, GABA, and endorphins all have receptors on immune cells and can shift them toward a more regulated, resolution-oriented profile. Herald Open Access+1

In long COVID, a 2023 Cell paper showed that restoring serotonin - either pharmacologically or by supporting tryptophan metabolism - improved cognition and memory in many patients. Cell+1

From a clinical perspective, the key idea is that inflammation does more than make you feel fatigued. It raises the baseline ‘noise’ in the nervous system, making it harder for clear, focused thought to break through

Like trying to have a quiet conversation in a busy café, neuroimmune dysregulation makes every internal signal compete with a constant background buzz.

How acupuncture acts on the neuroimmune pathway

Acupuncture has a growing evidence base for modulating that immune noise.

Meta-analyses in animal models of depression and inflammatory conditions show that acupuncture can reduce pro-inflammatory cytokines such as IL-1β, IL-6, and TNF-alpha in both blood and brain tissue. Frontiers+2Herald Open Access+2

Clinical studies in humans with conditions like chronic pain, fatigue, and allergic inflammation also report reductions in inflammatory markers after treatment courses. SpringerLink+2PMC+2

Mechanistically, much of this seems to run through the same vagal cholinergic anti-inflammatory pathway described in basic science work: acupuncture needle input at Sj 5, GB41, and St 36 recruits vagal afferents, which then trigger α7 nicotinic signaling on macrophages and microglia, turning down cytokine production at the source. Frontiers+4PubMed+4JCI+4

In practice, patients describe this as a gradual lightening. Brain fog softens, fatigue feels less oppressive, and flares become less frequent or less intense.

You can think of neuroimmune-focused acupuncture as helping the immune system remember the difference between “emergency” and “ordinary life” again, the way a neighborhood calms after a fire alarm that has been stuck on for too long.

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Pathway 4: Monoaminergic and GABAergic Pathway - Rebalancing Brain Chemistry for Clarity

The fourth pathway is where most people’s attention goes first: the brain’s core neurotransmitters.

In reality, brain fog is not a single neurotransmitter problem. It is what happens when the whole conversation between acetylcholine, serotonin, dopamine, norepinephrine, GABA, glutamate, substance P, and endorphins loses coherence.

Acetylcholine is the spotlight of attention and learning. It helps you encode new information and keep the right things in focus. In menopause, declining estrogen can reduce acetylcholine synthesis and receptor sensitivity, which is one reason word-finding and memory lapses become more common. In long COVID, interactions between the virus and nicotinic receptors may further blunt cholinergic tone. Cell+2pennmedicine.org+2

Serotonin provides emotional steadiness and cognitive flexibility. Long COVID and chronic inflammation can lower serotonin by diverting tryptophan down the kynurenine pathway, leading to both mood changes and cognitive slowing. Cell+2ScienceDirect+2

Dopamine is the drive to engage. When dopamine is suppressed by inflammation or chronic stress, everything feels like pushing through sand. Norepinephrine sharpens signal-to-noise, but when it spikes in the wrong pattern, it produces anxiety instead of clarity.

GABA is the brain’s ability to say “not now” to irrelevant signals, while glutamate powers learning and plasticity. Too little GABA or too much disorganized glutamate feels like being mentally flooded. Substance P carries pain and stress signals; endorphins soften them and create a sense of embodied safety.

In flow, these systems line up:

• Acetylcholine helps lock onto the task at hand.

• Dopamine rewards progress.

• Norepinephrine stays at a steady, optimal level.

• GABA silences distractions.

• Glutamate drives learning in the specific circuits you are using.

• Serotonin and endorphins rise toward the end of the experience, sealing it with calm satisfaction while substance P recedes. PMC+3ScienceDirect+3Frontiers+3

  
  

Functional brain imaging studies of acupuncture show a similar pattern on the network level. Stimulation at specific points has been shown to modulate the default mode network and its anti-correlated task networks, shifting connectivity in regions like the Medial Prefrontal Cortex, Posterior Cingulate, Anterior Cingulate, and Hippocampus. These are the same hubs involved in mind wandering, pain processing, and executive control. SAGE Journals+5PMC+5PMC+5

That network-level rebalancing is another way of describing a more coherent monoaminergic and GABAergic landscape.

Like an orchestra where each section is finally following the same conductor, the brain’s chemistry during flow is not louder - it is more synchronized.

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How acupuncture acts on the monoaminergic and GABAergic pathway

Repeated acupuncture has been shown, in animal and human studies, to influence the expression of enzymes and receptors tied to dopamine, norepinephrine, serotonin, and GABA, as well as to increase endogenous opioid activity. PMC+5ScienceDirect+5PMC+5

For example, needling at Pc 6, Sp 4, and active scalp points along sensory-motor and frontal regions (Du 20-Du 24, GB 8-GB 9, & St 8) has been associated with changes in default mode network connectivity and improvements in mood and cognitive performance in patient groups with depression and chronic pain. PMC+3Frontiers+3PMC+3

HRV-focused acupuncture trials also suggest that by stabilizing autonomic tone, we can indirectly support monoaminergic balance, since these transmitters are tightly coupled to autonomic state. Liebert Publishing+3PMC+3PubMed+3

In the clinic, this often shows up as a shift from “wired and tired” to “awake and grounded” over the course of a treatment series. People report clearer word retrieval, more consistent focus, and a return of curiosity.

You can think of this pathway as color correction for the mind. The image was always there, but the tint was off. Acupuncture helps the brain rediscover its true palette.

Bringing It Together: Why Flow and Acupuncture Belong in the Same Conversation

When you put these four pathways together, a simple pattern emerges.

Flow is what happens when:

• The Vagus nerve is sending a clear, steady signal of internal safety.

• The spinal and brainstem systems are tuned to a band of calm alertness and effective pain gating.

• The immune system has turned down excess cytokine noise.

• The monoaminergic and GABAergic networks are synchronized instead of fighting each other.

  
  

Brain fog is what happens when those same pathways are working against one another.

Acupuncture and flow both work by helping those systems remember how to align.

In my practice, I think of acupuncture as the external reset - a way to send precise, patterned signals into the nervous system and reopen pathways that illness, stress, or hormones have narrowed. Flow-building practices are then the internal training - the daily activities that keep those pathways active and strengthen them over time.

Acupuncture reintroduces the rhythm. Flow helps you learn to keep the beat on your own.

For patients living with post-COVID brain fog, chronic fatigue, neuroinflammatory illness, or perimenopausal cognitive changes, that combination can be powerful. It does not erase the underlying condition, but it can restore a sense of mental brightness and agency - proof that clarity is still present in the system and can be reached through the body’s own circuitry.

Like watching a dimmer switch slowly rise, you do not go from dark to daylight in one step. But with each small increase in coherence, more of the room becomes visible again.

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Citations

Flow, HRV, and autonomic balance

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Long COVID, serotonin, and brain fog

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Cholinergic anti-inflammatory pathway and vagus nerve

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Acupuncture, HRV, and autonomic regulation

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Acupuncture, pain modulation, and neuropeptides

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Acupuncture, inflammation, and cytokines

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