HEG Neurofeedback: How Training Prefrontal Blood Flow Supports Brain Regulation

Hemoencephalography (HEG) is a form of neurofeedback that measures changes in blood flow and oxygenation within the prefrontal cortex — the region directly behind the forehead that supports attention, planning, decision-making, impulse control, and emotional regulation.

Unlike EEG neurofeedback, which records the brain's electrical activity, HEG measures the brain's vascular and metabolic response. When a region of the cortex is engaged in a cognitive task, neuronal activity increases and local blood flow rises to meet that demand — a process known as neurovascular coupling.

HEG makes this process visible in real time through a sensor placed on the forehead, allowing the individual to learn how to influence activation in the prefrontal cortex through feedback.

There are two main types. Near-infrared HEG (nirHEG) measures oxygenated haemoglobin using infrared light. Passive infrared HEG (pIR HEG) measures heat emitted from the prefrontal region. Both are non-invasive and do not introduce any signal into the brain — they only record physiological changes.

How does HEG Neurofeedback support brain function

Sustained attention, mental endurance, and emotional steadiness under pressure all depend on how efficiently the prefrontal cortex can activate and maintain itself when demand is high. For many people, this isn't a matter of effort or motivation — it reflects how readily the brain can recruit the blood flow and oxygen that region needs to function well. When that process is inefficient, focus becomes harder to sustain, mental fatigue sets in more quickly, and emotional reactivity can increase.

HEG training strengthens this capacity directly. By providing real-time feedback on prefrontal oxygenation, it gives the brain a way to repeatedly practise the mechanisms behind increasing local blood flow during sustained effort. Over time, this builds the brain's ability to activate and maintain prefrontal function more reliably — supporting more consistent attention, greater cognitive endurance, and steadier regulation when it matters most.

HEG Neurofeedback research summary

Research into HEG is still developing, but several studies have explored its effects on brain activity and clinical outcomes.

Voluntary control of prefrontal activation. Early work by Toomim and colleagues demonstrated that individuals can intentionally increase cerebral blood oxygenation in targeted areas of the prefrontal cortex through nirHEG feedback, providing initial support for the mechanism that underpins training.¹

ADHD and executive function. A 2021 randomised study by Skalski and colleagues compared ten sessions of HEG biofeedback with physical activity training in 120 children aged 9–15, half of whom had ADHD. Children with ADHD showed lower baseline performance in vigilance, visual search, multitasking, inhibitory control, and working memory than neurotypical peers. After training, both groups improved on these cognitive measures following HEG, while the physical activity condition did not produce statistically significant changes.²

Mental health presentations. A 2023 study in NeuroRegulation documented outcomes from 66 clients receiving pIR HEG in a private clinical setting. After five sessions, statistically significant changes were reported in anxiety, depression, limbic overload, and coping self-efficacy. Clients completing ten to fifteen sessions showed more robust changes across these measures, along with improvements in general self-efficacy and reductions in dissociation.³

Migraine. HEG has been studied for migraine since the early 2000s. Carmen's observational work reported substantial reductions in migraine frequency and severity in adults using pIR HEG, and a later controlled study by Walker and Lyle in 2016 found similar reductions in migraine without aura — making this one of the more developed areas of HEG outcome research.⁴ ⁵

Inhibitory control in older adults. A more recent randomised study combined HRV biofeedback with nirHEG over ten weeks in healthy older adults. The combined intervention produced gains in inhibitory control on interference tasks compared with an active control condition, supporting the use of HEG within multi-modal regulation programmes.⁶

It is important to note: . Many HEG studies have used small samples, short training courses (often five sessions or fewer), or designs without active control conditions. With the exception of attention-related work, there are few large randomised controlled trials, and findings are best described as promising rather than definitive. Outcomes also vary between individuals and depend on the structure within which training is delivered.

How HEG Neurofeedback is applied at the nctNeurofeedback Clinic

At the nctNeurofeedback Clinic, HEG is used as a complementary modality within a broader, assessment-led neurophysiological approach to brain training, rather than as a standalone intervention.

Treatment planning begins with a detailed assessment of how regulation is functioning across attention, cognitive endurance, emotional control, and recovery following effort. From there, a programme is designed that may include HEG alongside EEG neurofeedback, depending on the patterns identified.

This integrated approach reflects how regulation actually works in the brain. Prefrontal activation does not function in isolation — it interacts with cortical networks regulated through electrical activity and with autonomic processes regulated through the heart and breath. When HEG is included in a broader plan, it is targeted to what it is best suited to support: sustained prefrontal activation, cognitive endurance, and stability of executive function under demand.

-------

References

1. Toomim H, Mize W, Yeekwong P, et al. Intentional increase of cerebral blood oxygenation using near infrared hemoencephalography (nirHEG): A preliminary investigation. Journal of Neurotherapy. 2004.

2. Carmen JA. Passive infrared hemoencephalography: Four years and 100 migraines. Journal of Neurotherapy. 2004.

3. Mize W. Hemoencephalography (HEG) and executive function training. Journal of Neurotherapy.

4. Ros T, Baars BJ, Lanius RA, Vuilleumier P. Tuning pathological brain oscillations with neurofeedback. Frontiers in Human Neuroscience. 2014.

5. Micoulaud-Franchi JA, Jeunet C, Pelissolo A, Ros T. EEG neurofeedback for cognitive and emotional regulation: A systematic review. Current Psychiatry Reports. 2021.