qEEG vs. EEG: What’s the Difference? | Round Rock, TX

By Mary Parker, LPC-S

People sometimes use “EEG” and “qEEG” as if they mean exactly the same thing. They are closely related, but the terms describe different parts of the process.

Understanding the distinction can also help clear up a bigger misconception: a colorful qEEG report is not a magical diagnostic scan.

What Is an EEG?

Electroencephalography, or EEG, records electrical activity from electrodes placed on the scalp. Clinical EEG has a long history in medicine and is commonly used in neurological evaluation, including situations where seizure activity is a concern.

The recording itself is the EEG data.

What Makes It “Quantitative” EEG?

qEEG refers to quantitative processing and analysis of EEG data. Software can examine characteristics such as frequency-band activity, relationships among recording locations, and other derived measures. Data may also be compared with reference databases depending on the method being used.

That analysis can generate graphs, tables, and the colored topographic maps many people associate with “brain mapping.”

Does qEEG Diagnose ADHD?

No single qEEG measure should be used as a stand-alone ADHD diagnosis. ADHD is heterogeneous, and proposed biomarkers such as the theta/beta ratio have shown inconsistent performance across populations and studies.

A 2025 critical review of qEEG biomarkers in ADHD likewise described qEEG as potentially informative while emphasizing that it is not a stand-alone diagnostic tool.

Is qEEG the Same as an MRI?

No. EEG measures electrical activity at the scalp with very high temporal resolution. MRI uses a completely different technology to create structural images, and fMRI examines blood-oxygen-level changes associated with activity. They answer different questions.

Why Do We Use qEEG in Neurofeedback?

At Infinite Potential, qEEG can provide additional physiological information that may help inform individualized neurofeedback planning. Neurofeedback then uses EEG sensors to record activity and provide real-time feedback tied to selected training targets.

The sensors record; they do not electrically stimulate the brain.

What Can Go Wrong With Overinterpreting a Map?

A colorful image can feel definitive. But artifact, recording quality, state during recording, analysis choices, individual variability, and clinical context all matter.

Statements such as “this red area proves trauma” or “this spot means ADHD” go beyond what the map can establish by itself.

What Should You Ask a qEEG Provider?

Ask how the data are recorded and cleaned, how the map is used in treatment planning, what the provider believes qEEG can and cannot diagnose, and how progress will be measured outside the map.

A responsible answer should include limitations.

qEEG Brain Mapping in Round Rock

Infinite Potential's physical Brain Performance & Optimization Center is in Round Rock, where we provide 19-channel qEEG brain mapping and individualized neurofeedback. Clients also come to us from Austin, Georgetown, Cedar Park, Leander, Pflugerville, Hutto, and surrounding communities.

Frequently Asked Questions

Is qEEG a different machine from EEG?

qEEG begins with EEG recording. The “quantitative” portion refers to mathematical/computational analysis of the EEG data.

Can qEEG replace a psychological or medical evaluation?

No. It should not be treated as a substitute for appropriate clinical assessment.

Does neurofeedback put electricity into my brain?

Standard EEG neurofeedback records scalp activity and provides feedback; the sensors do not deliver electrical stimulation.

Want to Understand the Process Before You Decide?

Contact Infinite Potential to learn more about qEEG brain mapping and neurofeedback at our Round Rock center.

Sources:
Ölçüoğlu R. Neurofeedback for ADHD: Exploring the Role of Quantitative EEG and Brainwave Modulation. 2025. https://pubmed.ncbi.nlm.nih.gov/40760811/
From Aberrant Brainwaves to Altered Plasticity: A Review of QEEG Biomarkers and Neurofeedback in ADHD. 2025. https://pubmed.ncbi.nlm.nih.gov/40940749/

Educational content only. qEEG does not independently diagnose ADHD or other psychiatric conditions.