Use case

Chemo Brain Fog — Cognitive Symptoms & Tracking

Cognitive changes during and after chemotherapy — what's known about 'chemo brain,' which tests help you self-track, and what not to expect from a free tool.

What's happening

Cognitive impairment associated with cancer treatment — often called 'chemo brain' or cancer-related cognitive impairment (CRCI) — is recognized by the National Cancer Institute and is reported by a substantial fraction of patients during and after chemotherapy. Commonly affected domains include short-term memory, processing speed, attention, and executive function. The mechanism is multi-factorial: direct effects of some agents, inflammation, hormonal shifts, sleep disruption, and psychological burden all contribute. Symptoms typically improve over months to years for most people; for some, they persist. CogTracker does not diagnose or treat chemo brain — what it does is give you a standardized way to watch your own trend and notice whether lifestyle factors move it.

Sources cited below. This page is informational only and is not a medical diagnosis.

Which CogTracker tests help for chemotherapy (chemo brain)

3 of the 4 cognitive mini-tests are most directly relevant to this pattern. All tests are free.

Working Memory (Digit Span)

Short-term/working-memory changes are among the most frequent patient complaints during chemo; digit span is quick and repeatable.

Run the Working Memory (Digit Span) test

Reaction Speed

Processing-speed slowing is documented. A simple reaction test gives a clean daily signal.

Run the Reaction Speed test

Attention (Stroop)

Attention and executive control are also frequently affected. Stroop probes inhibitory control in about a minute.

Run the Attention (Stroop) test

Track chemo brain fog over time

Start your baseline now

A single score tells you little. Testing 3× a week for 2-4 weeks reveals whether your symptoms track with sleep, caffeine, exercise, or stress. The test battery takes under 2 minutes.

1.Pick a consistent time of day — e.g. 30 minutes after your first coffee.
2.Take the 4 cognitive tests (~45 seconds total).
3.Log today's sleep, caffeine, exercise, stress (~15s).
4.After 5+ sessions, unlock the correlation heatmap showing which factors most affect YOUR score.

Frequently asked questions

Is chemo brain real?

Yes. The National Cancer Institute and major oncology bodies describe it as a recognized and researched phenomenon under the name cancer-related cognitive impairment (CRCI).

Will it get better after I finish treatment?

For many patients cognitive symptoms improve in the months to years after treatment ends. A minority experience longer-lasting changes. CogTracker can help you watch your own recovery trajectory, but it is not a substitute for follow-up with your oncology team.

Should I use this instead of talking to my care team?

No. If cognitive symptoms are affecting daily functioning, your oncology and primary care team should know — they can refer to cognitive rehab, adjust medications that affect cognition, or screen for treatable contributors like anemia, thyroid changes, or depression.

What lifestyle factors matter most?

Research points to sleep, exercise, and managing co-occurring anxiety/depression as factors that consistently affect cognition during treatment. CogTracker lets you see which of these most affects YOUR score after 5+ sessions.

Sources

Medical disclaimer: CogTracker is for self-tracking and informational purposes only. It is not a medical device, diagnosis, or treatment tool. Consult a licensed healthcare provider for cognitive concerns. If in crisis, call or text 988 (US Suicide & Crisis Lifeline) or your local emergency services.

Ready to see your baseline?

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