Cannabis and Recognition Memory: False Alarms Are Different From Forgetting

Cannabis-related memory changes can involve accepting an unfamiliar word as familiar, not simply failing to remember a word. A naturalistic study of THC/CBD flower products distinguished recognition accuracy, false alarms, response bias, and reaction time.

What the researchers compared

Paulich and colleagues randomly assigned participants to THC-dominant, approximately balanced THC/CBD, or CBD-dominant flower. Participants used their assigned product at home before testing in a mobile laboratory, with another session without preceding cannabis use.

Product assignment was randomized, but consumption was ad libitum. The design therefore combined experimental allocation with naturalistic variability in intake. Product ratio should not be equated with an identical absorbed dose.

The THC-dominant pattern

In the cannabis-use condition, the THC-dominant group showed poorer recognition accuracy, more false alarms, a more liberal response bias, and slower responding. The approximately balanced group did not show a significant recognition-memory deficit in the same way.

That pattern raises a hypothesis about CBD’s modifying role. It does not establish that CBD is a universal antidote. The paper acknowledges mixed findings in prior research, and the result is specific to the studied products, use conditions, and recognition task.

Why this matters for recollection evidence

A false alarm, a missed item, and a slower correct response are different errors or outcomes. Their implications for a disputed account depend on whether the person was encoding information, retaining it, or deciding later whether it was familiar.

The laboratory word-recognition task did not measure a particular witness’s accuracy about a real incident. Nor does the product label prove that the witness experienced the study’s group-level pattern. Actual timing, exposure, questioning conditions, and corroborating evidence remain important.

Boundaries on interpretation

Subjective bodily-sensation ratings did not distinguish the product conditions in the same way as the memory outcomes. Feeling an effect and performing a recognition decision are therefore separate evidence.

An expert should identify the error type and study comparison supporting the opinion, preserve nonsignificant findings, and explain the differences between the research task and the actual memory question. The study supports a more precise inquiry; it does not establish that every cannabis user’s account is unreliable.

For related context, see our discussion of selective findings across cannabis memory tests.

Primary research

Katie N. Paulich; Christian Place; Gregory Giordano; William B. Carpenter; Tim Curran; L. Cinnamon Bidwell. Naturalistic investigation of cannabis strains varying in THC and CBD ratios and verbal recognition memory. Frontiers in Psychology (2026). DOI: 10.3389/fpsyg.2025.1685412.