Older Minds: How Age Changes the Test for Hidden Truths

The world is getting older, and with that shift comes a new challenge for tools used to spot deception. One such tool is the Concealed Information Test, or CIT, which relies on tiny changes in skin sweat, heartbeats and breathing to show whether someone remembers a crime detail. In Japan, where many people are now seniors, the CIT is a popular tool for police work.

Most research proving the CIT works has been done with young, healthy college students. But when people age, their bodies respond less strongly to stress and surprise. It’s unclear whether the CIT still works well with older adults.

To find out, researchers tested 33 seniors aged 62 to 80. Each participant went through two parts of the CIT: first, they learned a secret fact and then tried to hide it; second, they didn’t know the fact at all. The team recorded skin conductance (how sweaty the skin gets), heart rate, and breathing.

The results were mixed.

• Skin conductance still showed differences between the two parts of the test, but more seniors didn’t show any reaction at all.
• Heart rate changes were hard to interpret with the usual analysis, but when the researchers adjusted for a one‑second lag before the test started, they could spot hidden knowledge.
• Breathing patterns didn’t help at all.

Overall, the study shows that age affects all three measures used in the CIT. Even with tweaks to how the data is analyzed, older adults’ weaker physiological signals make the test less reliable. The findings suggest that investigators should be careful when using the CIT with seniors and that more work is needed to understand how aging changes bodily responses used in lie detection.