Forensic memory screening tests are less effective in older adults

New research led by the University of Kent School of Psychology has found that some methods of brain activity used to detect incriminating memories do not work accurately in older adults.

The findings show that evidence of hidden information based on electrical activity of the brain (electroencephalography) [EEG]) are ineffective a older adults due to changes in brain activity related to recognition that occur with aging.

EEG-based forensic memory detection is based on the logic that suspects of guilt will have incriminating knowledge about crimes they have committed and therefore their brain will get a recognition response to the EEG when faced with reminders of their crimes.

The Kent team of researchers led by Dr. Robin Hellerstedt and Dra. Zara Bergström conducted the study with 30 participants under the age of 30 and 30 participants over the age of 65. All participants performed a hidden information test to detect if they recognized details. from a mock crime they had just committed, which would indicate criminal guilt. However, only young adults showed a strong EEG recognition response to crime reminders, with these responses being absent in the older group. This failure to detect memories with EEG brain activity occurred even though the larger group had the same knowledge about the crime as the youngest group, and had the same general recognition memory capacity.

The research published by Cortex therefore, it suggests that EEG-based forensic memory screening tests have been limited practical applications with less validity in older adults than in younger populations.

Dr Bergström said: “Our research shows that EEG-based forensic memory detection at older ages is impaired, even with methods that compensate for potential age differences in frequency, time and location of brain responses.

“Further research is needed to examine the ability of these tests to detect hidden memories of real crimes and whether memory detection in old age is a reflection of permanent changes in brain functioning or is influenced by motivational processes that may vary by situation. The findings could have implications for criminal justice system processes, such as the use of polygraph techniques, which may be vulnerable to similar limitations. ”