GFSU prof helps police bust criminals' 'memory loss' bluff

'Memory loss', the handiest tool that criminals use at the interrogation room to defuse grilling of cops, has been washed and dismissed by a behavioural science expert of Gujarat Forensic Sciences University (GFSU). The expert used a simple test to prove that the subjects were showing signs of 'Pseudo-Dementia', also called fake Dementia. A situation where the subject fakes a psychiatric condition is called malingering. Ravikesh Tripathi, assistant professor of Institute of Behavioral Science, GFSU, developed a neuropsychological test known as NIMHANS Neuropsychological Battery for Elderly (NBBE) to differentiate between real and Pseudo-Dementia.

The test uses a series of questions targeting multiple domains of cognition to check the memory of the subject, Tripathi said. "The problem with those who fake Dementia is that they don't realise that Dementia patients can exhibit a certain type of memory loss (Cognitive Profile). Often, the general people's understanding of 'memory loss' is based on what they might see in the movies," said Tripathi.

So far, the test has been used to call out the fake Dementia exhibited by accused in few cases. However, it has been standardised for mild cognitive impairment and related disorders.

"Once, an undertrial prisoner claimed loss of memory. The person couldn't even remember the crime s/he committed. However, we did a test and found that he was faking," said Tripathi.

He said the subject in question showed excellent episodic memory. "Those who fake Dementia don't realise that its patients show episodic memory loss (specific cognitive deficits). For example, they might forget if they had lunch and might want food again. In this case, the subject had excellent episodic memory. He could recall the events of the day almost until 10 hours. I think the subject did not realise he was giving himself away perhaps because the questions were framed as general inquiries and not a question and answer session," said Tripathi. In this particular case, the subject initially tried to trick the police, "but during the day we would randomly ask questions. He would answer them correctly without even thinking, and thus revealing himself to be pseudo dementia patient," he said.

He further elaborated that pseudo-Dementia cases often report memory problem repeatedly and also recollect when and where memory lapses occurred. Whereas demented patients are often less aware of the extent of their cognitive deficits. "This means the pseudopatients actually remember that they are forgetting something while those who suffer from Dementia do not realise or remember that they have forgotten something," he said. Neuropsychology of dementia has been explored extensively in the last few decades and attention has been shifted to exploring cognitive profile of the preclinical phase (mild cognitive impairment), which can enhance our understanding and enable us to identify early Alzheimer Dementia as well as help us to distinguish it from pseudo-dementia.

"Those who have been on diabetes or cardiovascular medication for long also sometimes show mild cognitive impairment," said Tripathi.