Wilson, Kopelman and Kapur (2008): The Clive Wearing Study

Memory loss and awareness of the past

Memory helps us do more than recall facts: it connects our present experience to our past. Severe amnesia can disrupt this connection, leaving a person confused about time, place or their own experiences. However, complete loss of personal identity is extremely rare. Someone may know who they are while being unable to remember much of their life.

Wilson, Kopelman and Kapur’s 2008 study of Clive Wearing examined an especially severe case. Wearing repeatedly believed that he had only just become conscious, even though he had been talking, making music and writing diary entries. The researchers investigated how neurological damage could produce this striking difference between what he could do and what he believed he had experienced.

Clive Wearing and the aim of the study

Wearing was a highly accomplished musician. In 1985, he contracted herpes simplex viral encephalitis, an infection that causes inflammation of the brain. It left him with extensive brain damage and severe memory difficulties.

He developed both anterograde amnesia, an inability to form new long-term memories, and retrograde amnesia, loss of memories from before the illness. These are different difficulties: one concerns retaining new experiences, while the other concerns retrieving the past.

The study aimed to document Wearing’s neurophysiological assessments and psychological experiences. In other words, the researchers examined both the condition of his brain and how his memory difficulties affected his experience of himself and the world.

How the researchers investigated Wearing

This was a longitudinal single case study: one person was investigated in depth through repeated assessments over 21 years, from 1985 to 2006. It was not an experiment in which researchers deliberately caused or manipulated brain damage.

The sample consisted of Clive Wearing alone. His unusual combination of severe amnesia and retained abilities made his case valuable for understanding memory, but also limited how far the findings could apply to other people.

The researchers combined several kinds of evidence:

• Neuropsychological tests, including IQ tests, verbal-fluency tasks and digit-span tasks, assessed cognitive abilities. Digit span involves remembering a sequence of digits and helps assess short-term memory.
• Memory assessments examined recall of facts and personal events, including delayed recall to test long-term retention.
• MRI scans examined the location and extent of brain damage.
• Observations, interviews and diary entries, alongside accounts from his wife, provided information about everyday behaviour and his beliefs about consciousness.

Test scores supplied quantitative evidence, while descriptions of his behaviour and experiences supplied qualitative evidence. Using both allowed the researchers to compare performance on assessments with life outside the testing situation.

An MRI scan from 1991 was compared with a second, 3-Tesla MRI scan in January 2006. Allowing for improvements in imaging technology, there was very little change. The later scan showed extensive damage to the temporal cortices, greater on the left than on the right. Damage also affected hippocampal and limbic regions important for memory.

What Wearing lost—and what he retained

Wearing consistently scored zero on tests of delayed recall and could not lay down new semantic information. He could briefly hold information in short-term memory, but could not successfully transfer it into lasting long-term memories.

His memory for the past was also severely affected. He had lost most of his episodic memory for the 45 years before his illness: memories of particular experiences in his own life.

Some semantic memory, or factual knowledge, remained. He knew who he was, that he was a well-known musician, where he had attended school and studied music, and that he was married. However, the details were patchy. His memory loss was therefore extensive, but not a complete loss of identity or knowledge.

He also retained the ability to talk, read, write, conduct and sight-read music. His preserved musical skills show that remembering how to perform a learned activity can survive even when remembering particular experiences is severely impaired. This is an important contrast between procedural memory for skills and episodic memory for events.

Assessments found reduced verbal and performance IQ compared with his earlier abilities. Across the 21 years, his memory functioning remained largely unchanged.

Why did he believe he had just become conscious?

For many years, Wearing did not appear to accept that he had a memory disorder. Instead, he explained his missing memories by saying that he had not been conscious since becoming ill.

When shown his diaries, he recognised the handwriting as his own, but said: ‘But I wasn’t conscious when I wrote that, I’m now conscious for the first time.’ His ability to write an entry and his later awareness of having written it were therefore very different.

The researchers considered three interpretations.

A delusion: his repeated, strongly held belief that he had just regained consciousness could be interpreted as a false belief resistant to contrary evidence. Wilson and colleagues had suggested this possibility in 1995. However, he did not report other psychiatric features associated with delusions, so the belief might instead have been his attempt to explain why he could not remember anything.

Loss of autobiographical consciousness: Wearing retained core consciousness—awareness of the present, supported by brief short-term memory. But severe memory impairment prevented him from linking the present to a remembered personal past. The researchers suggested that the severity and extent of his temporal-lobe damage helped explain his failure to recognise that he had previously been conscious. This does not mean he was actually unconscious while talking or playing music.

A coping strategy: believing that he had just become conscious might have helped him make sense of the repeated breaks in his experience. Rather than experiencing his situation as unexplained memory failure, he could explain the absence of memories as a lack of previous consciousness. This was a possible psychological interpretation, not a proven deliberate choice.

Conclusions and the link to the Multi-store Model

The study demonstrates an interaction between biology and cognition. Viral encephalitis can cause serious neurological damage, and damage to hippocampal and limbic regions can profoundly affect memory, everyday behaviour and social interactions.

Wearing’s brief short-term memory alongside his inability to establish new long-term memories supports the Multi-store Model’s distinction between STM and LTM. The two did not function equally well after his illness.

However, the pattern also shows why it is insufficient to treat long-term memory as one undifferentiated store. Wearing retained musical skills and some factual knowledge while losing most personal-event memories. Different aspects of long-term memory can be affected differently.

Evaluating the evidence

Depth is a strength. Repeated tests, brain imaging and everyday observations provided a detailed picture that a brief assessment could not. The long follow-up established that his difficulties persisted rather than being a temporary response to illness. Agreement between different kinds of evidence strengthens confidence in the overall account.

Generalisability is limited. Wearing was one unusually accomplished musician with exceptionally severe brain damage. Other people with amnesia may have different injuries and patterns of preserved memory. His case reveals what can happen, not what must happen to everyone.

Precise localisation is difficult. Several brain regions were damaged, so the researchers could not confidently attribute each difficulty to one area. This was not a controlled experiment, and the findings do not isolate a single cause of each behaviour.

Ethical issues require care. Severe memory impairment raises questions about whether a participant can understand and retain information needed for informed consent. Repeated assessments could also cause fatigue or distress. These are potential concerns requiring safeguards, rather than evidence that the researchers necessarily behaved unethically.

Overall, the study provides powerful evidence that neurological damage can selectively disrupt memory and awareness of the past. Its detailed findings are valuable, but conclusions about all people with amnesia or the exact role of an individual brain region must remain cautious.