Introduction

Kim Peek is the inspiration behind the movie Rain Man. Despite multiple types of damage to the brain, he is one of the world's mega-savants due to his exceptional memory.

This short video briefly describes his condition:



Having read about 10 000 books over his lifetime, with the ability to recall most of this information, Kim has garnered international attention for his phenomenal memory capacity. Among other topics, he is extremely well versed in the fields of:

• History
• Sports (professional basketball, football and baseball)
• The Bible
• Movies
• Calendar Calculation
• Telephone area codes and zipcodes

Aside from that, Kim has the astonishing ability to read two pages of a book a the same time. His estimated retention of the material read is 98%. Furthermore, a page that would ordinarily take 3 minutes to read can be scanned and retained by Kim in about 10 seconds.

Peek is an endearing person who, despite having amazing memory capacity, can neither reason out mathematical problems nor understand certain concepts. One example of the latter is - he might be able to tell you about all the wars that occurred in human history, but would not understand the concept that drives their fighting.

This short interview with Richard Quest of CNN further explains Kim's phenomenal abilities.

The following pages will discuss Kim Peek’s extraordinary condition

with emphasis to his unique cognitive ability in the realm of semantic

memory.

Biography

Kim Peek, the inspiration behind the movie Rain Man, was born on the 11th of November 1951.

At birth, doctors discovered that Kim suffered from several major defects to the brain. He was classified as mentally retarded. Later, he was diagnosed with autism. At 9 months of age, Kim’s parents took him to a neurologist. The doctor perused Kim’s case briefly and concluded that Kim was too mentally retarded to walk or learn, and suggested he be put in an institution and forgotten about. Kim’s parents did not oblige.

Kim’s father (and permanent guardian) reports that at 16-20 months, Kim was able to memorize every book that was read to him. Soon, he began reading on his own. After reading a book, he’d place it back on the shelf upside down to signal that he’d already read and memorized that book and he didn’t want to have it read to him again. That habit has stuck with him until the present day – he still returns books to their shelves backwards or upside down.

One pivotal moment in Kim’s development occurred at age 3 – he asked his parents the meaning of the word ‘confidential’. Kim’s parents jokingly told him to look it up in the dictionary, but that’s exactly what the 3-year-old did. Astoundingly, he managed to use alphabetical order to look the word up. The most recent estimation puts the number of books that Kim has read at 10 000, and he has the ability to recall all of them to a large degree of accuracy.

Kim’s motor skills lagged behind other children of his age. For example, he did not walk until he was 4 years old. At the age of 6, a brain surgeon offered Kim’s parents the option of giving Kim a lobotomy so that Kim could be permanently institutionalized. However, they refused and tried to bring Kim up in a way that was as normal as possible.

Anatomy of the Brain

Kim Peek’s brain differs from that of the average person. He was born with:-

Macrocephaly

This is when the circumference of a person’s head is larger than average in comparison to the person’s age and sex.

Damage to the Cerebellum

The cerebellum is the region of the human brain that has been implicated in motor control and sensory perception.

Sensory perception involves acquiring, interpreting, selecting, and organizing information derived from our five senses (sight, sound, taste, touch and smell). Despite the damage to his cerebellum, Kim Peek possesses no difficulties in perceiving sensory information.

Kim does, however, face problems with his motor skills. He cannot button up his shirt, nor can he brush his teeth without help. When he first started to walk (at the developmentally delayed age of 4), he did so in a sidelong manner. Until this day, he needs help from his father (and caretaker) Fran to complete every day self-care tasks.

Encephalocele of the Brain

This is a congenital condition (birth defect) where infants have an excess portion or gap in the brain where there is a protruding sac. The sac can be big or small, located on any part of the skull. It may contain portions of disorganized cerebral matter, or excess spinal fluid.

The prognosis/outcome for patients with encephalocele of the brain range from mild to severe, depending on the size and location of the sac.

Kim Peek’s condition has been grossly been defined as ‘a water blister in the back of his brain’. This defect may contribute to some of his difficulties in completing everyday tasks. This can also explain some of the signs of mental retardation and other developmental delays he displayed as a child.

Agenesis of the Corpus Callosum

The corpus callosum is often referred to as the ‘bridge’ between the two hemispheres of the brain. Simply put, it is a bundle of nerves that connects the left side of the brain to the right, and helps with inter-hemispheric communication.

Agenesis of the corpus callosum is also a rare congenital disorder (birth defect) where there is a partial or complete absence of the corpus callosum. This condition has a myriad of manifestations, including problems with perception, speech and language delays, social difficulties, and even mental retardation.

In the case of Kim Peek, doctors and neurologists have speculated that it is this factor that makes him special – his neurons have somehow made other connections in the absence of the corpus callosum, resulting in a complete bypass of that connective ‘bridge’, leading to increased ‘data storage’ section of the brain with enhanced memory capacity.

Remarkable Memory

Memory can be divided into three subsections, which are sensory, short-term, and long-term memory. In the case of Kim Peek, his sensory and short-term memory seem to function normally. His rise to fame was mostly due to his exceptional long-term memory abilities, namely his talent for remembering every book he has read with high recall and recognition.

Long-term memory can be divided into two categories, procedural memory and declarative memory.

Procedural memory

- Also known as implicit or unconscious memory

Procedural memory, as the name suggests, is the long-term memory for “How To” information such as technical skills and procedures. Governed by different mechanisms than that of declarative memory, procedural memories are typically called upon without us having to think about it.

They are rarely verbalized, and often, people do not remember how, when, or where they picked up that particular procedural skill. Some examples are riding a bike, typing, or swimming. Even if you could not remember who taught you to ride a bike, how old you were when you first typed on a keyboard, or where your first swimming lesson was, you would still be able to perform those procedures.

In the case of Kim Peek, some doctors believe that his procedural memory is impaired. This is because he has problems with some everyday tasks, such as figuring out a light switch, how to button up his shirt, brushing his teeth or combing his hair. He still needs help from his father to complete these ordinary self-care tasks that most of us take for granted.

It is important to note too, however, that doctors also believe that many of his inabilities to complete daily tasks are concurrently attributable to his impairment in motor skills.


Declarative memory

- Also known as explicit memory

Declarative memory is the memory store that deals with facts. These are memories that can be recalled, consciously discussed, and repeated aloud (declared). It is often equated to the concept of knowledge.

There are two types of declarative memory, which are semantic memory, and episodic memory. Episodic memory is theoretical data that incorporates knowledge of a specific time and place – such as personal experiences. Semantic memory is information that is memorized without the need for knowing about a specific event – that is, factual knowledge. Semantic memory includes stored information about things and their meanings, occurrences in history, geography, etc.

In the case of Kim Peek, it is his amazing capacity in semantic memory that shot him to fame. As mentioned in the introduction, he has read upwards of 10 000 books, and is able to retain most of this information with a high degree of accuracy.

Declarative memories can be more solidly committed to memory by using mnemonics (memory aids) and rehearsal or repetition. Information that is not regularly accessed is subject to being forgotten, although those that have been remembered well have the capacity to stay in the memory for indefinite amounts of time.

One interesting difference between Kim Peek and other people is that he does not seem to actively commit the information that he knows to memory – it happens unconsciously and automatically. He does not purposefully use any mnemonics, or consciously repeat information to himself to remember it. Recall of the information he has read seems to be one of Kim’s special talents.

It is speculated that Kim Peek possesses remarkable skill in eidetic (photographic) memory. This is sometimes known as ‘total recall’. It is defined as the capacity to recall objects, sounds, images, events or words from books in abundant volume, with extreme accuracy.

Children and adults who possess such memory have been known to be able to remember nearly-perfect representations of whatever it is they are asked to recall. Eidetikers, as they are known, have claimed to be able to ‘see’ those representations in an extraordinarily detailed and vivid fashion, despite the fact that the occurrence/object they have been asked to recall has come and gone.

Full Length Documentary

The Real Rain Man Documentary

Part 1



Part 2



Part 3



Part 4



Part 5

Glossary

Lobotomy

A lobotomy is a procedure that involves the cutting of connections to or from the prefrontal cortex, or simply destroying them. This procedure was used in the past to treat severe mental illnesses, such as schizophrenia, anxiety disorders, or clinical depression. This procedure is rarely conducted in present day as patients who have had lobotomies in the past have shown that it can result in major personality changes or even mental retardation.

Sensory Memory

Sensory memory occurs when a person is able to retain impressions of sensory information after the original stimulus has come and gone. Stimuli first detected by the five senses are temporarily retained in sensory registers. While these registers have a large capacity for holding unprocessed sensory information, they can only how accurate sensory information for a short span of time. This time frame is understood to be more than 1 second, but no more than 2. Sensory memory is short lived and is performed automatically. Only the most pertinent information is filtered into short-term memory.

Short-term memory

- Also known as primary, working, or active memory.

Short-term memory is the capacity to hold a small amount of information in the mind for a short amount of time, typically 20 seconds. The capacity of short term memory can vary, but it is estimated that it is limited to 7 (give or take 2) elements. This is in stark contrast to long-term memory, which, theoretically, can hold infinite numbers of information for a long time (even permanently).

Information held in the short-term memory is active, highly accessible, yet small. The information held may include:

• Pertinent sensory input
• Items you’ve retrieved from long-term memory
• Information generated from mental processes (reasoning)
• Information you are trying to rehearse and retain in long-term memory
  

Recall

Recall is the act of retrieving information where a question is asked, and a person is required to produce information as accurately as possible. (E.g. short-answer, fill-in questions, essay questions).

Recognition

Recognition is a relatively simpler task whereby a person is required to pick out the correct response to answer a question. (E.g. multiple choice questions, matching questions, fill-in questions with word banks provided.) Typically, people perform better on recognition tasks because there are more prompts in the questions that cue us to find information stored in long-term memory.