confabulatory hypermnesia

Neurophilosophy is all abuzz with the discovery of a new neurological disorder known as confabulatory hypermnesia, also known as severe false memory syndrome. The gist of it is that the one individual they've come across who is afflicted with it exhibits a surprisingly accurate detail of memories he's completely made up. While confabulatory hypermnesia resembles spontaneous confabulation, a disorder characterized by making up accounts that may be fantastical in nature, the defining feature of confabulatory hypermnesia is that this individual provides answers to questions that would normally be answered by both normals and spontaneous confabulators with "I don't know." (*Note: Oliver Sacks had a fantastic account of spontaneous confabulation in The Man Who Mistook HIs Wife for a Hat*)

For example:

3.3.1. Personal Semantic Memory
Q. ‘‘What is your brother’s job?
A. ‘‘Re´my is an artist. He works in variety shows.’’ LM confuses
his brother with his son (Patrik) who actually works as
an artist in variety shows.

3.3.7. Semantic Plans
Q. ‘‘What do you think will be the most important advancements
in the exploration of space in the next 10 years?’’
A. ‘‘We will land on the Moon and see if somebody lived
there, if it is habitable.’’

3.3.10. ‘‘I don’t know’’ Episodic
Q. ‘‘Do you remember what you had for dinner on Tuesday
two weeks ago?’’
R. ‘‘Steak with French fries.’’
Q. ‘‘Do you remember what you were wearing on the first
day of summer in 1979?’’
R. ‘‘A short and a T-shirt.’’
Q. ‘‘Do you remember what you did on March 13, 1985?’’
A. ‘‘We spent the day at the Senart Forest’’ (a place where
LM used to go often with his family).

The curious thing about confabulatory hypermnesia is that there is no discernible organic lesion associated with it. Spontaneous confabulation and amnesia are often products of Wernicke-Korsakoff's Syndrome caused by severe alcoholism. L.M. was an alcoholic and exhibits the typical global tissue atrophy characteristic of alcoholics, but there is no defined lesion that separates the confabulatory hypermnesic from spontaneous confabulators.

The authors, however, propose an extremely interesting theory as to why this comes about. Before I go into it, Dalla Barbara proposed the Memory, Consciousness and Temporality Theory (MCTT), which suggests that the CNS does not just passively receive incoming information from the outside world, but actually has modes for understanding the object being perceived. In consciousness there are two very important modes that are central to understanding the object as it is rendered by the sensorium: Knowing Consciousness (KC - "the mode of addressing the object in order to know it") and Temporal Consciousness (TC - "temporalising the object according to past, present or future structures of temporality"). When consciousness processes the information, the object then has a Uniqueness (its determination) and a Multiplicity (its indetermination). Dalla Barbara and Decaix give an example:

"This pen on the desk is both a pen and the pen. In the first case it is an undetermined pen, something that belongs to the category of ‘‘pens’’, an object that I recognize and use appropriately because I recognize it. On the contrary, in the second case ‘‘the pen’’ is a determined object, is exactly this pen in front of me, the pen I bought yesterday and that I will be using tomorrow. So, the pen reveals a uniqueness and a multiplicity, the multiplicity of being a pen and not a different object of the object in front of me, the uniqueness of being precisely this pen and not another pen."

Visualized, it appears as follows:



What is hypothesized to happen in confabulatory hypermnesia is that TC is cut off from being able to perceive if an item holds a Uniqueness, so that only the KC is able to determine if an object has a Uniqueness. Unfortunately, this makes it so that pretty much any Multiplicity is deemed to be an appropriate memory, therefore memories are often born more out of association than of actuality. "What TC does instead in this condition is to address Multiplicity of the object as Uniqueness, so that the result is that not only unique personal episodes, but also habits or personal semantic information are considered in a personal temporal framework." "Most of his confabulations to ‘I don’t know’’ Episodic questions reflect the retrieval of personal habits or semantic information rather than retrieval of imagined events: the Senart Forest is a place where he used to go often with his family, steak and French fries are a very common meal in France, in summer many people wear shorts and T-shirts."

Visually:



Fantastic stuff, no? It crosses the domains of frontal executive functioning and memory in both episodic and semantic domains, combining them into a real questioning of the nature of our consciousness and our neurological integrity! There are so many questions that these authors suggest that are really burning questions into the study of memory and ultimately the study of how we perceive the world, like what delineates the boundaries of TC, is there a possibility for an episodic and semantic double dissociation in confabulatory hypermnesia, and what are the cognitive and neurological correlates of this disorder?

The fact that we're continuing to unveil new and undiscovered syndromes just goes to show that we are only barely beginning to understand the complexities of the CNS. How I love these uncharted lands!

You can read the paper here.