Oliver Sacks was a clinical neurologist whose writings on his patients captivated the world.  Sacks wrote with the expressed purpose of highlighting the personalities of his patients so that we may better understand how their conditions impacted their lives and, furthermore, sympathize and connect with them.  Cold and objective research journals and case studies rarely endeavor to invoke a sense of connection and caring for patients.  Oliver Sacks succeeds to this end in leaps and bounds.

I chose to focus on some of his work on hallucinations as, I found them ideal to exemplify Oliver Sacks work in such a brief assignment as this.

One of his many books, Hallucinations takes aim at the misconception that only the mentally insane hallucinate.  Sacks distinguishes types of hallucinations.  Psychological hallucinations are often present in disorders such as schizophrenia and see patients interacting with their hallucinations or vice versa.  These hallucinations may also be guided by their emotional state and similar factors.  Hallucinations associated with Charles Bonnet syndrome, however, present to patients as movies unfolding before them; landscapes, disembodied geometry, faces, or even cartoons may appear.  The key distinction here is that these patients and their hallucinations do not interact.  Charles Bonnet patients often don’t seek help for fear of being labeled as “mad.”  Oliver Sacks set out to prove their sanity (or at least present evidence that does).

fMRI imaging has been used to associate brain regions with certain types of visual perception and visual hallucinations by relative blood flow to those parts of the brain.  The fusiform gyrus, for example is key in facial recognition.  Damage to the fusiform gyrus can cause people to no longer posses facial recognition faculties.  Abnormal activity in the fusiform gyrus, however, can lead to the hallucination of faces.  fMRI imaging has revealed the anterior portion of the fusiform gyrus to be where teeth and eyes are represented.  This is consistent with warped eyes and teeth as a common feature of distorted facial hallucinations.  When patients under fMRI experienced such a hallucination, blood flow to this area increased, showing that it was active.  Similar associations were built during other kinds of hallucinations under fMRI.  A specific area was identified to be active when one sees cartoons, draws, or hallucinates cartoons.  Another was found to be active during recognition or hallucination of buildings or landscapes.  These hard biological representations of hallucination get even more specific with the concept of face cells.  Face cells exist for individual people in our lives; be they family members of celebrities.  Similar cells exist for cars and types of cars, for example.

A lack of visual input to such parts of the brain cause them to become hyper excitable.  They start to fire spontaneously, leading to hallucinations.  This can be due to deficits at the level of the eyes or at visual cortical areas themselves.  Charles Bonnet Syndrome occurs at the level of the inferotemporal cortex; at this level, images are represented by individual neurons, or clusters of them.  These images are the fragments of perception which are assembled by higher order areas of the brain into a cohesive stream of perception.  So, Charles Bonnet hallucinations do not involve the higher order areas associated with memory, personality, etc.  Thus, the will, experiences, and mental state of the afflicted have no bearing on their hallucinations; thus, they cannot influence or interact with them in any way.  They are left with flashes of the chaos of their inferotemporal cortex.  As Oliver Sacks puts it…

“Instead of normal perception you are getting an anarchic, convulsive stimulation, or release, of these visual cells in the inferotemporal cortex”

Sacks goes on in other writings to describe his own experience with hallucinations in the form of ocular migraines.  Migraines can produce a wide variety of hallucinations, or auras.  Auras can be visual, auditory, taste, or even the sense of an ineffable invisible presence.  Visual migraines often produce hallucinations of geometrical patterns that are widely conserved among patient accounts.

Sacks described the work of Heinrich Klüver, who determined that such geometric “form constants” can be elicited by the early stages of mescal, various medical conditions other than migraines, and even the application of pressure to the eyes or the flickering of lights in those without any existing medical condition or psychedelic drug.  Such geometry and other hallucinations, Sacks purports provide interesting insights into the innerworkings of our visual pathways and the delicate nature of our brains.

The way he describes his patients is not from a standpoint of pity, or horror, or warning, or of disgust; he describes them with wonder.

“We may say they are travelers to unimaginable lands-lands of which otherwise we should have no idea or conception.”

He even expresses wonder at his own migraine imagery and even seems to have a sort of fondness for it, believing such conserved patterns to be a shared human experience, and furthermore a natural phenomenon of self organization.  That is, comparing the self organization of our brains to that of falling snowflakes arranging themselves.

These accounts are very important to me and countless others the world over as Oliver Sacks regards what are commonly considered defects -lesser and limited ways of seeing the world- as opportunities to see the world as few else can.  As someone who struggles with ADD, I have adopted the approach of curiosity toward how my brain works, rather than shame. 

Presentation: https://docs.google.com/presentation/d/1pWhum9yp8KyhGvyvuN8CHraNWBSRqNXYEkiJXd5o4bk/edit?usp=sharing