Life of James Holman
Synesthesia
LSD
Rewiring
Mixed Bag
100
What blind explorer traveled more than 250,000 miles using a metal‑tipped hickory cane to navigate by sound?
James Holman
“Altogether Holman and his naval jacket, straw hat, and cane traveled 250,000 miles”
100
What is synesthesia?
One sensory input leads to multiple outputs
“For people with synesthesia, one sensory input leads to multiple outputs”
100
What Swiss chemist accidentally discovered LSD in 1943 after experiencing wooziness and streaks of color during a synthesis involving fungus‑derived compounds?
Albert Hofmann
“In 1938 Albert Hofmann’s drug company was searching for new stimulants… on a Friday afternoon in April 1943, he whipped up a fresh batch of one chemical, called lysergic acid diethylamide”
100
Behm’s “vision substitution” device consisted of a camera strapped to his forehead wired to an electrode placed where?
His tongue
“Behm was supposed to use the tongue image to interact with the world around him.”
100
What is this image used to test for?
Color-letter synesthesia
"Normal people find it nearly impossible to pick out the 2s without hunting one by one. To synesthetes, each 2 pops out in Technicolor, instantly."
200
What condition caused Holman’s blindness when “mere sunlight felt like needles piercing his retinas,” eventually killing segments of his optic nerves?
Optic Nerve Damage
“Segments of his optic nerves finally died when he was twenty-five, severing that connection to the brain and leaving him permanently sightless.”
200
If someone heard a siren song when looking at a screen saver of moving dots, what type of synesthesia do they have?
Hearing-motion
“Hearing-motion synesthetes might hear a siren song emerging from a simple screen saver of moving dots”
200
What nickname was given to April 19, 1943, the day Albert Hofmann intentionally ingested LSD and rode his bicycle home during the drug’s first documented self‑experiment?
Bicycle day
“So he tested his guess on Monday, April 19—forevermore known as Bicycle Day…. Feeling unsettled, he asked his assistant to escort him home on his bicycle. It was quite a trip.”
200
What part of the brain was activated when patients used tactile sensations to “see” the world around them?
Vision centers
“The scans revealed that, even though the video information came streaming in through the tongue, the brain’s vision centers crackled with activity”
200
What were the last words Hofmann wrote in his lab journal the day he intentionally ingested LSD?
“Desire to laugh”
“By five o’clock his handwriting had deteriorated into a scrawl. His last words were ‘desire to laugh.’”
300
What scientific institution elected Holman as a member after he conducted research on seed dispersal among islands?
The Royal Society
“Along the way he earned a reputation as quite a ladies’ man, and he did good enough scientific work (on the drifting of seeds among islands) to get elected to the Royal Society and cited by Charles Darwin.”
300
What theory of synesthesia blames poor pruning of neurons during childhood?
Anatomical Theory
“The anatomical theory blames poor pruning of neurons during childhood”
300
What neurological phenomenon did Hofmann experience when “every acoustic perception… became transformed into optical perceptions,” causing sounds to generate vivid images?
Synesthesia
“Every acoustic perception, such as the sound of a door handle or a passing automobile, became transformed into optical perceptions… Every sound generated a vividly changing image”
300
What happened to Pedro that caused him to have to go through a rehab regimen that started with him crawling like an infant?
A stroke
“Pedro suffered a massive stroke in 1959 and was left half paralyzed and speechless”
300
What did Cajal discover about peripheral nerves (which explains why surgeons can reattach severed appendages and get them working again)?
They can regenerate themselves
“He found that peripheral nerves could often regenerate themselves”
400
What writing device, consisting of a wooden slab with wires spaced half an inch apart, did Holman use to guide his hand while composing his travel manuscripts?
Noctograph
“ To record his observations, he used an inkless dictation machine called a Noctograph, a wooden slab with wires strung every half inch to guide his hand across the paper.”
400
What demographic of people “probably experience synesthesia all the time”?
Young children
“As a result, young children probably experience synesthesia all the time."
400
What aspect of neural communication does LSD temporarily disrupt, altering how signals flow between circuits without changing the brain’s anatomical wiring?
Neurotransmitter signaling
“LSD can interfere with neurotransmitters, however, and warp the information flowing through those circuits for a few hours.”
400
What did Cajal believe about nervous pathways in the adult brain that has since been proved wrong, partly due to Bach-y-Rita’s sensory substitution devices?
They are fixed and immutable
“This led Cajal to make the bleak declaration that ‘in the adult brain, nervous pathways are fixed and immutable. Everything may die, nothing may be regenerated.’”
400
Kean compares a wagon wheel carving a rut into the road after repeated journeys to what carving ruts into the brain?
Repeated neuron firings
“Overall, just as a wagon will carve a rut into the road after repeated journeys, repeated neuron firings will carve ruts into the brain that make signals much more likely to follow some neural tracts than others.”
500
What sensory technique, also used by bats, did Holman master by clicking his cane and interpreting the returning echoes to map his surroundings?
Echolocation
“Mastering this sensory capacity—called echolocation, the same sense that bats use—took years of determined work.”
500
Why are color-sound and color-letter the most common types of synesthesia?
Brain geography (The brain regions are close to each other)
“Color-sound and color-letter syneshesia are the most common types because of brain geography: some of the regions that analyze sounds, letters, and colors lie right near each other, so signals can easier leak across the border”
500
What theory of synesthesia, which proposes that the condition arises from failures in inhibitory neural control, does LSD support?
The functional theory of synesthesia
“Perhaps, then, the brains of synesthetes fail to inhibit these underground channels, and information leaks from one brain region to another.”
500
If it doesn’t matter what sensory system sends our brain signals, what then deciphers incoming signals and conjures up perceptions?
Neuron circuits
“It’s really our neuron circuits, not our sensory equipment, that decipher incoming signals and conjure up perceptions”
500
Kean suggests that you can think about gray matter as “a patchwork of chips that analyze different types of information.” Within this same analogy, how does he suggest you think about white matter?
As cables (that transmit information between the chips)
“In sum, you can think about the gray matter as a patchwork of chips that analyze different types of information, and about the white matter as cables that transmit information between those chips.”