Charting the path to a biologically informed system of mental illnesses
Willa Goodfellow ~ Mar '20
A moonshot exploring the human brain at single-cell resolution
Andrew Neff ~ Mar '20
Written & Illustrated by Andrew Neff
25 minute read
fMRI: New Phrenology?
Is neuroscience bound to keep repeating old mistakes? An article comparing modern brain imaging with phrenological weirdness.
In the early 1800’s, Franz Joseph Gall announced that he had
discovered an objective, biological measure human psychology.
He didn’t.
Two hundred years later,
a brain imaging technology called fMRI is making the same promise.
This time around, are we ready?
Building from the technological advances of Magnetic Resonance Imaging,
scientists discovered a remarkable property of the brain (Ogawa, 1992).
To anyone working at the time,
it looked like we were on the precipice of entering a new world
where the ambiguity of psychological doctrines would be a thing of the past.
The biological correlates of love and despair,
the true nature of psychiatric disease,
the mechanics of how your brain thinks,
finally,
after millenia of hypothesizing about the nature of the mind,
scientists discovered that maybe,
an objective measure of human psychology was within our grasp.
He was wrong,
basically on all counts.
Today, to most,
phrenology is a joke,
wikipedia declares it as a pseudoscience,
and in 2018,
nails were placed in the phrenology coffin when a group of researchers
decided to use modern imaging methods to test Gall’s claims,
and found no support for the theory (Jones, 2018).
But some people think phrenology is not to be scoffed at,
instead,
it’s a cautionary tale on what can go wrong in neuroscience.
It was a time of Napoleonic invasions,
an industrial and financial boom,
victorian tailcoats, canes, top-hats, and
Franz Joseph Gall
Gall considered himself both a physician and a naturalist.
He was a man that displayed a deep curiosity,
an insatiable appetite for knowledge,
and an unmatched collection,
of human skulls.
Phrenology
the idea
Galls big idea was the following:
throughout adolescence,
as the structure of our bones begins to solidify,
any peculiarities in brain anatomy
are reflected in the final form of the skull.
Psychology emerges from brain function,
which is dictated by brain anatomy,
which is reflected in skull shape.
Therefore,
skull shape can provide us with
an objective measure of psychology.
Including the word fMRI in their description,
1,871 research projects are funded by the National Institute of Health.
Almost a billion dollars in annual government expenditures,
and in 2018,
over half a million scientific papers exist on the subject.
Our federal funding agencies and many in the scientific community
have accepted the value of fMRI,
but if this research really is a new manifestation of phrenology,
we’d probably rather our government not spend a billion dollars on it, right?
It’s not,
let’s just get that out there,
fMRI research is not equivalent to what Gall and his followers did.
The research is far more rigorous,
and scientifically supported,
than anything under the umbrella of phrenology.
But doubts remain about the ultimate value of the technique,
and some of the doubts people had about phrenology
might still apply to the way we practice neuroscience today.
If we can understand what went wrong in 19th century Vienna,
and some of the fundamental limitations to fMRI,
we might take a step closer towards a true understanding of the brain.
The Methods
Phrenology
Gall was a social man, and apparently a perceptive one.
Over tea, or after a night at the theater,
Gall would begin to pick up on his companions psychological characteristics,
and at the same time recognize a peculiar cranial anatomy.
Not completely ignorant to basic scientific practice,
or basic principles of fostering credibility
in a mostly-literate scientific and medical community,
Gall then sought to validate these findings in a larger dataset.
If Gall wasn’t performing validations on cranial dimensions
of marble busts in his friends private collection,
he was examining the set of skulls regularly delivered to him
by a range of victorian characters.
Environmental ecologists would provide animal skeletons,
the police chief generously offered those of executed criminals,
and explorers would fetch human remains from their expeditions to exotic lands.
To understand Gall’s methods,
it’s useful to look at a couple examples.
Of the 27 mental faculties that Gall decided define humanity,
9 of them are unique to humans.
Here are a few:
*
Poetry
the phenomenon
Poetry, to Gall,
encompassed all of the written arts.
Of course, this faculty is innate,
and despite what people may have thought,
poetry was not the combination of more fundamental faculties,
but instead a single coherent entity,
driven by a distinct part of the brain.
the skull
“His forehead immediately above the nose,
rose perpendicularly,
then retreated and extended itself much laterally,
as if a portion had been added to each side.”
It’s a bit hard to say,
but if you were a neuroscientist,
you might think he’s describing the bones
overlying the dorsolateral prefrontal cortex.
the discovery
At some point Gall developed a friendship with a poet.
After recognizing his friends curious skull configuration,
along with his poetic abilities,
and being the cautious, skeptical, scientist Gall claimed he was,
he announced his discovery,
but “spoke to [his] hearers with a tone of doubt”,
and decided one example was just not enough for his rigorous threshold.
So courageous, so ethical.
After giving a lecture in Berlin,
a friend invited Gall to see his private collection marble busts.
Thirty, beautifully crafted, statues of the world's most celebrated poets.
After careful inspection,
Gall found, to his great surprise,
that same prominent forehead
with the wings on the temples
in every single one of em.
Even more interesting,
there was a correlation between the skill of the poet,
and the prominence of their forehead.
Believe it, just believe it.
Wit
the phenomenon
Wit is the faculty to
“consider objects from a point of view altogether peculiar,
find relations altogether peculiar,
and present them in a manner altogether peculiar”.
What does peculiar mean?
Well, Gall’s not sure, but he knows it when he sees it,
just look at Wanda Sykes, or Mitch Hedberg.
What Gall is sure about is that
the faculty of wit entails an insatiable urge to ridicule,
either others or oneself,
and it’s a habit is incurable by parental correction.
the skull
“I have found the anterior superior lateral
parts of the forehead
considerably prominent,
in a segment of a sphere”
a location peculiarly similar to
that of poetry.
the proof
In all the cases that Gall observed,
the wittiest of individuals had this same skull shape.
The peculiar twist though,
is that people who wished they were witty,
and harbored resentment against those who were funnier then them,
had a contraction in that very same region.
Believe me, it’s gonna be great, believe me.
Comparative Sagacity
the phenomenon
Roughly, comparative sagacity describes
the ability, or inclination, to use metaphors.
Which is incredibly useful, Gall figured,
because “comparisons, parables,
spread a gentle and beneficent light,
produce the effect of conviction,
and carry along the most clownish multitude.”
Unfortunately, clownishness does not make the cut for Gall’s psychology.
A philosophically minded friend of Galls
is described as being “embarrassed to prove the truth of his assertions rigorously”,
and therefore, in arguments, tended to resort to elaborate metaphors.
This tactic either effectively convinced, or confused his intellectual foe into submission.
skull description
“in the external superior middle part of the frontal bone,
a great lengthened prominence, to which I had not given attention till that moment.
This prominence commenced in the anterior superior middle part of the forehead,
where it was about an inch broad, and contracting itself in the form of a cone,
reached the middle of the forehead, where it touched the organ of educability.”
By today's anatomy maybe overlying
what’s called the dorsal medial prefrontal cortex.
the discovery
After observing his friends argumentation tactics,
Gall decided he should observe others who spoke similarly.
A pair of jesuit preachers,
the renowned father Barhammer,
and several other undescribed individuals
who all spoke in parable.
To Gall’s astonishment,
that same “vaulted conical eminence”
was right there on their forehead.
QED,
this man is on a roll.
The writings Gall left behind are not in line with basic scientific practices,
mostly because he doesn’t provide an explicit account of his methods.
Did he explicitly quantify skull shape in any way,
if so, where did he place the calipers?
and could I see the data please?
How did he evaluate poetic ability, or wit,
was there a psychological attributes survey
he forgot to include in the supplementary material?
Who made these marble busts, and were they accurate?
But he also wasn’t entirely unscientific in his approach.
In studying skulls of those with highly developed poetic capability,
he provided a list of poets he evaluated,
and asked that history check his work.
Not so bad as far as pseudosciences go,
but not quite science.
Gall’s work was about more than just the relationship between the skull and the mind.
They were about the skull and a particular conception of the mind.
Neuroscientists today have a language,
including concepts like executive function, set switching,
loss aversion, prediction error,
declarative and working memory.
But we haven’t always talked about the same brain functions,
or even the same categories of functions.
Carl Jung preferred to divide brain functionality into thinking, feeling, intuiting, and sensing.
Buddhists consider attachment, aversion, and delusion as the three central features of human suffering.
B.F. Skinner would have rather we not speculated about ambiguous brain functions at all,
instead focusing only on behavior.
Personality, behavior, cognition, emotion,
they’re huge fields,
with diverse premises on what constitutes the minds essential features.
And while there has always been disagreement between psychologists
on how we should think about the mind,
for anyone who wants to claim they’ve found the biological basis of psychology,
that have to claim an understanding of what psychology is,
or at least declare the existence of a couple measurable psychological variables,
and Gall had no issues doing so.
*
In his thinking, there were 27 basic faculties.
Qualities like love of offspring, instinct to kill,
vanity, memory for things, memory for words,
sense of musical tones, and more.
A subset of these qualities are uniquely properties of the human mind
Comparative sagacity, metaphysical spirit, humor, poetry,
moral sense, mimicry, religious instinct, and obstinacy.
Why these 27 divisions?
And what makes these 9 so unique?
Psychology
Franz Gall
The answer is, more or less, because Gall said so.
Often, Gall begins a section outlining his intention
to prove the coherent existence of a mental phenomena.
After providing a few tangential historical anecdotes,
Gall spontaneously declares his proof was successful,
despite paying little or no consideration to the point in contention.
When pressed though,
his most definitive statements on the coherence of
a psychological phenomenon
tend to be along the lines of;
everyone knows that’s true,
and
I’ve studied this very thoroughly, and let me tell you, it’s true, believe me.
Gall seems to prefer focusing on the methods,
the skulls, the brains,
while taking the psychology for granted.
fMRI
There is no one “psychology” of fMRI.
Researchers from diverse fields with unique perspectives on the mind
use fMRI to evaluate the brain correlates of different psychological constructs.
But nonetheless, there are some trends that emerge
in all of modern psychology,
and there are some common psychological tasks
that researcher tend to use with subjects in an MRI scanner.
Here are a couple examples.
*
Positive and Negative Emotion
One common experimental task involves
presenting a subject with a set of “emotional pictures” (Lang, 1993).
Some are “positive”,
like a sunset in yosemite,
and some are “negative”,
there seems to be a few brown skinned children
wandering through trash dumps.
Should we assume that people are
“experiencing positive emotions” when they see positive pictures?
Because to me,
I was a bit emotional watching The Shape of Water when that woman
filled her bathroom with water and started getting sexual with that creature,
but not when I was in an MRI looking at a picture of a family of racoons.
Okay I liked that one, but most of the images just aren’t very moving.
The entertainment industry spends huge amounts of time and money
in order to squeeze the tiniest little bit of emotion out of people.
They might not have unambiguous data,
but it does seem that eliciting a sincere emotional response
is a little more challenging that providing a static image for a few seconds
without any history or context.
*
Response Inhibition
In the stroop test,
subjects are asked to indicate the color of the word presented,
and suppress the urge to read the word (Stroop, 1935).
Response inhibition is supposed to measure the suppression of actions
that are no longer appropriate (Verbruggen, 2008).
Like in The Shape of Water,
when that girls neighbor decided to forego his complacent lifestyle
after he didn’t get the job he hoped for,
to help his neighbor and only friend rescue that creature,
only to be betrayed when he finds out
they flooded and did sexual stuff in his wood floored bathroom.
Was that response inhibition?
Inhibiting career goals when it was no longer appropriate to pursue them?
What do you think his Stroop test results would be?
One of the main reasons scientists want
a biological measure of psychology
is because we don’t trust ourselves.
We don’t trust ourselves to fully understand,
or honestly share what we think and feel.
The ability to understand and predictably influence psychology
represents a one of humanity's greatest challenges.
It’s a little bigger than can be resolved in three paragraphs
and an image traced from wikipedia.
One thing that can be said though,
is that we can’t, like Gall,
take our psychology for granted.
We may not trust psychological variables,
but we’re still using them,
and we can’t keep pretending
that they’re not important to think deeply about.
Having an MRI involves
lying horizontal in a cold scanning room,
wearing earplugs and headphones,
lying completely still,
maybe trying to suppress the urge to sleep,
or suppress the urge to clear ones throat or swallow,
looking at a computer monitor that’s so old it looks like
it has fond memories of displaying the AOL dial up screen,
and responding to, often, decades old visual content,
with one of four buttons placed in a subjects hand.
There are plenty of limitations on how “real” the experience can be.
subjects can’t move,
they can’t exist in a setting in which they typically operate,
and they often aren’t performing tasks
that resemble things they do in their ordinary life.
*
Understanding the biological correlates of psychology
is a kind of a chicken and egg problem.
We can’t know the brain substrate of a psychological process
until we’ve accurately defined the psychology.
But we also can’t know that we’ve accurately defined the psychology
until we find a scientific validation of that psychology’s existence,
more or less, the brain substrate.
Half a century after Gall,
the author Fyodor Dostoevsky wrote
“In every man’s memories there are such things as he will reveal not to everyone,
but perhaps only to friends.
There are also such as he will reveal not even to friends,
but only to himself, and that in secret.
Then, finally, there are such as a man is afraid to reveal even to himself,
and every decent man will have accumulated quite a few things of this sort.”
Some report on what scientists report.
We're here for the real thing.
Independent - design heavy - science journalism.
Support us today on Patreon.
Credulity and Neuroscience
Franz Gall's lectures were cinematic events.
After purchasing their ticket,
attendees would find themselves in a candle lit auditorium.
Distributed throughout the room were Gall’s collection of human and animal skulls
alongside wax casts of variously shaped and sized brains.
In the center of it all would be Gall himself,
in surgical gear,
prepared to discuss the functional anatomical specialization of the brain,
as he dissected a corpse.
One observer noted that Gall spoke with such enthusiasm and confidence
that at times, attendees couldn’t help but cheer and applaud.
In duller moments, surrounded by interested onlookers,
Gall would describe the skull in dry technical terms.
He claimed he spoke with “the most judicious reserve”,
and in his writings he constantly reminded the reader
how complex humans are,
and therefore how important it was
to study several examples
before coming to any definitive conclusions.
But dispersed throughout his proclamations of heroic skepticism
were sweeping assertions about psychology and anatomy.
Assertions derived from small, nondescript samples.
“It is therefore no longer permitted to doubt,
that this talent is indicated by the organization,
which I have described.”
Much of Gall’s display of scientific restraint
appeared to be build up to his emotionally charged rhetoric.
In a discussion on the superiority of white europeans,
in not quite as generous a spirit as Jared Diamond’s Guns Germs and Steel,
Gall Remarked
“The history of the human heart,
...
the spirit of wit, the piercing shafts of satire,
all the varieties of eloquence among the ancients and the moderns,
are confined, almost without exception,
to the latitudes of the fig and the grape.”
In the next few paragraphs,
the phrases “fiery passions”, “burning desires”, and “fires of love” figure prominently.
It’s maybe a bit unfair
that Gall has become synonymous with pseudoscience.
He did make some gestures towards the scientific method,
trying to obtain larger sample sizes,
and describing some, but definitely not all of his methods.
But it appears his priorities weren’t discovering the truth
so much as they were asserting that he had discovered the truth.
While Gall considered himself a naturalist, and a physician,
it would perhaps be more accurate to describe him as a performer (Van Whye, 2002).
Science is supposed to be insulated from showmanship,
researchers are supposed to care only about the facts.
However, all but the top scientists have to engage in some marketing
if they want to continue being scientists.
They need to persuade high profile journals to publish their research,
and funding bodies to continue providing resources.
Typically, scientists are selling to scientists,
so hyperbole and emotionally charged rhetoric shouldn’t matter that much.
But then again,
scientists are people too,
people who don’t always have the time,
or capability,
to thoroughly interrogate other scientists claims.
Now, not everyone in Gall’s time was so credulous,
but phrenology, lead by Franz Gall's charge,
successfully persuaded people of all walks of life,
scientists, clinicians, philosophers, government officials and more,
that skull shape is a biomarker for mental faculties.
Maybe, we’re living in an age of greater skepticism,
especially among the scientific community.
But we’re also living in an age of neuromania,
one or two blog posts from these neuroscientists
should be enough to persuade you of this:
According to the scientist and writer neuroskeptic,
“both neuroscientists and the public are subject
to the same misunderstandings when trying to think about the brain”.
To blame, according to the author,
is the timeless human craving for a “hard” science of the mind,
as was evident in Gall and his followers.
Psychology is ambiguous.
Taken alone,
it will never be able to provide us
with definitive answers to the question that matters most.
To whatever scientist finds the answer,
a continuous stream of grant-funding will mean little
compared to the wealth and glory they will have achieved,
and, I guess,
the satisfaction of achieving eternal human happiness.
In the meantime,
whoever claims they've seen hard data
on what it means to live a good life,
might think they're buying themselves credibility.
Or maybe that's not what people are thinking,
but whatever is it that's driving this phenomenon,
perhaps the same force
that drove us to forgo a scientific attitude
in favor of neuro-answers
is still with us in some way.
fMRI is not phrenology.
In 1828, Franz Gall passed away.
As he desired,
and as he deserved,
his body was donated to science,
phrenological science.
His skull was measured,
brain morphology assessed,
and the data generated ended up where it belonged,
in the annals of history, not science.
*
Despite many decidedly pessimistic attitudes towards fMRI,
there is one widespread clinical use.
Neurosurgeons use it in tandem with other techniques
to map out the location of particular brain functions prior to resective surgery.
This is an incredibly important use of fMRI,
and for this reason alone, we can’t abandon it.
But remember why we started doing this,
and look at what the active research is on.
Most of it isn’t about improving outcomes in surgical intervention.
We don’t use fMRI in psychiatric diagnosis,
or psychotherapeutic treatment.
We can’t use fMRI to tell us what career would provide us fulfillment,
to understand whether we should continue
a relationship with a romantic partner,
or how to help our children find meaning and happiness in life.
Maybe it’s the coarse resolution of the technology,
or maybe it’s lack of creativity and applicability of the psychology we’re using.
Franz Gall didn’t improve human psychological welfare,
and fMRI has, at least so far,
not fared much better.
And after three decades of trying,
it makes one wonder whether it’s about time we try something else.
References:
Primary Source
-
Gall, Franz Josef. On the functions of the brain and of each of its parts: With observations on the possibility of determining the instincts, propensities, and talents, or the moral and intellectual dispositions of men and animals, by the configuration of the brain and head. Vol. 1. Marsh, Capen & Lyon, 1835.
Gall
-
Van Wyhe, John. "The authority of human nature: the Schädellehre of Franz Joseph Gall." The British journal for the history of science 35.1 (2002): 17-42.
fMRI
-
Azevedo, Frederico AC, et al. "Equal numbers of neuronal and nonneuronal cells make the human brain an isometrically scaled‐up primate brain." Journal of Comparative Neurology 513.5 (2009): 532-541.
-
Cheng, Yawei, et al. "Love hurts: an fMRI study." Neuroimage 51.2 (2010): 923-929.
-
Copeland, Jack G., et al. "Cardiac replacement with a total artificial heart as a bridge to transplantation." New England Journal of Medicine351.9 (2004): 859-867.
-
DeFelipe, Javier, et al. "Estimation of the number of synapses in the cerebral cortex: methodological considerations." Cerebral Cortex 9.7 (1999): 722-732.
-
Eklund, Anders, Thomas E. Nichols, and Hans Knutsson. "Cluster failure: why fMRI inferences for spatial extent have inflated false-positive rates." Proceedings of the National Academy of Sciences (2016): 201602413.
-
Jones, Oiwi Parker, Fidel Alfaro-Almagro, and Saad Jbabdi. "An empirical, 21st century evaluation of phrenology." bioRxiv (2018): 243089.
-
Lang, Peter J., et al. "Looking at pictures: Affective, facial, visceral, and behavioral reactions." Psychophysiology 30.3 (1993): 261-273.
-
Logothetis, Nikos K., et al. "Neurophysiological investigation of the basis of the fMRI signal." Nature 412.6843 (2001): 150.
-
Lüders, Eileen, Helmuth Steinmetz, and Lutz Jäncke. "Brain size and grey matter volume in the healthy human brain." Neuroreport 13.17 (2002): 2371-2374.
-
Müller, Veronika I., et al. "Altered brain activity in unipolar depression revisited: meta-analyses of neuroimaging studies." JAMA psychiatry 74.1 (2017): 47-55.
-
Papanicolaou, Andrew C., et al. "Clinical Applications of Functional Neuroimaging: Presurgical Functional Mapping." The Oxford Handbook of Functional Brain Imaging in Neuropsychology and Cognitive Neurosciences(2017): 371.
-
Park, Soo Hyun, et al. "Functional subpopulations of neurons in a macaque face patch revealed by single-unit fMRI mapping." Neuron 95.4 (2017): 971-981.
-
Pelletier, Mario, et al. "Separate neural circuits for primary emotions? Brain activity during self-induced sadness and happiness in professional actors." Neuroreport 14.8 (2003): 1111-1116.
-
Rusconi, Elena, and Timothy Mitchener-Nissen. "Prospects of functional magnetic resonance imaging as lie detector." Frontiers in human neuroscience 7 (2013): 594.
-
Schüz, Almut, and Günther Palm. "Density of neurons and synapses in the cerebral cortex of the mouse." Journal of Comparative Neurology 286.4 (1989): 442-455.
-
Stroop, J. Ridley. "Studies of interference in serial verbal reactions." Journal of experimental psychology 18.6 (1935): 643.
-
van Atteveldt, Nienke M., et al. "Media reporting of neuroscience depends on timing, topic and newspaper type." PloS one 9.8 (2014): e104780.
-
Verbruggen, Frederick, and Gordon D. Logan. "Response inhibition in the stop-signal paradigm." Trends in cognitive sciences 12.11 (2008): 418-424.
