Seven readings, eleven cases, and no two readings alike. An argument the field has not settled
and this session will not settle either.
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How this session works
You will write down a definition in the next two minutes,
before you see anyone else's.
We will then run four cases at it. At least one will probably give it
trouble.
Only then do we look at seven readings of the question, and at what the
field has actually published about itself.
You leave with a better defended position, not a correct
one. There is no answer slide.
The one rule
Attacking someone else's definition is easy and cheap. The useful move is naming what
your own definition has to throw out, and saying whether you can live with it.
Do this now, before the next slide
Write one sentence: what makes something neuroengineering rather than
neuroscience, biomedical engineering, or computer engineering?
Keep it. You will be asked to revise it at the end, and the revision is
the point of the session.
2 minutes · silent · no phones
The two answers that usually come first
Applied neuroscience
Neuroscience discovers, engineering applies the findings.
Engineering for neuroscience problems
Engineering principles brought to bear on questions about the nervous system.
Show of hands. Is what you wrote a version of one of these?
Both are defensible. Both are about to have a hard four minutes.
Case 1 of 4
The cochlear implant
1960s to 1980s
Pursued over the objections of prominent auditory scientists who had principled reasons to
believe crude electrical stimulation could never carry speech. It went on to give useful hearing
to hundreds of thousands of people.
Does your definition let it in? If
neuroengineering is applying neuroscience findings, which findings was it applying?
The honest complication: it did apply established tonotopy. What it defied was the view
that fine temporal coding was required. So it applied the neuroscience that was right and ignored
the part that was wrong, which you can only tell apart afterward.
Case 2 of 4
The voltage clamp
1940s instrument, behind Hodgkin-Huxley
The Hodgkin-Huxley equations of 1952 rest on measurements only the voltage clamp could make.
The pattern repeats: single-channel recording did not exist until the patch clamp in 1976, and
human functional imaging went from a few PET centers to a mass activity once BOLD contrast,
described in 1990, removed the need for a radiotracer.
The instrument came first. If
engineering only applies what neuroscience discovers, why are so many landmark contributions to
neuroscience instruments?
Case 3 of 4
A neuromorphic accelerator
event camera for robot vision, never touches tissue
Takes organizing principles from nervous systems and applies them to computation. Published in
the field's journals, taught in its departments. No nervous system anywhere near it.
The arrow runs backwards. If your
definition is about serving the nervous system, this is out, and you have excluded a chunk of the
field's own literature.
Case 4 of 4
Neuromarketing and neuroarchitecture
Both deploy real neuroscience toward practical ends: one to advertising, one to building
design. Both have their own literature, conferences, and practitioners.
Few would call either one
neuroengineering. But if "applying neuroscience to a practical end" is your criterion, on
what grounds do you keep them out and the chip in?
The trap closing
On that criterion, whatever admits the chip admits the ad agency. Same move, same direction,
different destination.
Throws out the cochlear implant, the
voltage clamp, and DBS. The founding achievements.
Read it broadly
"Neural principles applied toward any end."
Lets in neuromarketing, neurolaw,
neuroeconomics, and neuroarchitecture. Stops naming a field.
No setting of this dial keeps the founding cases and excludes the
ad agency. The readings that manage it do something else entirely, which is the next slide.
The problem is not any single case. It is one phrase carrying two incompatible meanings and
borrowing whichever one survives the challenge.
Seven readings, built for argument
Not a survey of what practitioners believe. Constructed to span the
space of defensible answers, then checked against the published record.
1Applied, broad
Any use of neural principles, whatever gets built.
2Applied, narrow
Neuroscience findings applied to a biological or clinical end.
3Methods for science
Engineering built to answer questions about the nervous system.
4Interface discipline
Building the link between a device and a nervous system.
5Clinical
Restoring, replacing, or augmenting function in a living organism.
6Constraint
Engineering where a living nervous system sets the requirements. Take it away and the
design changes or makes no sense.
7Institutional
Whatever the field's journals and departments treat as their own.
Yours
Which of these is your slide-3 sentence closest to?
The four cases, now scored
Same cases, same order, positions now named. Read it as how seven
readings split, not as an answer key.
Case
1 Applied broad
2 Applied narrow
3 Methods
4 Interface
5 Clinical
6 Constraint
7 Instit.
Cochlear implant
ARG
OUT
OUT
IN
IN
IN
IN
The voltage clamp
OUT
OUT
IN
ARG
OUT
IN
ARG
Neuromorphic accelerator
IN
OUT
OUT
OUT
OUT
OUT
IN
Neuromarketing study
IN
OUT
OUT
OUT
OUT
OUT
OUT
Neuroarchitecture
IN
OUT
OUT
OUT
ARG
OUT
ARG
Column 1 keeps the accelerator, and pays for it by keeping the ad agency. Column 7 keeps the
accelerator without the ad agency, but only by deferring to what journals publish.
Eleven cases, seven positions, no two alike
No two positions agree across the table. On four cases, no reading commands more than three of
seven votes.
2 / 3 / 2Voltage clamp
1 / 3 / 3Grid-cell model
1 / 3 / 3EEG headband
3 / 2 / 2EPI sequence
in / out / arguable, out of seven
Live matrix
The reading page has all eleven as an interactive
table. Click a cell for the reasoning, or add your own column and see which position your
calls track.
What the field says about itself
Its own answer is a conjunction
An emerging interdisciplinary research area that brings to bear neuroscience and engineering
methods "to analyze neurological function as well as to design solutions to problems associated
with neurological limitations and dysfunction."
Editorial board definition, in Durand, "What is Neural Engineering?", J. Neural Eng.
4(4) E01, 2007
Position 3 and Position 5, joined by an "as well as", with nothing said about
how the two relate.
Then it hands the question back: the scope is "best determined by the scientists and engineers
that practice it." Position 7, from the document stating the official definition.
And the record contradicts itself
The standard definition
Neuroengineering is a discipline within biomedical engineering using
engineering techniques to understand, repair, replace, enhance, or otherwise exploit
neural systems.
The founding conference
The first IEEE EMBS Neural Engineering conference, Capri, March 2003, was convened as a
gathering for a field distinct from both neuroscience and biomedical
engineering.
Both statements are in circulation. Neither has displaced the other.
Meanwhile the flagship journal's scope claims neuromorphic engineering, computational and systems
neuroscience, and neuroimaging, wider than its own official definition covers.
What few would dispute
The definitions differ. These constraints are largely common
ground.
The target pushes back
Encapsulation begins in days. Day 400 is not the population you recorded on day 1.
The controller is learning too
The decoder adapts to the user while the user adapts to the decoder.
Observability is rationed
No non-invasive way to watch one human neuron. No budget buys out of the trade.
Harm is often irreversible
One skull, one cochlea, one cord. The failure mode is not a product return.
The spec is often unknown
Nobody hands you the correct neural code. You co-discover it while building.
Timelines outrun careers
Cochlear implants: 1960s trials, mid-1980s approval. DBS: 1987 to 1997.
Why any of this matters
A definition is not decoration. Four things actually turn on it:
Curriculum. If neuroimaging is diagnostics and your
definition is clinical, does it belong in the core?
Study section scope. Whether a proposal is reviewed by
people who recognize the work, or by people who think it belongs somewhere else.
Hiring and promotion. Whether a candidate building
neuromorphic hardware counts as a hire in the field or a hire adjacent to it.
What a student is told they are becoming. Arguably the
one that matters most, and reliably the one discussed least.
Break out · 15 minutes · groups of three or four
Pick one and argue it
Which case embarrasses your position most, and can you accept that
exclusion?
An accelerator and a prosthesis front end may share most of their circuit design. Should a
definition separate them?
Every position here excludes something the field's own institutions embrace. Defect in the
definitions, or in the institutions?
Should a definition exclude bad work, or only misplaced
work?
Does the field need a definition at all?
Close
Take out what you wrote at the start. What would you change, and which case
made you change it?
If nothing changed, say which case you are willing to exclude to keep it. Either answer is a
result. "It depends" is not.