David Fischer, MD

fMRI Data Analyst University Overview The University of Pennsylvania, the largest private employer in Philadelphia, is a world-renowned leader in education, research, and innovation. This historic, Ivy League school co...

Regardless, we are excited to see where this road takes us in treating this vulnerable patient population. If you're interested in joining this collaborative effort (@gkaguirre.bsky.social), check out our job posting here!:
wd1.myworkdaysite.com/en-US/recrui...

Neural decoding as a covert consciousness assessment is not without limitations. One cannot investigate another's consciousness without eventually falling into a philosophical rabbit hole. Read a thoughtful editorial about this piece here:
www.neurology.org/doi/10.1212/...

If feasible, the implications are numerous: A more granular tool that identifies a spectrum of covert consciousness. A more sensitive consciousness assessment that circumvents atypical functional neuroanatomy and limited interactivity. And potentially, a brain-computer interface.

It would also allow us to evaluate consciousness not as an oversimplistic dichotomy, but as a continuous spectrum, based on the complexity of distinctions that can be decoded from the patient's brain activity.

Neural decoding for covert consciousness is, in a sense, simpler than what's been done in healthy individuals. We don't need to reconstruct entire narratives (yet). We only need a paradigm to determine if patients can make basic semantic distinctions -- i.e., extract meaning.

What if we used mind-reading to determine what minds were there in the first place? Neural decoding could solve a lot of problems. Unlike behavioral or traditional covert consciousness paradigms, it wouldn't require interaction or assumptions of functional neuroanatomy.

The narratives didn't need to be auditory. The algorithms could even decode narratives from muted movies. This is as close to mind-reading as we've ever come.

Semantic reconstruction of continuous language from non-invasive brain recordings - Nature Neuroscience Tang et al. show that continuous language can be decoded from functional MRI recordings to recover the meaning of perceived and imagined speech stimuli and silent videos and that this language decodin...

Take this brilliant study by @alexanderhuth.bsky.social and colleagues. Healthy subjects listened to narratives during an fMRI scan, then individualized algorithms decoded novel narratives with surprising accuracy.

www.nature.com/articles/s41...

Neural decoding works like this: You train an algorithm to associate stimuli with patterns of brain activity, then use it to "decode" a person's experience from their brain activity. The stimulus can even be a semantic concept, so you can decode not only sensation, but *meaning*.

Thus, current fMRI covert consciousness paradigms may be neither sensitive nor specific. EEG-based paradigms solve some problems, but create others. We therefore may be making errors in who we consider conscious. Enter "neural decoding".

Conversely, what if there is distortion of the brain due to a lesion, and activity occurs outside of typical motor regions? Should we not count this (and risk overlooking consciousness patients)?

Many fMRI paradigms work like this: During a scan, we present alternating periods of commands (e.g., "move your hand") and rest. If there is activity in motor regions during commands (relative to rest), we conclude covert consciousness. But should we? Does slight overlap count?

Reconstructing Covert Consciousness | Neurology Determining the level of consciousness in patients with brain injury—and more fundamentally, establishing what they can experience—is ethically and clinically impactful. Patient behaviors may unreliab...

Covert consciousness, where unresponsive patients willfully modulate brain activity to command, is gaining attention. But these assessments are fundamentally limited. What if we could just... read their minds instead? 🧵 about our paper in
@greenjournal.bsky.social
www.neurology.org/doi/10.1212/...

I'm looking for a research specialist with experience in fMRI analysis to help with a project studying covert consciousness in unresponsive patients, in collaboration with @gkaguirre.bsky.social. Please message me or email me at David.Fischer@pennmedicine.upenn.edu if interested!