Hal Blumenfeld, MD, PhD

Expertise: Dr. Hal Blumenfeld is a neurologist and neuroscientist whose expertise focuses on the neural mechanisms underlying normal consciousness, impaired consciousness in epilepsy, and neurostimulation to modulate conscious arousal. His research combines neuroimaging, electrophysiology, behavioral testing, and animal models. The goal is to understand how brain networks contribute to conscious function and how seizures affect these networks. His work also focuses on developing new treatments and advancing clinical approaches for patients with epilepsy and disorders of consciousness.

1. The Neuronal Mechanisms of Consciousness What consciousness is and how it works has been intensely debated for millennia, but it is now accessible to modern tools of neuroscience. Research uses visual, tactile, and auditory perceptual behavioral tasks coupled with pupillometry, fMRI, intracranial EEG, high-density surface EEG, and machine learning to understand where and when the human brain is active during conscious perception. Invasive and non-invasive deep brain stimulation provides additional crucial insights into subcortical modulation of consciousness. This work has important clinical implications, particularly for patients experiencing abnormal conscious states, including epilepsy, other disorders of consciousness, and psychiatric disorders.

2. Impaired Consciousness in Focal Seizures

How do focal seizures impair consciousness? Research examines the mechanisms by which temporal and frontal lobe seizures disrupt consciousness and brain network function. Temporal lobe epilepsy is studied through intracranial EEG, SPECT, high-field fMRI, single-neuron recordings, neurotransmitter studies, and animal models to understand how seizures affect cortical and subcortical arousal systems and to evaluate potential treatments, including deep brain stimulation. Research on frontal lobe seizures examines distinct patterns of brain network activity associated with impaired versus preserved consciousness.

3. Impaired Consciousness in Childhood Absence Epilepsy

Absence seizures are brief episodes of staring and unresponsiveness. Research in the Blumenfeld lab has examined how these seizures affect attention and brain network function in children through simultaneous fMRI and EEG recordings and behavioral attention testing during and outside of seizures. This work has identified abnormal activity in specific brain regions that may provide new targets for treatment. Meanwhile, animal model studies are being used to identify specific neuronal types and networks contributing to impaired consciousness during seizures.

4. Advanced Behavioral Testing and Driving in Epilepsy One of the most devastating effects of altered consciousness in epilepsy is impaired driving safety. Research uses virtual reality driving simulation during video/EEG monitoring to examine how epileptic seizures affect driving performance. Prospective bedside or at-home testing using wearable technology – the ARTiE watch (Automatic Responsiveness Testing in Epilepsy) – provides additional objective measures of responsiveness and awareness during seizures.