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Ranmal Samarasignhe, M.D., Ph.D.


Dr. Ranmal Samarasinghe received his MD and PhD degrees from the University of Pittsburgh in 2013. He completed his residency in adult neurology at UCLA in 2017 and then completed an NIH funded post-doctoral research and clinical fellowship at UCLA from 2017-2020. During this period, Dr. Samarasinghe obtained clinical training in epilepsy and neurophysiologic intraoperative monitoring. He also performed research developing stem cell-based models of epilepsy and autism, which is the foundation of his own laboratory.

Dr. Samarasinghe’s laboratory seeks to understand the mechanisms of neural network formation and dysfunction in epilepsy and autism. His efforts are focused on 3D brain-like structures called human brain organoids that are grown in a laboratory dish and that are derived from stem cells. Brain organoids can be generated from the stem cells of individual patients and may provide unique insights into the causes of human neurological diseases such as epilepsy and autism. His laboratory is developing and utilizing multiple methodologies including whole-organoid multiphoton based calcium indicator imaging, voltage sensors, traditional extracellular recordings, high throughput genomic screens, and super-resolution synaptic imaging to interrogate the developmental trajectory of nascent neural networks in organoid models. Dr. Samarasinghe will also continue to manage patients with epilepsy and autism in his clinic and perform neurophysiologic intraoperative monitoring for surgical cases performed at UCLA and affiliated hospitals.

Idan Blank, Ph.D.

Research and Teaching Interests:

I study how we understand language—a phenomenon that is universal across human cultures, yet unique to our species, and allows us to transmit thoughts from one mind to another. What are the component processes of comprehension? What kind of mental structures allow us to “know the meaning” of an utterance? Which distinctions in meaning do these structures make more/less salient? And what mental operations are used to manipulate them?

To understand how comprehension evolves in our minds, I study how it engages our brains: which aspects of comprehension get their own dedicated neural real estate? Which are inseparable, supported by a joint mechanism? And which rely on circuits that serve many domains beyond language? Using neuroimaging (mostly functional MRI), tools from network neuroscience, and a combination of hypothesis- and data-driven approaches, I characterize the functional regions engaged when adult native speakers understand language: their internal organization and relationship to one another (dissociable vs. tightly linked); the division of “mental labor” and the integration of information across them; and the ways they change following brain injuries.

I also use computational methods to evaluate meaning representations that are generated by algorithms trained on natural texts. I examine what knowledge—about words, their combinations, and the underlying concepts—is captured by these representations, and compare it against behavioral benchmarks. I test which features of the linguistic input are minimally required for machines to extract this knowledge.


Idan A. Blank will join UCLA as an Assistant Professor of Psychology in July 2019. He received his PhD (2016) in Cognitive Science from MIT, working with Nancy Kanwisher and Ev Fedorenko, and continued working with Ev as a postdoctoral associate at the McGovern Institute for Brain Research. Prior to that, he studied mathematics, psychology, and theatre arts in the Lautman Interdisciplinary Program at Tel-Aviv University, where he received his MA (2011) working with Galit Yovel.

Idan Blank’s Curriculum Vitae

Representative Publications:

Mineroff, Z.*, Blank, I.A.*, Mahowald, K., & Fedorenko, E. (2018) A robust dissociation among the language, multiple demand, and default mode networks: evidence from inter-region correlations in effect size. Neuropsychologia, 119, 501-511. DOI: 10.1016/j.neuropsychologia.2018.09.011

Blank, I.A., Kiran, S., & Fedorenko, E. (2017). Can neuroimaging help aphasia researchers? Addressing generalizability, variability, and interpretability. Cognitive Neuropsychology, 34(6), 377-393. DOI: 10.1080/02643294.2017.1402756

Blank, I.A. & Fedorenko, E. (2017) Domain-general brain regions do not track linguistic input as closely as language-selective regions. Journal of Neuroscience, 37(41), 9999–10011. DOI: 10.1523/JNEUROSCI.3642-16.2017

Blank, I., Balewski, Z., Mahowald, K. & Fedorenko, E. (2016). Syntactic processing is distributed across the language system. Neuroimage, 127, 307-323. DOI: 10.1016/j.neuroimage.2015.11.069

Blank, I., Kanwisher, N. & Fedorenko, E. (2014). A functional dissociation between language and multiple demand regions revealed in patterns of BOLD fluctuations. Journal of Neurophysiology, 112(5): 1105-1118. DOI: 10.1152/jn.00884.2013

Grand, G.*, Blank, I.A.*, Pereira, F., & Fedorenko, E. (submitted) Semantic projection: recovering human knowledge of multiple, distinct object features from word-embeddings. arXiv:1802.01241