Huberman Lab
Dr. E.J. Chichilnisky: How the Brain Works, Curing Blindness & How to Navigate a Career Path
Mon Mar 18 2024visual perceptionretinaganglion cellsretinal implantsneuroengineeringplasticity of the brainself-discoveryintuitionnervous system
Description
This episode explores the fascinating world of visual perception, focusing on the retina's structure and function, retinal ganglion cells, experimental techniques for studying the retina, advanced technology for retinal studies, identifying cell types in the retina, retinal responses to visual stimuli, new discoveries and vision restoration, advancements in retinal implants, enhancing vision and brain function, neuroengineering and responsible development, plasticity of the brain and neural implants, neural plasticity and engineering approaches, personal journey and self-discovery, intuition, self-love, and purpose, recognizing ease and beauty, and the nervous system's role in human experience.
Insights
Understanding Visual Perception
Dr. E.J. Chicholnisky is a leading researcher in understanding visual perception and designing neural prostheses.
Retinal Ganglion Cells
The retina has about 20 different types of ganglion cells, each picking out specific information such as spatial detail, movement, and color.
Advancements in Retinal Implants
Efforts are being made to develop advanced retinal implants that can recognize distinct cell types, stimulate them separately, and create a more natural visual experience by respecting the circuitry of the retina.
Neuroengineering and Responsible Development
Neuroengineering tools are being developed to stimulate specific cell types in the retina to mimic normal patterns of activation and potentially enhance vision capabilities.
Plasticity of the Brain and Neural Implants
Impressive advancements in technology are enabling paralyzed individuals to communicate and interact with devices using their thoughts.
Personal Journey and Self-Discovery
The guest discusses their journey of exploring different paths before settling on neuroscience.
Intuition, Self-Love, and Purpose
The speaker emphasizes the importance of knowing oneself, being oneself, and loving oneself.
Recognizing Ease and Beauty
The feeling of ease is significant in finding one's path and can be observed in body language.
The Nervous System and Human Experience
The podcast guest discussed the advancements in understanding the nervous system and how it can lead to treating human diseases and expanding human experiences.
Chapters
- Understanding Visual Perception and Neural Prostheses
- The Retina: Structure and Function
- Retinal Ganglion Cells and Visual Processing
- Experimental Techniques for Studying the Retina
- Advanced Technology for Retinal Studies
- Identifying Cell Types in the Retina
- Retinal Responses to Visual Stimuli
- New Discoveries and Vision Restoration
- Advancements in Retinal Implants
- Enhancing Vision and Brain Function
- Neuroengineering and Responsible Development
- Plasticity of the Brain and Neural Implants
- Neural Plasticity and Engineering Approaches
- Personal Journey and Self-Discovery
- Intuition, Self-Love, and Purpose
- Recognizing Ease and Beauty
- The Nervous System and Human Experience
Summary
Transcript
Understanding Visual Perception and Neural Prostheses
00:00 - 06:39
- Dr. E.J. Chicholnisky is a leading researcher in understanding visual perception and designing neural prostheses.
- The discussion delves into how neurons encode the world around us to create visual images and how this knowledge can be applied to develop robotic AI devices for enhancing memory and cognition.
- Dr. Chicholnisky's unconventional path into science, including taking time off to dance, helped him determine his professional direction in neuroscience and medicine.
The Retina: Structure and Function
06:11 - 14:12
- Vision is initiated in the retina of the eye where light is transformed into electrical signals and processed before being sent to the brain.
- The focus on studying the retina is driven by the possibility of fully understanding and potentially restoring its function through engineering.
- The retina consists of three layers of cells - photoreceptor cells, a processing layer, and retinal ganglion cells responsible for transmitting visual signals to the brain.
Retinal Ganglion Cells and Visual Processing
13:56 - 21:23
- Retinal ganglion cells in humans extract different features from the visual scene and send them to the brain.
- The retina has about 20 different types of ganglion cells, each picking out specific information such as spatial detail, movement, and color.
- The brain combines the different representations of the visual world sent by the retina to create a cohesive sense of vision.
- The process of how the retina works is an example of how sensory systems function in capturing physical features from the external world.
- Humans heavily rely on vision compared to other species like rodents who use smell and whiskers for navigation and object recognition.
- Human vision differs from some animal species due to variations in photoreceptor capabilities, such as mantises detecting subtle color differences we are blind to.
Experimental Techniques for Studying the Retina
21:04 - 28:05
- Researchers conduct experiments on human retinas obtained shortly after death to study retinal ganglion cells' electrical activity.
- Organ donation centers provide human retinas for research purposes, contributing to both saving lives and promoting scientific understanding.
- Experiments involve intricate processes of retrieving the eyes, keeping them alive, and conducting detailed electrophysiological recordings on the retina tissue.
Advanced Technology for Retinal Studies
27:36 - 34:33
- This podcast snippet discusses advanced technology used to study electrical signals in the retina.
- The technology allows for recording and manipulating electrical signals from retinal ganglion cells, even in a deceased patient.
- By keeping the retina alive and using electrodes, researchers can study how the retina works and potentially restore vision through electrical stimulation.
- Retinal ganglion cells play a crucial role in processing visual information, with about 20 different types covering the entire retina.
- Understanding cell types is essential for studying brain circuits and consciousness, as each cell type has distinct characteristics and functions.
Identifying Cell Types in the Retina
34:03 - 41:25
- Understanding different cell types in the retina is crucial for studying retinal signals.
- Cell types are identified based on their function and electrical properties.
- Using technology like the 512 electrode array allows for simultaneous recording of multiple cells to differentiate between cell types.
- Visual stimuli tailored to known cell responses help in determining cell types' electrical signals.
- An unbiased flickering checkerboard pattern is used to efficiently sample many cells simultaneously during experiments.
Retinal Responses to Visual Stimuli
41:03 - 47:53
- Cells in the retina respond to transitions in the visual scene rather than static images.
- Studying how the retina responds to naturalistic visual stimuli is a growing area of research.
- There are about 20 different cell types in the retina, with limited understanding of their roles.
- The retina is a highly evolved organ with signals likely serving important functions for visual behavior and well-being.
- Research aims to understand the various cell types in the retina and their responses to different aspects of life.
New Discoveries and Vision Restoration
47:28 - 54:49
- Newly discovered cell types in the retina have unique and puzzling properties, such as responding to multiple blobs of light and having spidery-shaped visual response profiles.
- Understanding the signals sent from the retina to the brain can lead to vision restoration techniques by targeting simpler cell types that constitute a majority of neurons transmitting visual information.
- Neuroengineering applications based on understanding retinal signals include potential vision restoration for the blind and enhancing human function beyond natural capabilities, like improved color vision or pattern recognition.
- Electronic implants connecting directly to retinal ganglion cells can potentially replace damaged photoreceptor cells and restore vision by capturing light, processing visual information, and stimulating ganglion cells to send signals to the brain.
- Some individuals who were once blind have experienced visual sensations through implanted electrodes on the retina, enabling them to perceive crude blobs and flashes of light for basic navigation.
Advancements in Retinal Implants
54:24 - 1:01:36
- Current retinal implants are limited in providing high-quality vision due to their simplistic design treating the retina as a grid of pictures, lacking the complexity of different cell types and their specific functions.
- Efforts are being made to develop advanced retinal implants that can recognize distinct cell types, stimulate them separately, and create a more natural visual experience by respecting the circuitry of the retina.
- The goal is to restore vision using science-based approaches that consider the intricate signaling patterns of the retina, which have not been fully incorporated into existing retinal implants.
- Developing artificial retinas could not only restore vision but also lead to advancements in understanding brain signals, creating novel visual sensations, and improving brain interfacing technologies.
Enhancing Vision and Brain Function
1:01:08 - 1:08:11
- The podcast discusses the concept of being able to process multiple visual inputs simultaneously, using the example of driving and talking on the phone hands-free.
- Texting and driving is highlighted as a dangerous activity due to the brain's inability to effectively multitask between reading texts and focusing on fast-moving objects on the road.
- The potential for enhancing vision by stimulating different cell types in the retina independently is explored, with the idea of using an artificial retina device for research purposes.
- By understanding how different cell types transmit visual information, there is a possibility of augmenting vision and experiencing new visual sensations.
- The podcast touches on using engineering technologies to explore new visual capabilities and potentially apply them to enhance brain function.
Neuroengineering and Responsible Development
1:07:45 - 1:15:05
- Neuroengineering tools are being developed to stimulate specific cell types in the retina to mimic normal patterns of activation and potentially enhance vision capabilities.
- Advancements in neural augmentation through engineering are no longer just science fiction but a tangible reality that requires responsible development.
- The retina is considered an ideal starting point for neuro-prosthetics and neuro-engineering due to the deep understanding of its cell types and stimulation effects compared to other brain regions like the hippocampus.
- Pharmaceuticals targeting neuromodulators can have broad effects across the brain due to widespread receptor distribution, highlighting the importance of targeted neural augmentation technologies.
Plasticity of the Brain and Neural Implants
1:14:36 - 1:21:49
- Impressive advancements in technology are enabling paralyzed individuals to communicate and interact with devices using their thoughts.
- Understanding neural circuits and developing specific hardware is crucial for targeted interventions in brain functions.
- The retina holds potential for augmentation and better senses through electronic devices.
- Examining the neural retina can provide insights into neurodegenerative diseases like Alzheimer's, offering a window into brain health.
- Plasticity in the brain raises questions about its ability to adapt to increased sensory input, such as through retinal prostheses.
Neural Plasticity and Engineering Approaches
1:28:07 - 1:35:18
- Plasticity in the brain can be exhibited through gradual adjustments to the sensory world.
- Neurons adjust their strength of connectivity based on the timing of signals, influencing memory and visual function.
- Full control of the neural code with electronic implants can help teach the brain gradually rather than introducing sudden changes.
- An incremental and grounded approach is essential in engineering devices to augment the human brain.
- Smart neural implants that can sense and adapt to their surroundings are preferable over simple electronic devices.
Personal Journey and Self-Discovery
1:34:48 - 1:41:40
- The guest discusses their journey of exploring different paths before settling on neuroscience.
- They emphasize the importance of trying different things to find what one is good at and passionate about.
- Dance and music played a significant role in their personal development.
- The guest reflects on the value of wandering and experimenting in life to discover one's true calling.
- Their diverse experiences eventually led them to specialize in neuroscience, where they found their niche.
Intuition, Self-Love, and Purpose
1:41:17 - 1:49:02
- The speaker feels they have the right training and background to work on smart technology that can restore vision
- The speaker makes decisions based on feelings rather than thoughts
- The importance of knowing oneself, being oneself, and loving oneself is discussed
- The speaker practices meditation and astanga yoga to cultivate self-love and awareness
- Decisions are guided by feelings, with the feeling described as 'ease'
Recognizing Ease and Beauty
1:48:51 - 1:56:03
- The feeling of ease is significant in finding one's path and can be observed in body language.
- Recognizing ease in others involves observing various cues like breathing and pupil size.
- Some experiences, like encountering captivating energy or beauty, are best appreciated without dissecting them scientifically.
- Beholding moments of beauty can lead to a deep understanding and purposeful mission, as seen in the work on restoring vision and neuroengineering technologies.
The Nervous System and Human Experience
1:55:42 - 2:00:01
- The podcast guest discussed the advancements in understanding the nervous system and how it can lead to treating human diseases and expanding human experiences.
- The guest shared personal experiences related to their intuitive sense of beauty and taste, which they believe is guided by their nervous system.
- The host expressed gratitude for the guest's openness and knowledge sharing during the discussion.