The Science of Hearing, Balance & Accelerated Learning | Huberman Lab Podcast #27

The Science of Hearing, Balance & Accelerated Learning | Huberman Lab Podcast #27 provides an overview of the science behind hearing and balance and how they can be used to enhance learning. The podcast covers topics such as the auditory and vestibular systems, tinnitus and emerging treatments, otoacoustic emissions, and the biology of balance. It also discusses the protocol of injecting short rest periods during learning tasks to improve learning outcomes. The video explores the role of headphones, white noise, and binaural beats in enhancing focus and attention. It also delves into the cocktail party effect, memory retention, and the Doppler effect. The video provides tips for improving balance and discusses the positive effects of self-generated forward motion on well-being and learning. It concludes with information on dizziness, lightheadedness, and motion sickness.

Overview of Topics

The main focus is on the science of hearing and balance and how they can be used to accelerate learning.
The auditory system and the vestibular system (balance system) interact with other systems in the brain and body, and understanding their mechanisms can improve learning and memory.
The podcast will also cover tools and protocols for utilizing these systems effectively.
The discussion will include tinnitus and emerging treatments.
Otoacoustic emissions, where the ears produce sounds that can influence others, will be explored.
Insights into the biology, brain, and inner ear associated with balance, as well as neuroscience, will be provided.
Recommendations for music that can enhance learning will be given.

Protocol: New Data for Rapid Learning

Injecting short periods of rest, specifically 10-second rest periods, during learning tasks can significantly enhance rates of learning and skill acquisition. These rest periods, referred to as micro-offline gains, allow the brain to continue rehearsing and processing information at a much faster speed, approximately 20 times faster. This effect, known as the spacing effect, has been hypothesized for a long time and has been demonstrated in various domains. The protocol involves injecting short periods of rest during the learning process, which has been shown to significantly improve learning outcomes. This technique can be applied to various domains of learning, including cognitive and physical skills. The underlying changes in neurons that occur during these rest periods contribute to the improvement in skill acquisition. The key takeaway is that incorporating rest periods during learning can greatly enhance the number of repetitions and ultimately improve learning. Additionally, taking a 20-minute nap or decompress period after a learning session may further enhance learning, although this has not been studied extensively.

Introduction: Hearing & Balance

The science of hearing and balance is the topic of this video. The speaker introduces the sponsors, Roka and InsideTracker, and highlights the features of Roka eyewear. The focus is on their high quality, lightweight design, optical clarity, and adaptability to changing lighting conditions. Roka eyewear is suitable for both active and everyday use, with a clean aesthetic and a variety of styles to choose from. The code "Huberman" can be used to save 20% off the first order on the Roka website. InsideTracker is mentioned as a personalized nutrition platform. The speaker also discusses the importance of regular blood work and DNA tests in understanding our body and health. InsideTracker provides easy-to-understand directives based on test results, allowing individuals to optimize their health through nutrition, exercise, and lifestyle factors. The video briefly mentions Headspace, a meditation app backed by studies that highlight the benefits of meditation for the brain and body. The app offers short and long meditation sessions to help individuals maintain a meditation practice. The speaker concludes by emphasizing the need for research in the areas of auditory system and balance to improve our understanding and potentially develop new therapies for hearing and balance disorders.

Roka eyewear: high quality, lightweight design, optical clarity, adaptability to changing lighting conditions, suitable for active and everyday use, clean aesthetic, variety of styles
InsideTracker: personalized nutrition platform, provides easy-to-understand directives based on test results, optimize health through nutrition, exercise, and lifestyle factors
Headspace: meditation app, benefits of meditation for brain and body, offers short and long meditation sessions
Importance of research in auditory system and balance for understanding and developing therapies for hearing and balance disorders.

How We Perceive Sounds

Our perception of sounds is influenced by the design of our ears, specifically the outer part called the pinna, which amplifies high-frequency sounds and captures low-frequency sounds. Sound waves enter our ears and vibrate the eardrum, connected to a hammer-shaped bone called the malleus. The cochlea, a snail-shaped structure in the inner ear, converts sound waves into electrical signals that the brain can understand. This process involves the movement of the eardrum and the malleus, allowing the cochlea to separate sounds of different frequencies. Hair cells within the cochlea send signals to the brain indicating the presence of specific sounds. The cochlea acts as a prism, breaking down sounds into different frequencies, which the brain interprets to make sense of the sounds.

Your Hearing Brain (Areas)

The hearing process involves transmitting information from the cochlea to various stations in the brain before reaching conscious awareness.
Stations in the brain involved in the hearing process include the spiral ganglion, cochlear nuclei, superior olive, inferior colliculus, and medial geniculate nucleus.
Auditory information is ultimately processed in the neocortex.
Processing auditory information before conscious detection is crucial due to the complexity of this pathway.

Localizing Sounds

The brain uses auditory and visual cues to localize sounds in space, with disruptions leading to the ventriloquism effect. The brainstem plays a crucial role in sound localization through interaural time differences. The shape of our ears modifies sound frequencies, allowing us to determine the direction of sounds. Cupping our hands around our ears enhances sound localization. Timing and frequency differences between our ears help us accurately determine sound direction.

Ear Movement: What It Means

Humans have limited ability to move their ears compared to other animals
About 60% of people can consciously move their ears without touching them, but the movement is subtle
Moving the eyes to the left or right can cause ear muscles to contract
Raising one eyebrow is difficult for humans, as it requires cramping down one side of the face
Ear movement is controlled by the same motor pathway as raising one eyebrow
Men are typically more able to move their ears than women
Ear movements correlate with other aspects of biology, such as eye movements
Ear movement is crucial for hearing, balance, and locating the source of a sound
Understanding ear movement can lead to improved learning and cognitive abilities.

Your Ears (Likely) Make Sounds: Role of Hormones, Sexual Orientation

The role of hormones and sexual orientation in the sounds produced by our ears is explored in this summary. Key points include:

Otoacoustic emissions are sounds made by the ears, with 70% of people producing them unknowingly.
Heterosexual women have a higher frequency of otoacoustic emissions compared to heterosexual men.
Homosexual and bisexual women have fewer otoacoustic emissions than heterosexual women.
These differences suggest that hormone exposure during development may shape the hearing apparatus.

Binaural Beats: Do They Work?

Binaural beats are sound waves that can stimulate different brain states, such as sleep, relaxation, alertness, focus, and learning. They have been shown to be effective in improving sleep, meditation, recall, sustained thought, and incorporating new information. Binaural beats can also reduce anxiety and treat chronic pain. While they can modestly improve cognition and creativity, their main benefits lie in anxiety and pain reduction. They can create a focused environment for studying and learning, and are accessible through apps. The impact of background noise on brain states for learning is still debated.

White Noise Can Enhance Learning & Dopamine

White noise can enhance learning and dopamine release in the brain by modulating activity in dopaminergic mid-brain regions and the right superior temporal sulcus. It improves performance in auditory working memory tasks and enhances brain function for learning different types of information. However, caution should be taken with infants and young children as white noise may have detrimental effects on auditory learning and development. The optimal volume of white noise varies from person to person and should be loud enough to be heard but not intrusive or irritating. High volume levels should be avoided, especially when using headphones.

Headphones

Headphones have the effect of making sounds appear to come from inside the head rather than the environment. This can be beneficial for studying or learning, as it raises the baseline of dopamine release, increasing attention and motivation.

Key points:

Using headphones with white noise can enhance focus and attention.
Keep the volume low to avoid distraction and create a slight increase in dopamine release.
Find a volume that allows complete focus on the task at hand.

However, headphones can cause hearing loss if used at high volumes, especially in loud environments. It is important to protect our hearing by using earplugs or low-profile headphones in loud environments.

Key points:

Loud sounds in loud environments can permanently damage the hair cells in our ears.
Exposure to loud environments over time can lead to hearing loss.
Avoid sudden inflections in sound above the threshold in loud environments.

To preserve hearing, it is recommended to listen at lower volumes. The argument that high volumes help avoid listening to unwanted people is not valid, as they can simply send text messages instead. The impact of white noise on hearing loss during development is not discussed.

White Noise During Development: Possibly Harmful

White noise during development can potentially be harmful to the auditory system, disrupting tonotopic maps responsible for higher-level cognition and decision-making. Exposure to white noise in young animals suggests a potential negative impact on the auditory system. White noise lacks tonotopic information and can disrupt the formation of tonotopic maps, reducing the precision of auditory processing. It is suggested to avoid white noise or opt for alternatives like pink noise, especially for young children. Background white noise in adulthood is not a problem and can enhance learning.

Remembering Information, The Cocktail Party Effect

The cocktail party effect refers to our ability to selectively attend to specific sounds in a noisy environment, such as a cocktail party. Our brain creates a cone of auditory attention, allowing us to extract the information we care about while ignoring the rest. This process requires attention and consumes energy. Researchers have studied the mechanisms behind this phenomenon and have identified ways in which our brain accomplishes this feat.

Humans can expand or contract their auditory field of view, similar to their visual field of view.
Selectively attending to certain sounds requires energy, effort, and attention.
Humans pay attention to the onset and offset of words to extract particular sounds from a noisy background.
The cocktail party effect can be beneficial for learning and extracting sound information.
Remembering specific details, such as someone's name, can be challenging in noisy environments.
Memory is influenced by the clarity of the signal and the level of background noise.
Paying attention to the onset and offset of words or sounds can improve memory.
Selectively focusing on key words or information is more effective than applying the technique to every word.
Deliberately encoding auditory information can enhance learning and accelerate the learning process.

How to Learn Information You Hear

The most profound aspect of the topic is that by selectively focusing on specific elements of speech or sound, individuals can learn information more effectively and activate neuroplasticity in the adult brain.

Using the attentional system allows for faster learning and neuroplasticity in the adult brain.
Passively listening to information does not allow for brain changes or memory retention.
Paying attention to specific frequencies within speech or sounds can lead to quicker learning and changes in neural architecture.
Neuroplasticity is not limited to the developing brain; the adult brain is also capable of change.
Selectively focusing on certain words, frequencies, scales, or keys when learning music or reciting information can improve information retention.
Directing attention to particular features of speech can increase overall attention and improve learning.
It is not necessary to focus on every word, but rather on specific themes or elements within the content.
The auditory system can selectively focus on certain elements of sound, similar to the cocktail party effect.
Paying attention to the onset and offset of words or specific notes in music, as well as broader elements like motifs or phrases, can extract more information overall.

Doppler

The Doppler effect is the way we experience sound when the source of the sound is moving. It helps us determine the direction and speed of objects approaching us, and plays a crucial role in our ability to avoid potential dangers. Bats use the Doppler effect to navigate their environment and "see" in the dark.

Tinnitus: What Has Been Found To Help?

Tinnitus, or ringing in the ears, can be influenced by stress levels and damage to the ear's hair cells. While there is no cure for tinnitus, there are treatments that may help alleviate symptoms. Some substances like melatonin, Ginkgo bilboa, zinc, and magnesium have shown potential in reducing tinnitus symptoms. However, more research is needed in these areas. Other approaches include avoiding loud noises, managing stress, using sound therapy, trying certain medications, and exploring alternative therapies. It is important to consult with a healthcare professional for the best course of action.

Aging: How Big Are Your Ears?

The size of our ears can indicate our biological age, with larger ear sizes indicating older age. By measuring the circumference of our ears and using a specific formula, we can determine our biological age. This is based on the fact that as we age, our ears grow more quickly.

Key points:

The rate of ear growth correlates with our biological progression through life
Collagen synthesis, which is a marker of age, shows up prominently in our ears
Understanding and improving balance is also discussed.

Balance: Semi-Circular Canals

The semi-circular canals in the ears are crucial for balance and detecting head movements. They consist of three hula hoop-like structures representing different planes of movement. The canals contain calcium-like deposits that move and deflect hair cells, sending information to the brain about head position and movement. The vestibular system, including the canals, works with the visual system to provide accurate information. Hair cells in the canals are activated when the head moves, sending signals to the brain about the direction of movement. Visual information also helps determine head location.

A Vestibular Experiment

Moving your body slowly disrupts the vestibular and visual systems, while moving quickly allows the signal to reach the brain and eyes more efficiently. This phenomenon can cause discomfort and motion sickness. Looking up or to the side can also trigger these effects.

Summary: The vestibular experiment aims to uncouple the visual and vestibular mechanisms in the inner ear. By moving the head from side to side and nodding up and down, the experiment demonstrates that these mechanisms normally work together to guide eye movements and maintain balance.

Key points:

Moving slowly disrupts the vestibular and visual systems, causing discomfort and motion sickness.
Moving quickly allows the signal to reach the brain and eyes more efficiently.
Looking up or to the side can trigger these effects.
The vestibular experiment aims to uncouple the visual and vestibular mechanisms in the inner ear.
The experiment involves moving the head from side to side and nodding up and down.
The experiment demonstrates that these mechanisms normally work together to guide eye movements and maintain balance.

Improve Your Sense of Balance

Improving your sense of balance involves incorporating visual cues and understanding the relationship between your visual system and balance system. Here are the key points to consider:

Visual cues provide feedback to the vestibular system, which affects balance.
Practice raising one leg and focusing on a short distance, gradually extending the visual focus further away, and then bringing it back.
Understanding the balance system includes the semicircular canals, which communicate with the cerebellum and combine visual information with your body map.
Enhancing balance requires activating and adjusting postural muscles in response to changes in your visual world.
Engaging in movement is a robust way to stimulate changes in your visual environment.
Combine changes in your visual environment with static postures or visual views to cultivate a sense of balance.
Balance training, including moving vision while maintaining a balanced position, unilateral movement, and generating tilt or imbalance in limb activation, has been shown to be effective.
Cultivating and strengthening the vestibular system is another effective approach to improving balance.

Accelerating Balance

Accelerating balance involves engaging the vestibular system, visual system, and semicircular canals to enhance balance in a dynamic way. Activities that involve accelerating forward while being tilted with respect to gravity, such as skateboarding or biking, are the best way to cultivate a better sense of balance. The cerebellum plays a role in balance, skill-learning, and timing of movements.

Self-Generated Forward Motion

The most profound aspect of the topic of Self-Generated Forward Motion is the positive effect it has on overall well-being and accelerated learning.

Key points include:

The activation of the cerebellum through tilting the head and body during forward acceleration releases neuromodulators like serotonin and dopamine, which make us feel good and enhance learning.
Engaging in activities that involve forward acceleration while tilted, such as surfing, can provide these benefits.
Engaging in modes of acceleration while tilted, such as snowboarding or cycling, strengthens the vestibular system and improves balance.
Roller-coasters trigger the release of neuromodulators that make us feel good, but some individuals may experience nausea.
It is recommended to safely incorporate acceleration and head/body tilt into routines to enhance balance skills and enjoy the pleasurable effects of forward motion.

Dizzy versus Light-Headed

Feeling dizzy and feeling lightheaded are two distinct sensations. Dizziness is characterized by the perception of spinning while being able to focus on a stationary object, whereas lightheadedness is the feeling of falling or needing to get down. The causes of these sensations can vary, including low blood sugar, dehydration, and low electrolyte levels. Adding salt to water can help alleviate lightheadedness caused by low electrolytes.

Motion Sickness Solution

Motion sickness occurs when there is a disconnect between visual and motion information received by the vestibular system. To prevent motion sickness, it is important for the visual system to track with the vestibular system. Here are some key points to alleviate motion sickness:

Avoid fixating on objects inside the vehicle and instead look out the front windshield.
Focusing on objects close to you can be problematic, while looking off into the horizon helps.
Sitting in the back of a moving vehicle and looking at a phone or reading a book can cause motion sickness.
Fixating on a particular location on the horizon is not ideal.
Driving can help alleviate motion sickness by providing proprioceptive feedback to the vestibular system.

Synthesis

The video explores the science of hearing, balance, and accelerated learning.
It discusses how sounds are processed by the brain and the effects of low-level white noise and binaural beats on brain states and learning.
The relationship between the vestibular apparatus, visual system, and gravity in enhancing learning and balance is also explored.
The video mentions supplements from Thorne and provides information on how to support the podcast.