Essentials: Tools to Boost Attention & Memory | Dr. Wendy Suzuki

Memory and attention are not fixed traits; they are physiological processes that can be strengthened, optimized, and protected. In a compelling discussion on the Huberman Lab Essentials series, Dr. Wendy Suzuki, a professor of neurobiology and psychology at New York University, breaks down the science of how we learn and remember. Beyond the classroom theories, Dr. Suzuki shares her personal and professional journey discovering the profound impact of physical movement on the brain.

While many associate exercise strictly with cardiovascular health or weight management, the neuroscience reveals a different story: movement is perhaps the most transformative tool available for cognitive function. From growing new brain cells to staving off neurodegenerative decline, the protocols discussed here offer a blueprint for building a resilient, high-performing brain.

Key Takeaways

• The Four Elements of Memory: To make information stick, the brain relies on novelty, repetition, association, and emotional resonance.
• The "Bubble Bath" Effect: Every time you exercise, you bathe your brain in neurochemicals like dopamine and serotonin, along with critical growth factors like BDNF.
• Neurogenesis is Real: Contrary to older scientific beliefs, humans can grow new neurons in the hippocampus well into their ninth decade of life.
• Timing Matters: The optimal time to exercise is immediately before you need to utilize your brain for focused work or learning.
• Minimum Effective Doses: Just 10 minutes of walking can shift mood, while consistent 30-45 minute cardio sessions are required to build long-term hippocampal volume.

The Anatomy of a Memory

To understand how to improve memory, one must first understand what makes an event memorable in the first place. Dr. Suzuki identifies four distinct factors that determine whether the brain encodes a perception into long-term memory.

The Four Pillars of Memorability

1. Novelty: The brain’s attentional systems are naturally drawn to new experiences. When a stimulus is novel, the brain prioritizes it over routine information.
2. Repetition: This is the brute force method of learning. Repeated exposure strengthens the neural pathways associated with a specific piece of information.
3. Association: The brain learns by linking new information to existing knowledge. For example, meeting someone who knows many of the same people you do makes them easier to remember than a complete stranger with no shared connections.
4. Emotional Resonance: The amygdala, the brain's emotional processing center, interacts with the hippocampus to "stamp in" memories. This is why we vividly remember our happiest and saddest moments while forgetting the mundane.

The Hippocampus and Imagination

The central structure for long-term memory is the hippocampus. Historically, neuroscientists viewed this structure strictly as a recording device for the past. However, modern research suggests a more expansive role. The hippocampus is essential for association—linking the "what, where, and when" of events.

Crucially, this associative power is also what allows for imagination. Without a functioning hippocampus, one cannot easily imagine future scenarios or events that haven't happened yet. Therefore, protecting this structure is not just about preserving the past; it is about maintaining the capacity to envision the future.

Exercise as a Neurochemical "Bubble Bath"

Dr. Suzuki’s research pivot from pure memory physiology to the effects of exercise began with a personal realization: after increasing her own physical activity, her ability to focus and write grants improved significantly. This led to the study of how movement biologically alters the brain.

When you move your body, you release a cascade of neurochemicals, including dopamine, serotonin, and noradrenaline. These improve mood and focus immediately. However, for long-term memory protection, the most critical release is a protein called Brain-Derived Neurotrophic Factor (BDNF).

"It's like giving your hippocampus a boost... We all have the capacity to grow a bigger, fatter, fluffier hippocampus."

BDNF acts directly on the hippocampus to stimulate neurogenesis—the growth of new brain cells. While you cannot cure Alzheimer's or dementia once they have fully set in, building a "bigger, fatter, fluffier" hippocampus creates a cognitive reserve. This reserve means that even if neurodegeneration begins, it will take longer for the disease to impact daily function significantly.

Mechanisms and Protocols for Brain Health

Understanding why exercise works is motivating, but knowing how to apply it is transformative. The conversation highlighted several specific mechanisms and protocols for leveraging exercise to boost brain power.

The Pathways to Neurogenesis

How does moving a muscle result in new brain cells? There are two primary pathways identified in current research:

• Myokines: When striated muscles contract (as in running or lifting), they release proteins called myokines. These cross the blood-brain barrier and stimulate the release of BDNF.
• Liver Ketones: Exercise acts as a physiological stressor. In response, the liver releases a ketone called beta-hydroxybutyrate. This ketone also crosses the blood-brain barrier and triggers BDNF production.

Practical Exercise Protocols

You do not need to be a marathon runner to reap cognitive benefits. The research points to scalable benefits depending on intensity and duration:

• For Mood Enhancement: A mere 10 minutes of walking is sufficient to shift mood through dopamine and serotonin release.
• For Brain Building: To stimulate neurogenesis and improve hippocampal function, cardiovascular exercise is key. The goal is to elevate the heart rate for 30 to 45 minutes.
• Frequency: Studies on low-fit individuals (ages 30–50) showed that exercising just 2–3 times per week for three months resulted in significant improvements in mood, body image, and memory tasks.
• Volume Matters: For those who are already "mid-fit," increasing frequency (up to 7 times a week) correlated with even better mood and hippocampal memory scores. Essentially, "every drop of sweat counts."

The Best Time to Exercise: While any exercise is better than none, the optimal time is immediately before a demanding mental task. Because the acute effects of improved focus and reaction time last for up to two hours post-workout, morning exercise is often the most strategic choice for knowledge workers.

Beyond Cardio: Affirmations, Meditation, and Sleep

While aerobic exercise is a powerhouse for the brain, Dr. Suzuki emphasizes a holistic approach to attention and memory that includes positive self-talk, stillness, and rest.

The Role of Affirmations

Dr. Suzuki advocates for a practice known as "IntenSati," which combines physical movement with spoken affirmations (e.g., punching while saying "I am strong"). The research suggests that positive affirmations can alter mood and interrupt the negative internal monologues that many people struggle with. By combining the mood-boosting chemicals of exercise with deliberate positive self-talk, the psychological benefits are amplified.

Meditation for Focus

For those looking to improve attention span, meditation is the gym for the mind. You do not need to meditate for an hour to see results.

"Just 10 minutes of walking outside can shift your mood... [and] 12 minutes of body scan meditation... significant decreases in stress response."

In a study conducted by Dr. Suzuki’s lab, participants who performed a 12-minute daily guided body scan for eight weeks showed reduced stress responses and improved cognitive performance. The mechanism here is the practice of returning focus to the present moment, counteracting the brain's tendency to dwell on past traumas or future anxieties.

Conclusion

The neuroscience is clear: the brain is plastic, and it responds robustly to lifestyle inputs. By integrating specific tools—specifically cardiovascular exercise, short-form meditation, and adequate sleep—we can physically alter the structure of our brains.

Whether the goal is to ace a professional project, improve mood, or build a cognitive buffer against aging, the strategy remains the same. It requires consistent, heart-pumping movement and the discipline to rest and center the mind. As Dr. Suzuki notes, this isn't just about living longer; it is about living with higher cognitive quality for as long as possible.