Unlearning and Relearning: Neuroplasticity in Habit Change

By DMD Staff

Last updated: February 14, 2025

This article is the third part of a five part series on the neuroscience of habits. Read the first article here to start the series from the beginning.

Welcome to the third installment in our series on the neuroscience of habits. In our previous articles, we explored the fundamental habit loop and the powerful role dopamine plays in reinforcing our daily routines. Now, we turn to neuroplasticity—the brain’s remarkable ability to reorganize itself in response to new experiences. Understanding neuroplasticity is key to breaking old habits and establishing new, healthier ones.

What Is Neuroplasticity?

Neuroplasticity refers to the brain’s ability to change its structure and function in response to internal and external factors—like learning, environment, behavior, and emotion. Scientists once believed that the adult brain was relatively fixed after a certain age. Today, we know it remains plastic—meaning it’s always capable of adapting and rewiring. This adaptability underpins everything from recovering after a stroke to acquiring new languages later in life.

Neuroplasticity is also at the heart of how we unlearn and relearn behaviors. When you break a habit—smoking, for instance—you’re essentially directing your brain to weaken well-practiced neural pathways and strengthen new ones that promote healthier alternatives.

How Neural Pathways Form—and Re-form

A neural pathway is like a well-traveled road in the brain. The more you perform a particular action or think a particular thought, the “smoother” and more efficient that road becomes. This phenomenon is sometimes summarized as: “Neurons that fire together, wire together.”

Synaptic Pruning and Strengthening

• Pruning: When certain neural connections go unused, the brain gradually prunes them away to optimize processing.
  
• Strengthening: Repeated activation of specific pathways strengthens the synapses along those circuits, making signals travel more efficiently.

Think of it like trimming a tree: some branches get pruned back to allow stronger, more functional branches to flourish. This biological mechanism ensures that our brain is always adapting to focus on what we do most often—even if what we do most often is unhelpful.

Unlearning: Overwriting Old Habit Loops

Contrary to the idea that you can simply “delete” a habit, much of the unlearning process involves redirecting existing pathways or overriding them with better ones. While some neural connections do weaken over time without consistent use, fully “erasing” a habit is rare. More typically, the old behavior remains dormant, ready to reemerge under the right conditions—like stress or certain triggers.

Why Old Habits Resurface

• Residual Neural Imprint: The neural traces of your old habit still exist. If you face the same cue (say, a high-stress situation where you used to smoke), those pathways can light up again.
  
• Emotional States: Negative or positive emotional states can reactivate habit-related circuits. For instance, feeling anxious might resurface the habit of late-night snacking.

Overwriting Mechanism

When you overwrite a habit, you’re creating a competing pathway that becomes more rewarding or more frequently used than the old one. This process is underpinned by both dopamine’s reward prediction (discussed in our last article) and neuroplasticity’s continuous reshaping of the brain’s wiring.

Relearning: Building Better Behaviors

Just as old habits die hard, new habits can stick with surprising tenacity—if you give them the right conditions to root in.

1. Consistency: Repetition signals your brain to consider this new behavior “valuable.” Over time, consistent repetition fosters the synaptic changes that make the new action feel natural and automatic.
2. Positive Feedback: Reward mechanisms (including dopamine) accelerate the shift toward the new habit loop.
   
3. Contextual Cues: Linking a new habit to existing cues—known as habit stacking—helps embed it into the existing web of neural associations.

Neuroplasticity in Action

Research using brain imaging has shown that learning new skills—like juggling or playing a musical instrument—can produce observable changes in gray matter density in just a few weeks. Imagine applying the same principle to your daily behaviors. If you consistently reinforce a new habit (e.g., drinking water instead of soda), you could see tangible brain changes that support that choice over the long term.

Obstacles to Neuroplasticity

While our brains are inherently adaptive, certain factors can impede or slow neuroplastic changes:

1. Age: Although the brain remains plastic throughout life, children and adolescents generally exhibit more rapid, flexible neuroplasticity.
   
2. Stress and Anxiety: Chronic stress elevates cortisol levels, which can interfere with the formation of new neural connections.
   
3. Lack of Sleep: Sleep is crucial for memory consolidation and synaptic recovery. Insufficient sleep can hamper the brain’s ability to wire and rewire effectively.
   
4. Low Motivation: If the reward (intrinsic or extrinsic) doesn’t outweigh the effort of adopting new behaviors, the brain is less likely to invest energy in rewiring.

Practical Tips for Harnessing Neuroplasticity

1. Break It Down

   • Instead of changing everything at once, focus on one small habit at a time. Small, achievable goals create clear neural targets for your brain to rewire around.

2. Consistency Over Intensity

   • The brain learns best from regular, repeated exposure. Doing a short workout daily can be more effective at rewiring your exercise habit than one grueling session a week.

3. Pair with Positive Emotions

   • Positive emotional states facilitate plasticity. If a new behavior feels rewarding—socially, emotionally, or physically—you’re more likely to strengthen the neural pathways that support it.

4. Create Specific Cues

   • Use habit stacking by attaching your new habit to something you already do. For example, do 10 squats after brushing your teeth each morning. The established brushing routine acts as a cue to trigger the new behavior.

5. Practice Mindful Awareness

   • Mindfulness practices help you notice the exact moment you’re triggered to engage in an old habit. That awareness creates a brief window where you can choose to redirect your brain’s response.

6. Sleep and Recovery

   • Ensure you’re getting enough restful sleep. During certain sleep phases (like deep sleep and REM), your brain consolidates daily learning and prunes or strengthens synapses.

Key Takeaways

• Neuroplasticity is the biological basis for both unlearning harmful habits and relearning healthier ones.
  
• Old habits don’t necessarily vanish; they’re overwritten by stronger, more frequently activated circuits.
  
• Consistency and positive rewards help solidify new behaviors into ingrained habit loops.
  
• Factors like stress, lack of sleep, and low motivation can slow or hinder the brain’s adaptive changes.
  
• By leveraging cues, mindful awareness, and incremental improvements, you can consciously steer your brain toward more beneficial routines.

In our next article, we'll explore stress, emotion, and habit formation, examining how elevated emotional states can either derail your best intentions or, paradoxically, help you forge new paths. Until then, remember that every small step you take toward altering your habits is literally reshaping your brain—one synapse at a time.

Remember, your habits are not fixed. They are a dynamic interplay of environment, brain chemistry, and deliberate choices. Mastering them is the first step toward building a life that aligns with your long-term goals and values.