Alcohol’s Effect on the Central Nervous System

Slurred speech. Stumbling steps. Embarrassing ourselves in public. Everyone knows what happens when someone has a few too many drinks. But have you ever wondered what really goes on in your brain when you drink? If so, buckle up for a Magic School Bus-style ride into our central nervous system.

We will learn all about our central nervous system, how alcohol impacts it, and ways we can set ourselves up for a healthy brain!

The Central Nervous System: Our Body’s Command Center 

The central nervous system (CNS) is responsible for coordinating and processing sensory information, initiating voluntary and involuntary movements, and regulating body functions. It is made up of our brain and spinal cord, which each have distinct and vital functions. 

The Brain

Our brain is our command center and controls all of our body's actions and activities. The brain is made up of neurons or the cells in our brain that facilitate communication and allow us to do everything from thinking and perceiving to sensing and breathing. 

The Spinal Cord

Our spinal cord is a cylinder structure that runs from the brainstem to our lower back through our vertebral column (spine). Without the spine or bone protecting the spinal cord, it is very delicate as it contains bundles of nerve fibers. These nerves carry messages to and from our brain to the rest of our body or the peripheral nervous system. The spinal cord also facilitates reflex actions, which are rapid responses to stimuli that bypass the brain for quicker reactions.

Neurotransmitters

Neurotransmitters are chemicals in our CNS that neurons use to communicate with each other. In our CNS, there are tiny gaps between our neurons called synapses. Essentially, neurotransmitters carry messages in the synapse from one neuron to another. Once in the synapse, neurotransmitters find their way to proteins on other neurons called receptors, which they bind to and trigger changes in the receiving cell. 

The main neurotransmitters include glutamate, gamma-aminobutyric acid (GABA), serotonin, dopamine, epinephrine, norepinephrine, and acetylcholine.

Through the brain, spinal cord, and neurotransmitters, our CNS controls and coordinates all of our body functions and ensures we survive or adapt to our environment. 

How Does Alcohol Consumption Affect the Central Nervous System?

Alcohol is a depressant, meaning it slows down the CNS. As we learned above, alcohol affects almost all of our neurotransmitters, but alcohol’s depressing effects come from the increase in GABA. Let’s break down a little more about how alcohol can impact our brain and spinal cord. 

Alcohol and the Brain

Alcohol can impact our brain in many ways, mostly by slowing it down. In our brain, alcohol changes our neurotransmitters, which then change the way we act. Additionally, long-term alcohol use can make more permanent changes, such as altering our brain receptors and shifting some of our brain structures (more on that later!). 

Alcohol and the Spinal Cord

It’s not discussed as often, but alcohol can also impact our spinal cord in several ways: 


• Neurotransmitter dysfunction. The most prominent inhibitory neurotransmitter in the spinal cord is glycine. Alcohol increases glycine, which can impact our sensation and movement. 
• Damage to spinal cord tissue. Chronic alcohol abuse can lead to nutritional deficiencies and neurotoxicity, which can damage spinal cord tissue over time. This damage may manifest as neurological symptoms such as weakness, numbness, or tingling in the extremities.
• Disrupted spinal cord blood flow. Excessive alcohol consumption can also affect blood flow to the spinal cord. Reduced blood flow deprives spinal cord tissue of oxygen and nutrients, which can lead to tissue damage and dysfunction.

Alcohol consumption can have a range of negative effects on spinal cord function, from acute impairment of motor skills to long-term damage and increased risk of injury.

Alcohol and Neurotransmitters

Every movement we make requires many neurons and neurotransmitters. Taking a single step, for example, requires dopamine, acetylcholine, glutamate, and GABA. Together, these neurotransmitters signal between neurons to help us move. As alcohol can impact all of these neurotransmitters, we can see how intoxication disrupts our movement and coordination. 

Because each neurotransmitter plays a different role, each one is impacted differently by alcohol: 

• Glutamate. Glutamate is important for functions such as learning, memory, sleep, and wakefulness. Alcohol decreases glutamate activity, impairing our memory and disturbing our sleep patterns. 
• GABA. GABA helps our brain slow down and relax. Alcohol notoriously increases GABA levels, often making us feel disinhibited and carefree. 
• Serotonin. Serotonin is known as our “happy chemical,” but it is also important for sleep, appetite, digestion, learning, and memory. Acute alcohol exposure increases the release of serotonin, making us feel temporarily happier. 
• Dopamine. When dopamine is released, we feel pleasure, satisfaction, and motivation. Alcohol increases our dopamine levels, making us feel pleasure when we first drink it. 
• Epinephrine. Epinephrine, also known as adrenaline, is both a neurotransmitter and a hormone that plays an important role in our fight-or-flight response. Alcohol raises levels of epinephrine, which can make it harder to sleep or increase our heart rate. 
• Norepinephrine. Norepinephrine is a hormone and neurotransmitter that increases arousal, alertness, focused attention, and increased restlessness. Alcohol increases norepinephrine levels, which can also increase blood pressure, nervousness, and headaches.
• Acetylcholine. Acetylcholine plays an important role in memory, learning, attention, arousal, and involuntary muscle movements. Alcohol increases acetylcholine in the brain, which partners with dopamine to create those “rewarding” feelings of alcohol. 

Not only does it take multiple neurotransmitters to complete an action, but our neurotransmitters also rely on each other to maintain safe levels. For instance, GABA helps regulate how much glutamate is in our system because too much glutamate can be harmful to our neurons. This is known as the homeostasis of our neurotransmitter system. Alcohol interferes with this delicate balance, both in the short term and long term. 

Long-Term Effects of Alcohol on the Central Nervous System

Long-term alcohol use can impact the CNS in many ways. Let’s review some of the most profound ways alcohol can make long-term changes to our CNS: 

• Neurotransmitter receptors. Over time, alcohol use depletes the neurotransmitters that make up our brain’s reward system: dopamine, serotonin, and GABA. Because the brain adapts to the short-term boost of these neurotransmitters in acute alcohol use, it needs more and more alcohol to produce the same “rewarding” feeling alcohol provides. The result is greater dependence and withdrawal symptoms. 
• Brain structures. Too much alcohol over time can damage and shrink brain cells. Researchers found areas of the brain most affected include our emotion regulation center, known as the limbic system, and the frontal cortex, the area used in higher-order thinking and decision making. 

The changes in our neurotransmitters and brain structures contribute to the behavioral alterations with long-term alcohol use. These changes in the CNS make the cycle of alcohol misuse hard to break. 

How To Nourish Your Central Nervous System

Alcohol use can disrupt our CNS. The good news: there are ways we can help nourish our CNS! Let’s go through some strategies for promoting a healthy CNS:

• Eat healthy fats. Fat is crucial for our CNS as the brain is nearly 60% fat! Incorporating fats such as omega-3 fatty acids from foods such as fish, walnuts, soybeans, chia seeds, or flaxseeds. Our brain uses fat to insulate our neurons to make communication smoother. Overall, eating a well-rounded, nutrient-rich diet is good for your brain health. 
• Exercise. Engaging in regular exercise can improve our brain health in several ways. First, exercise increases blood flow to the brain, which brings nutrients and oxygen to the brain to fuel it. Exercise can enhance your mood, reduce stress levels, enhance motor skills, balance, and proprioception that are controlled in the brain. Physical activities can also help protect your brain against cognitive decline. 
• Sleep. Your brain uses sleep to restore and repair your brain. Sleep is essential to maintain cognitive function, emotional stability, and brain health. Prioritizing sleep will help keep your brain healthy. 
• Stress management. Chronic stress can negatively impact your nervous system and lead to CNS dysfunction. Managing stress in healthy ways (without alcohol) is a great way to keep your CNS healthy. Some ways to manage your stress without alcohol include exercise, meditation, or mindfulness. 
• Regular neurological checkups. Staying ahead of the game with regular neurological checkups with neurology experts can help you stay proactive with your brain health.  

Taking care of your brain is essential to CNS and overall health. The better you take care of your CNS, the better it will take care of you. 

Key Takeaways

Alcohol is a central nervous system depressant. Alcohol changes our brain chemistry and structure, which causes behavior changes, both short term and long term. When we cut back or quit alcohol, our brain will start to recover from the long-term effects of alcohol.