WHAT IS THE HIPPOCAMPUS?

The hippocampus is a small but powerful region of the brain that plays a major role in memory, learning, and emotional regulation. In fact, the hippocampus isn’t a single structure. Rather, it’s a pair of thumb-sized structures located on the inside of the temporal lobes.

These are very special brain structures, because they house stem cells that can help produce new hippocampal cells under the right circumstances.

Research has suggested we can produce up to 700 new cells a day if we put the brain in a nourishing environment—meaning consuming good nutrition, taking omega-3 fatty acids, and getting adequate oxygen and blood flow to the brain. Findings in a 2025 study that used AI machine learning confirms that the human brain can indeed create new cells in the hippocampus.

WHAT CAUSES SHRINKAGE IN THE BRAIN’S MEMORY CENTERS?

1. Untreated Depression

Other than clouding your mood, long-term depression can trigger real, measurable changes in your brain, especially in areas critical to emotional balance and memory.

Research shows that people with untreated major depressive disorder often have a smaller hippocampus than those without depression. This helps explain the strong link between depression and memory problems.

When you’re depressed for a long time, your brain is repeatedly exposed to elevated levels of cortisol (the body’s primary stress hormone). Over time, this hormonal imbalance can damage brain cells, shrink the hippocampus, and interfere with the growth of new neurons.

The longer it goes untreated, the more damage may occur. That said, you can protect and restore your brain health through timely brain-based treatment designed to reduce shrinkage and support recovery.

2. Chronic Stress

If you’ve been dealing with ongoing stress, your brain is most likely flooded with cortisol. When elevated for long periods, the stress hormone can weaken the connections between your brain cells, reducing function in the hippocampus.

The way stress and brain function interact is deeper than most people realize. Chronic stress doesn’t just affect how you feel; it physically changes how your brain works and impacts your memory. It’s a slow, silent process that often goes unnoticed until it starts to impact your focus, memory, or emotional stability.

One study highlights that even moderate, persistent stress such as work burnout or relationship tension can cause forgetfulness, mood swings, and brain fog. That’s why managing stress through simple daily practices like deep breathing and mindfulness is key to protecting and restoring your brain’s memory center.

3. Poor sleep

Sleep might just be the most underrated brain healer out there. While you sleep, your brain sorts through memories, calms emotional noise, and does a bit of internal clean-up that you don’t even notice.

According to research, when you consistently cut short your sleep, especially getting fewer than six hours a night, your brain’s memory centers can begin to suffer.

This isn’t always obvious at first, but the effects tend to build quietly over time. Chronic lack of adequate sleep leads to memory loss, mood instability, and the gradual reduction of hippocampal volume over time.

You need to make consistent, restful sleep a priority. This isn’t only to boost your energy but also to protect and strengthen your brain. 

Press Play to See What Stress and Bad Habits Can do to Your Brain

In this video, Dr. Daniel Amen shares his first SPECT brain scan from when he was 37 years old and living in a high-stress environment. He shows how stress and some unhealthy habits can impact the brain, and how seeing his brain made him develop what he calls brain envy.

Click the link below to tune in: