Along with shopping, gift-wrapping and cookie baking, I’m prepping for the holidays by accepting that family stress may get the best of me.

While I haven’t lived at home for over 20 years, conflict around heated topics like politics can make me feel like a misunderstood teen again. Listening calmly and objectively to my parents becomes harder and harder and I interrupt more. Once, I even rolled my eyes at my mom like a pouty adolescent.

My behavior, however, isn’t meant to be disrespectful or cruel, even though it might look that way. It’s actually a normal coping mechanism known as regression. As a psychologist, I’ve heard hundreds of family tales similar to mine. For many of us, reuniting with loved ones during the holidays can feel like psychological time travel.

There’s a reason why these visits trigger old memories and regressive behaviors. Psychological defenses are like emotional armor.

And there’s a reason why these visits trigger old memories and regressive behaviors. Psychological defenses are like emotional armor, protecting us from feeling more profound pain and anxiety, which explains why overwhelming emotions like anger, fear, or sadness can cause us to fall back on less mature expressions of emotion like passive aggression and, yes, eye-rolling. No matter how far away from home we travel, most of us can’t escape our family history — and the memories that come with it. New conversations remind us of old ones, even if we’re no longer living under our parents’ roofs.

“Families are systems that often preserve old roles to avoid greater conflict," says Molly Merson, a psychotherapist in Berkeley, California. “Returning home as an adult, you might rehash old arguments, habits, or return to comfortable ways of coping, because you’re reminded of feelings and experiences that you hoped to leave behind in childhood.”

Specific environmental cues can set off these memories. For instance, studies have found that familiar scents can prompt emotions, which explains why the smell of grandma’s pumpkin pie or mom’s homemade soup can trigger related recollections. Trauma researchers have also discovered that places, scent, and sounds associated with tragedies can cause painful memories to resurface.

Similarly, hearing certain songs can also remind us of past events. One study found that listening to music often evokes “autobiographical” memories, conjuring up positive and negative interactions with loved ones.

This isn’t simply an issue of childish habits returning, however. Unfortunately, leading independent, adult lives doesn’t necessarily mean that our parents don’t still see us as children. This in turn can put pressure on us to please them, an instinct that isn’t always synonymous with self-care. Caught in the mindset that looking out for ourselves means disappointing loved ones can cause guilty feelings to surface.

The good news is that understanding why regression occurs can help us gain insight into our actions, which can help shrink feelings of shame.

The good news is that understanding why regression occurs can help us gain insight into our actions, which can help shrink feelings of shame. While this knowledge may not prevent family friction, it’s a good reminder of the need to set boundaries during the holiday season.

“Everyone has a limit to how much time they can spend with family, and it’s important to know your boundary. You can’t say yes to every family request and expect to survive the season,” says Merson.

One technique: think through possibly stressful scenarios before heading home. Are extended visits likely to result in exhaustion, bickering and hurt feelings? If so, make a plan to take some space. If your parents insist that you stay with them, give yourself permission to say no, especially if you're introverted and know you need downtime.

When sharing your requests, express them graciously while making clear what you need. Family members, loved ones and co-workers feel validated when we appreciate them, and extending empathy can help them see where we’re coming from.

People of all ages may regress, but this defense mechanism is less likely when we are honest with ourselves and stay connected to how we’re feeling. Being able to name emotions like frustration, disappointment and sadness can make a world of difference. And even if we can’t share these feelings with family, talking or texting with an empathic friend or loved one can keep us grounded.

Obviously, changing family behavior is difficult. But we can lessen triggers by intercepting cues that may cause stress and strife.

If certain holiday songs awaken old, uncomfortable memories, put together a new playlist. If spending time together at home always ends in conflict, suggest eating at a restaurant instead.

In the end, taking these kinds of steps proactively can feel empowering, reminding us of what’s in our control and what’s not. And letting go of past attachments can feel freeing, allowing us to accept our quirky family members just as they are. The spirits of the Charles Dickens classic “A Christmas Carol” are fun to read about, but there’s no need to interact with our own ghosts every time we head home for the holidays.