Robert's family called me panicked. "He's getting so much worse. The confusion starts at 3pm now instead of 5pm." Nothing had changed medically. Except daylight saving time ended. This is sundowning. And most families have no idea what's happening. Here's what I see in clinic: Around 4-6pm, patients with dementia can transform. Calm morning. Cooperative afternoon. Then suddenly: Intense anxiety. Aggressive outbursts. Seeing people who aren't there. Trying to "go home" when they're already home. Their brain's internal clock is broken. The suprachiasmatic nucleus controls circadian rhythm. In dementia, it degenerates early. So external cues matter enormously. Sunset. Shadows. Evening routine changes. All trigger the brain's confusion alarm. Why evening specifically: - Mental fatigue accumulates all day. By evening, cognitive reserves are depleted. - Dimming light creates visual confusion. Shadows look like threats. - Medication timing. Many psych meds peak in afternoon, wearing off by evening. - Caregiver stress. By 5pm, caregivers are exhausted too. Patients sense it. The daylight saving time effect: Robert's brain expected darkness at 5pm. That was his "bedtime routine trigger." Clock changed. Suddenly it's dark at 4pm. His brain thinks bedtime moved up an hour. Triggers evening confusion an hour earlier. What actually helps: Bright light therapy from 4-8pm. 1,000+ lux. Tricks the brain into thinking it's still afternoon. Not strong or late enough to disrupt sleep. Consistent schedule regardless of clock. If dinner was 6pm before time change, keep it 6pm after. Reduce afternoon stimulation. Save baths, doctor visits, family gatherings for morning. Address basic needs proactively. Bathroom. Snacks. Comfortable temperature. Before confusion starts. What doesn't help: Reasoning with them during episodes. Their reality is different. You can't logic someone out of brain damage. Asking "don't you remember?" Of course they don't. That's the disease.