How Nature & Other Physical Environments Impact Your Focus, Cognition & Health | Dr. Marc Berman

KEYPOINTS

• 01

  There are two kinds of attention, and only one fatigues

  Berman, a University of Chicago environmental neuroscientist, builds on his mentor Steve Kaplan's Attention Restoration Theory. Directed attention is choosing what to focus on, such as a lecture, paper or math problem, likely relying on frontal cortex. It runs down with use, which is why students start nodding off about 45 minutes into his lectures. Involuntary attention is captured automatically by something interesting and doesn't tire.

• 02

  Depleted directed attention costs more than focus

  Berman argues directed attention helps control nearly all behavior. When it is fatigued, impulse control drops, people can behave more aggressively and goals slip. He notes a puzzle: the brain uses about 20% of the body's energy whether you are sleeping or solving calculus, so the neural basis of mental fatigue is still unclear.

• 03

  Nature restores attention through 'soft fascination'

  Two ingredients matter. Natural settings make few demands on directed attention: no streets to cross, traffic or ads. They also offer softly fascinating stimulation, such as a waterfall's sound and froth, that engages involuntary attention while leaving room for your mind to wander. Times Square is 'harshly' fascinating: it grabs all your attention and leaves none for reflection.

• 04

  The benefit doesn't depend on enjoying it

  Mood improved on nature walks, but mood gains barely correlated with the cognitive gains. People who walked in January at 25 °F and hated it got the same working-memory boost as June walkers at 80 °F who loved it. Berman concludes something deeper than pleasantness is at work.

• 05

  Pictures and sounds help, but less than the real thing

  About 10 minutes of viewing nature photos, rating each from 1 to 3 to keep people engaged, also improved backwards digit span relative to urban photos. Nature sounds and videos help too. Berman cautions the effects are smaller than a real walk.

• 06

  Fractals and compressibility may explain the effect

  Natural scenes contain repeating fractal patterns, curved edges and color variation. Berman's student ran a JPEG compression algorithm on thousands of images, and nature scenes compressed into fewer bits than urban scenes, suggesting they may be easier for the brain to process. Brain signals measured by MRI and EEG are more fractal when the brain exerts less effort: in easy or well-practiced tasks, and less so with age. Nature may push the brain toward that restful state.

• 07

  Rumination doesn't spoil a nature walk

  Berman worried that walking alone might deepen rumination in depressed people. Instead, participants with clinical depression, deliberately prompted to recall a troubling memory first, gained even more working memory than non-clinical participants. He suggests nature frees attentional resources that rumination normally consumes.

• 08

  Restoration differs from meditation

  Meditation uses directed attention; nature restoration is passive and relies on involuntary attention. Berman wonders whether ancient practices held in beautiful settings combined both. Huberman frames the distinction as 'passive restorative' versus 'passive depleting' activities like phone scrolling, and speculates that focus circuits can strengthen or atrophy with use.

• 09

  A restorative environment needs extent and compatibility

  Kaplan's criteria include extent, meaning enough to explore, though not Yosemite scale. Berman's example is the roughly 100-square-meter Garden of the Phoenix near his office, with a path, a small waterfall and a view of Lake Michigan. The setting also has to fit your goals. For maximum benefit Berman suggests solitary time without phones, music or podcasts.