Nature. Image by Tim Sandle
Between mid-October and mid-November, something in me shifts. The light softens, the air sharpens, and my thoughts seem to settle into focus. I feel more connected to nature and more content, as if my mind and body fall into sync with the world around me. For years, I treated this as a simple fondness for autumn. Now, I see it as biology at work.
By Scott Hutcheson, PhD
Humans evolved in rhythm with the planet’s cycles. Before clocks, calendars, or quarterly reports, we relied on natural cues to govern when to hunt, plant, rest, and reflect. That deep synchronization with the environment has not disappeared. It still lives in our biology, quietly shaping our mood, attention, and motivation. Some people feel most alive in the energy of spring. Others come to life in the long days of summer or the stillness of winter. These are not just preferences; they are expressions of our circannual biology, the seasonal patterns that influence how we think, feel, and act.
The Biology of Seasonal Attunement
Our bodies regulate themselves through interconnected clocks. The circadian rhythm governs daily cycles like sleep and alertness. The circannual rhythm operates more slowly, syncing with the Earth’s orbit around the sun. Large-scale datasets show that human gene activity shifts with both day–night and season across tissues, indicating that biology itself is time-tuned. A Nature Communications study found that more than 4,000 human genes vary in activity depending on the time of year. Research shows that hormones, neurotransmitters, and immune responses fluctuate seasonally in nearly every species, humans included.
As daylight shortens, melatonin begins its nightly rise earlier, cueing rest and introspection. Journal of Neuroscience research shows seasonal effects on dopamine synthesis, helping explain why serotonin and dopamine levels stabilize, often producing a quieter, steadier mood. Cortisol, the stress hormone, tends to decline slightly, easing the nervous system from high alert to reflective mode. This combination of lower stress and higher stability helps explain why autumn often feels grounding and clear. Biologically speaking, it is the body’s signal to consolidate, conserve, and prepare for renewal.
Our sensory systems reinforce the effect. Cooler temperatures sharpen olfactory perception, and the air carries fewer competing smells, making scent and memory more vivid. The acoustic environment also changes: leaves absorb sound, and migrating wildlife soften the soundscape. These quieter, simpler inputs reduce what neuroscientists call environmental noise, allowing for greater perceptual coherence and calm. For those who are sensitive to seasonal shifts, clinicians note how reduced light drives changes in sleep and mood.
Evolutionary Echoes
For much of human history, this time of year meant survival. The harvest was in, food stores were full, and communities turned inward to share, reflect, and prepare for scarcity. That pattern likely rewarded behaviors tied to safety and belonging. Modern imaging studies echo this biological seasonality, showing changes in serotonin transporter binding and, in emerging work, dopamine receptor availability across seasons. The same circuitry still activates today when we gather around a meal, light a fire, or take long walks under changing leaves. What feels like nostalgia is often our biology recognizing an ancient rhythm of completion and security.
Not everyone resonates with autumn. Some feel most aligned with the novelty of spring or the stimulation of summer. Differences in how our clocks and neurotransmitter systems respond to light and season help explain this variation. Reviews and population-level studies continue to map how these rhythms influence behavior and mood.
Rhythms of Leadership and Work
The challenge for modern leaders is that organizational life often ignores these natural oscillations. We plan as if energy, focus, and motivation are constants. In reality, both individuals and teams function in biological cycles of activation and recovery.
Understanding these cycles can make us more effective and humane leaders.
Autumn is the season of reflection and consolidation. It is a natural time for reviewing progress, harvesting lessons, and strengthening connection. Winter favors deep work, strategic thinking, and quiet planning. Spring supports ideation and exploration. Summer energizes execution, visibility, and scaling.
Leaders who attune to these rhythms, not as rigid schedules but as behavioral patterns, can create environments that align with how humans actually function. When we push through winter expecting constant output or ignore the need for autumnal reflection, performance eventually suffers. Our biology keeps its own score.
Practical ways to Lead in Rhythm
Here are four suggestions for leading with seasonal intelligence.
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Observe your own peak season. Reflect on when you feel most creative, focused, or relational. Track how your energy and mood shift month to month. That awareness becomes a behavioral compass for scheduling demanding or restorative work.
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Align team rhythms with natural energy arcs. Use late autumn for retrospectives, winter for planning, spring for experimentation, and summer for scaling. Even symbolic alignment helps people feel in sync with a larger pattern.
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Simulate your preferred season when needed. If you thrive in autumn but face the chaos of midsummer, adjust light exposure, temperature, and sensory cues. Lower lighting and cooler air, for example, promote the same parasympathetic calm associated with fall.
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Normalize cyclical performance. High-functioning teams move through seasons of intensity and reflection. When leaders treat this as natural rather than problematic, burnout decreases and creativity rises.
This rhythm-based lens echoes what biology already teaches: systems that pulse, pause, and renew are the ones that last.
Reclaiming Seasonal Intelligence
The industrial world taught us to override nature’s timing, but the cost has been stress, disconnection, and exhaustion. The opportunity is to relearn what our bodies have always known: that effectiveness follows alignment. When leaders restore that connection, they not only perform better but also model a more sustainable way of living and working.
For me, autumn remains the reminder. The air cools, the light shifts, and I can feel the noise fall away. The signal becomes clear. Nature is whispering what every leader eventually learns: the key to momentum is rhythm, not speed.
Scott Hutcheson, PhD, is a professor at Purdue University and author of Biohacking Leadership: Leveraging the Biology of Behavior to Maximize Impact. He specializes in leadership, team, and organizational performance through the lens of behavioral science and human ecosystems.
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