Key Observations About Circannual Rhythms
- Light as a Driver:C hanges in daylight exposure across seasons influence melatonin and serotonin, affecting sleep, mood, and energy.
- Temperature’s Role: Warmer temperatures in spring/summer increase activity levels, while cooler temperatures in autumn/winter promote conservation.
- Mood Variability: Mood and motivation peak in spring and summer, tapering in fall, and reaching their lowest in winter.
- Cognitive Cycles:
Spring/Summer: Best for creativity, productivity, and social engagement.
Fall/Winter: Best for planning, reflection, and restoration.
Winter: Conservation and Restoration
Winter Solstice – Start of Winter: December 21st
Spring Equinox – End of Winter: March 20th
Duration: 89 days
exact starts, ends, and durations will vary based on time zone, year, and hemisphere
Neurotransmitters:
- Serotonin: Declines, contributing to low mood in some individuals (SAD).
- Dopamine: Lower levels reduce motivation and reward-seeking behavior.
- GABA: Elevated during restorative activities, promoting relaxation.
Hormones:
- Melatonin: Highest levels, contributing to increased sleepiness and longer nights.
- Cortisol: Morning levels may decrease slightly, leading to slower energy start.
- Thyroid Hormones: May fluctuate, affecting metabolism and energy.
Mood & Energy:
- Reflective, inward-focused moods.
- Energy conservation and potential lethargy.
Cognitive Abilities:
- Reduced multitasking and innovation but improved deep focus on singular tasks.
- Best time for introspection and slow, steady progress.
Physical States:
- Reduced physical activity; metabolism slows slightly.
- Immune system may weaken without proper care (e.g., Vitamin D supplementation).
Best Activities:
Restorative practices (e.g., yoga, meditation), reading, goal-setting for spring.
Spring: Awakening and Renewal
Spring Equinox – Start of Spring: March 20th
Summer Solstice – End of Spring: June 21st
Duration: 93 day
exact starts, ends, and durations will vary based on time zone, year, and hemisphere
Neurotransmitters:
- Serotonin: Gradually increases as daylight lengthens, improving mood and energy.
- Dopamine: Peaks, enhancing motivation, creativity, and goal-directed behaviors.
- Endorphins: Increased physical activity and outdoor exposure boost endorphins.
Hormones:
- Melatonin: Decreases with longer days, supporting wakefulness.
- Cortisol: Stabilizes, enhancing energy and reducing winter fatigue.
- Testosterone: Increases in both sexes, linked to energy, libido, and vitality.
Mood & Energy:
- Rising energy levels, optimism, and social engagement.
- Mood disorders like Seasonal Affective Disorder (SAD) begin to improve.
Cognitive Abilities:
- Increased focus, creativity, and willingness to take on new challenges.
Physical States:
- Improved endurance and recovery as temperatures moderate.
- Immune system may weaken without proper care (e.g., Vitamin D supplementation).
Best Activities:
Goal-setting, creative projects, outdoor activities, and socializing.
Summer: Peak Energy and Activity
Summer Solstice – Start of Summer: June 21st
Autumnal Equinox – End of Summer: September 22nd
Duration: 92 days
exact starts, ends, and durations will vary based on time zone, year, and hemisphere
Neurotransmitters:
- Serotonin: Declines, contributing to low mood in some individuals (SAD).
- Dopamine: Lower levels reduce motivation and reward-seeking behavior.
- GABA: Elevated during restorative activities, promoting relaxation.
Hormones:
- Melatonin: Highest levels, contributing to increased sleepiness and longer nights.
- Cortisol: Morning levels may decrease slightly, leading to slower energy start.
- Thyroid Hormones: May fluctuate, affecting metabolism and energy.
Mood & Energy:
- High energy, social engagement, and adventurousness.
- Risk of burnout or overstimulation if overcommitted.
Cognitive Abilities:
- Strong focus and productivity in the morning, with creativity peaking later in the day.
- Reduced sleep may affect memory consolidation
Physical States:
- Improved strength and endurance, with a tendency for more physical activity.
Best Activities:
Travel, outdoor sports, high-energy projects, and social gatherings.
Autumn: Reflection and Transition
Autumnal Equinox – Start of Autumn: September 22nd
Winter Solstice – End of Autumn: December 21st
Duration: 91 days
exact starts, ends, and durations will vary based on time zone, year, and hemisphere
Neurotransmitters:
- Serotonin: Gradually declines as daylight decreases, leading to reflective and introspective moods.
- Dopamine: Levels taper, reducing novelty-seeking behavior.
- Norepinephrine: Stable, helping maintain focus and preparedness.
Hormones:
- Melatonin: Increases as days shorten, promoting earlier sleep.
- Cortisol: Slightly lower than summer, reducing physical activity.
- Progesterone & Estrogen: Begin shifting, affecting mood and energy (particularly in women).
Mood & Energy:
- A mix of gratitude, nostalgia, and introspection.
- Energy levels moderate; some may experience low mood as daylight decreases.
Cognitive Abilities:
- Strong analytical thinking and decision-making as focus shifts inward.
- Best time for planning and organizing.
Physical States:
- Reduced physical activity; metabolism slows slightly.
- Immune system may weaken without proper care (e.g., Vitamin D supplementation).
Best Activities:
Goal reviews, journaling, creative reflection, and organizing for the future.
