Lighting and Executive Function in Neurodivergence

Introduction:

With rising numbers of adults seeking neurodivergence assessments, it is increasingly urgent to consider what this means for designers.

Although designing for neurodivergence can sometimes be seen as confusing or complicated, many solutions are straightforward and benefit everyone. By looking at circadian rhythm and its effects, I will discuss common neurodivergent triggers, the potential benefits, and some simple solutions.

What is Neurodivergence?

The term neurodivergence covers a wide range of neurological or developmental conditions, where brain function differs from what is considered typical.

Conditions such as Autism, ADHD, Dyslexia, Dyspraxia, and others are included under this term. Neurodivergence is not a disability, but rather a different way of thinking and processing information.

Every neurodivergent individual experience a unique set of symptoms and challenges. These can include difficulty focusing, sensory sensitivity, attention regulation, time blindness, and fidgeting. Triggers vary widely and may include lighting, noise, temperature, or lack of structure. These can also lead to physical reactions such as Migraines and physical discomfort.

This is only a simplified overview, but the key takeaway is this: never assume that a neurodivergent individual’s challenges are the same as another’s.

What is circadian rhythm?

The human body’s natural circadian rhythm is a roughly 24-hour cycle that regulates sleep, alertness, hormone production, and other biological processes. It is strongly influenced by natural lighting and temperature.

As our bodies respond to natural sunlight changes throughout the day, light cues directly affect the brain’s production of serotonin and dopamine. Cool, bluish light in the morning and midday boosts alertness, while warmer, amber light in the evening encourages relaxation and sleep.

Proper circadian alignment is linked to a lower risk of metabolic disorders, cardiovascular issues, and depression. It also supports healthy hormonal cycles, appetite regulation, and immune function. However, artificial lighting in offices, schools, hotels, and homes can easily disrupt this rhythm.

Key Design focus areas:

1. Colour temperature

• Morning and daylight: cooler light – 5000k to 6500k – helps boost alertness.
• Evening and Night: warmer light – 2200k to 3000k – prompt relaxation.

2. Brightness/Ideal Lux levels

• Daylight: 500-1000 lux
• Evening: 50-300 lux

 

3. Timing & Controls

• The lighting needs to follow the natural arc of the day. Transitioning between the colour temperatures and lux levels smoothly.
• Consistency is key. Automated controls can reduce human error and don’t require day to day attention.

4. Distribution & Placement

• Indirect or Diffused lighting reduces glare without losing the desired output.
• The correct placement throughout the space to optimise the space without overwhelming it.

How it benefits neurodivergent people

For neurodivergent individuals, common triggers in office spaces include lighting, noise, visual clutter, and temperature shifts. These can cause sensory overload, making it difficult to process information, prioritize, and focus. Here, lighting design is often about sensory comfort + structured cues to help manage energy and prevent overwhelm.

Neurodivergent individuals may also struggle with dopamine and serotonin regulation—hormones directly tied to motivation, focus, mood, and sensory processing.

By incorporating circadian lighting, we can create lighting cues that better support natural rhythms, balance symptoms, and reduce triggers.

How it benefits neurotypical people

For neurotypical individuals, lighting is more about performance optimization and health maintenance.

Circadian lighting can:

• Boost alertness during afternoon dips
• Offset low mood and fatigue
• Improve overall office atmosphere by creating a more inviting space
• Reduce the effects of Seasonal Affective Disorder (SAD), especially in winter

Solution – Control Options:

1. Daylight Sensor-Integrated Controls
   • Adjust automatically to exterior lighting changes throughout the day and seasons
   • Best for hospitals, schools, high-performance offices
2. Wired/Digital Control Systems
   • Systems like DALI-2, DMX, KNX
   • Best for hospitals, schools, corporate buildings
   • Often integrated with building management systems (BMS)
3. Wireless Control Systems
   • Options include ZigBee, Bluetooth, Wi-Fi
   • Fixtures controlled wirelessly or via apps
   • Best for offices, small healthcare settings, retrofits
4. Smart Controls (stand-alone)
   • Examples: Casambi app control, smart bulbs
   • Best for small offices, homes, and wellness spaces

Conclusion:

Both neurotypical and neurodivergent individuals benefit from better sleep and circadian stability, though the benefits can differ. Each neurodivergent person has unique symptoms, triggers, and reactions.

Circadian lighting can:

• Improve sensory comfort
• Reduce overstimulation
• Support focus and cognitive bandwidth

For neurotypical individuals, it optimizes natural focus, energy, and mood stability, while also reducing SAD symptoms and creating healthier environments.

Although the exact benefits may vary, the evidence is clear: circadian lighting supports both neurodivergent and neurotypical individuals across a wide range of settings.