¿Qué impacto tiene exponernos a la luz artificial sobre nuestra fisiología y estado psicológico?

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¿Qué impacto tiene exponernos a la luz artificial sobre nuestra fisiología y estado psicológico?

SEPEX, SEPNECA and AIP experimental Conference. Madrid, 4 July 2018

Ángel Correa

Beatriz Rodríguez-Morilla Antonio Barba

Francisca Padilla

Juan Antonio Madrid (UMU)

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2

•

Natural light/darkness cycle entrains our circadian rhythms (sleep/wake)

•

However, we increasingly expend more time indoors (daylight -> electrical light)

•

Impact on health?

(3)

THE PANACEA:

Improved Visual Acuity Reduced Fatigue

Fewer Dental Caries

Accelerated Maturation

Improved Neural Functioning Reduced Seasonal Depression Reduced Bulimia

Reduced Hyperactivity

Greater School Achievement Improved Attendance

Greater Attentiveness Improved Mood

1973

Full spectrum

fluorescent lamps = health

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THE PANACEA:

Improved Visual Acuity Reduced Fatigue

Fewer Dental Caries

Accelerated Maturation

Improved Neural Functioning Reduced Seasonal Depression Reduced Bulimia

Reduced Hyperactivity

Greater School Achievement Improved Attendance

Greater Attentiveness Improved Mood

1973

Only a full spectrum of

natural light could promote full health in plants, animals, and humans

1986

“Health Fraud Notice”: absence of

sound scientific evidence in support

of the health claims made in the

lamp’s labelling

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5

Night shift work = probable carcinogen (circadian disruption; WHO).

Artificial light at night, circadian disruption and breast and prostate cancers

2007

2018

New photoreceptor (ipRGC): “blue” wavelength light resets the circadian clock (Berson et al., 2002)

2002

Nobel Prize in Physics for the invention of the blue LED

2014 2005

Blue light at night boosts alertness (melatonin,

thermophysiology, heart rate; Cajochen et al., 2005)

full spectrum -> blue light

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6

Night shift work = probable carcinogen (circadian disruption; WHO).

Artificial light at night, circadian disruption and breast and prostate cancers

2007

2018

New photoreceptor (ipRGC): “blue” wavelength light resets the circadian clock (Berson et al., 2002)

2002

Nobel Prize in Physics for the invention of the blue LED

2014 2005

Blue light at night boosts alertness (melatonin,

thermophysiology, heart rate; Cajochen et al., 2005)

Neurocognitive effects of light

1. Beyond alertness

2. Ecological conditions

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Subjective Physiological Behavioural

Sleepiness (KSS)

Mood

(VAS, PANAS)

Mental effort

Visual confort

Distal temperature Proximal

Distal-Proximal Gradient (DPG)

Vigilance Tasks (PVT, Driving, SART)

Reaction time

Accuracy

Inhibitory control

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Subjective Physiological Behavioural Sleepiness

(KSS)

Mood

(VAS, PANAS)

Mental effort

Visual confort

Distal temperature Proximal

Distal-Proximal Gradient (DPG)

PVT, Driving, SART

Reaction time

Accuracy

Inhibitory control

Pre-test ADAPTATION

TO LIGHT TASK Post-test

10 min 20 min 20 - 60 min 10 min

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10

Study N Design Task

1 Rodriguez-Morilla

et al. 2017 36

Blue Dim Orange

Simulated Driving

2 Rodriguez-Morilla

et al. 2018 17 Blue vs. Dim (within) Simulated Driving

3 Barba et al. 15

Blue Dim Orange

SART

4 Correa et al.

2016 24 Blue vs. Dim (within) SART

5 Barba et al. 45 Blue vs. Dim (within) PVT

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11

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12

•

no effects on subjective somnolence or mood

•

enhanced arousal (lower temperature gradient)

•

facilitated fast responding, but…

•

… impaired driving accuracy

Blue-enriched white light

Differential effects as a function of specific task demands?

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13

50 ms

1150 ms

or until response Error

No-go

Error

Go

No-go

1200 ms

3 3"

2"

7"

Condition Index Process

GO RT automatic

NOGO accuracy controlled

Sustained Attention to Response Task (SART)

Robertson et al, 1997

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14

Condition Index Process

GO RT automatic

NOGO accuracy controlled

f a s t e r ‘ a u t o m a t i c ’ responding (go trials)

no effect on inhibitory control

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15

Study N Somno-

lence Mood Arousal (DPG)

Response speed

Task accuracy

Rodriguez- Morilla et

al. 2017 36

x x

al. 2018 17

x x

Barba et

al. 15

x x x x

Correa et

al. 2016 24

x x x

Barba et

al. 45

x x

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16

Study N Somno-

lence Mood Arousal (DPG)

Response speed

Task accuracy

al. 2017 36

x x

al. 2018 17

x x

Barba et

al. 15

x x x x

Correa et

al. 2016 24

x x x

Barba et

al. 45

x x

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Right skewed p-curve = presence of eviden6al value

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p-curve does not indicate eviden/al value Lighting effects on Reaction Time