Effect of Age and Refractive Error on the Melanopsin Mediated Post-Illumination Pupil Response (PIPR)

Adhikari, Prakash; Pearson, Candice A.; Anderson, Alexandra M.; Zele, Andrew J.; Feigl, Beatrix

doi:10.1038/srep17610

Cited by 71 publications

(124 citation statements)

References 45 publications

(66 reference statements)

Supporting

Mentioning

107

Contrasting

Unclassified

Order By: Relevance

“…The data were fitted with linear and exponential models Zele et al 2011) and analyzed according to our established protocols (Adhikari et al 2015b). To control for individual differences in resting pupil diameter, all data are reported as a percentage of the resting baseline pupil diameter (average pupil diameter during 5 s pre-stimulus period) (Adhikari et al 2015a;Adhikari et al 2015b); a larger percentage value indicates smaller constriction amplitude. The PIPR was quantified at six seconds after light stimulus offset (Park et al 2011).…”

Section: Resultsmentioning

confidence: 99%

“…To assess ipRGC function we measured the melanopsin mediated PIPR using customized paradigms developed in our laboratory (Adhikari, Pearson, Anderson, Zele & Feigl 2015a;Adhikari et al 2015b;Feigl et al 2011b;Maynard et al 2015) with high irradiance stimuli designed for use with the RAPDx pupillographer (Konan Medical USA, Inc., Irvine, CA). IpRGCs produce a sustained pupil constriction after offset of short wavelength light known as the post-illumination pupil response (PIPR) (Gamlin et al 2007;Kawasaki & Kardon 2007;Markwell et al 2010), which is absent with presentation of long-wavelength stimuli that have low melanopsin excitation.…”

Section: Pupillometrymentioning

confidence: 99%

“…Furthermore, ipRGC function is robust to ageing (Adhikari et al 2015a;Kankipati et al 2010), with one study showing an enhanced response to high irradiance short wavelength light associated with advancing age (Herbst et al 2012). …”

mentioning

confidence: 99%

See 2 more Smart Citations

Image and Non-Image Forming Melanopsin Function in Age-Related Macular Degeneration

Maynard¹

View full text Add to dashboard Cite

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Pupillometrymentioning

confidence: 99%

See 1 more Smart Citation

Image and Non-Image Forming Melanopsin Function in Age-Related Macular Degeneration

Maynard¹

View full text Add to dashboard Cite

show abstract

“…Hence, a constant retinal irradiance cannot be achieved under a closed-loop condition without the use of pharmacological pupil dilation (Loewenfeld et al, 1993). Since, a Newtonian view pupillometer projects a divergent beam under a closedloop condition, preclinical changes in the pupil responses may be harder to detect given the controlled retinal illumination can only be achieved with a pharmacological dilated pupil that allows for the measurement of the largest consensual pupillary response (Adhikari, Pearson, Anderson, Zele, & Feigl, 2015a). An open-loop condition allows a complete entry of the light into the eye without iris shading (Loewenfeld et al, 1993) and can be achieved by using a Maxwellian view system (Loewenfeld et al, 1993) that focuses the light beam on a small area of the pupil to ensure the complete entry of the light irrespective of the pupil size (Westheimer, 1966).…”

Section: Figurementioning

confidence: 99%

An Evaluation of Melanopsin Function and Light Exposure in Depressive Disorders

Ojha¹

View full text Add to dashboard Cite

Aberrant light exposure causes depression in animals through a pathway involving the recently discovered intrinsically photosensitive Retinal Ganglion Cells (ipRGCs). The photopigment melanopsin expressed in ipRGCs encodes irradiance to signal to the nonimage-forming centres of the brain, including the suprachiasmatic nucleus (SCN) for circadian photoentrainment and the olivary pretectal nucleus (OPN) to control the pupil light reflex. Mouse models have further identified ipRGC projections to the brain nuclei that regulate mood and behaviour. In humans, the post-illumination pupil response (PIPR), a sustained pupillary constriction after light offset, is used as a direct and non-invasive biomarker of ipRGC function.The PIPR amplitude is reduced in humans with seasonal affective disorder (SAD) that shows a seasonal variation in depressive episodes with a peak manifestation in winter when the solar light exposure is low, but a recent study including patients with non-seasonal depressive disorder did not detect ipRGC dysfunction. Moreover, neither study measured the ambient light exposure levels in patients with depression for comparison to healthy individuals without depression. The knowledge of the role of light coding cells (ipRGCs) in major depressive disorder (MDD) is incomplete unless the relationship between ambient light exposure levels and melanopsin function is evaluated. This study aims to measure the environmental light exposure levels and their relationship with melanopsin-mediated PIPR in non-seasonal depression. It is hypothesised that the patients with non-seasonal depression are exposed to low light levels and this is associated with impaired melanopsin function.A sample of 22 adults was recruited, including people with non-seasonal depression (n = 8, median age: 35 years) and healthy age-matched controls (n = 14, median age: 29 years).The presence of a DSM-IV MDD was assessed using the Mini International Neuropsychiatry ii Interview (MINI 6). The severity of depression symptoms was assessed with the Beck Depression Inventory (BDI-II). Individuals with recurrent MDD assessed with the MINI and a positive screen on the Seasonal Pattern Assessment Questionnaire and the Hamilton Depression Rating Scale-SAD (HDRS-SAD) were excluded as SAD. Both groups had visual acuity ≥ 6/6, normal colour vision and intraocular pressure (IOP) ≤ 21 mmHg, no corneal and lenticular opacities and normal retinae and optic discs. The ipRGC-mediated PIPR was measured using a short duration (1 s) high irradiance (15.5 log quanta.cm -2 .s -1 ) short wavelength (blue appearing) light stimulus with a custom built Maxwellian view pupillometer. Light exposure levels, sleep-wake times and sleep efficiency were determined over 2 weeks with an ambulatory light sensor device (Geneactive).The mean daily light exposure levels were similar between the groups and there were no statistically significant differences between the groups for light exposure levels as a function of clock hours, nor in the total number of minutes of exposu...

show abstract

“…Hence, it has been suggested that melatonin may play a role in eye growth and development, and could be involved in the regulation of diurnal rhythms associated with ocular growth. However, a recent cross-sectional study on healthy adult humans (age range: 21 -70 years) found that melanopsin mediated pupil responses were not significantly different between emmetropes and myopes (Adhikari et al, 2015). Further research is required to understand the relationship between habitual light exposure and diurnal rhythms and eye growth, and to understand the relationship between diurnal rhythms and longer-term eye growth in humans.…”

mentioning

confidence: 99%

The Influence of Light Exposure and Seasonal Changes on Short-Term and Longer-Term Changes in Axial Length of the Human Eye

Ulaganathan¹

View full text Add to dashboard Cite

It is widely accepted that environmental factors play a significant role in regulating eye growth and myopia development. There is also considerable evidence that ambient light exposure is an important environmental risk factor associated with eye growth in children, however, the underlying mechanism remains unclear. Furthermore, animal studies have shown that diurnal variations in ocular components appear to be involved in the mechanisms controlling eye growth. Animal studies also suggest that altering light exposure disrupts normal diurnal variations and can lead to the development of refractive errors. Despite this evidence, the exact role of light exposure and ocular diurnal rhythms in the regulation of human eye growth, and the interaction between these factors is not well understood. Myopia development and progression have been widely documented in young adults and typically occurs due to axial elongation, but there has been limited research examining the potential impact of ambient light exposure upon eye growth and myopia development and progression in young adults.Therefore, this research examined the habitual light exposure patterns in a population of young adult emmetropes and progressing myopes using objective techniques, and assessed the influence of light exposure upon daily axial length variations and longitudinal axial eye growth in this population. The potential association between daily axial length fluctuations and longer-term changes in axial length was also explored.Since there is no consensus on the optimal sampling strategy required for capturing personal objective light exposure measurements, in the first study, we systematically examined the impact of different measurement durations and measurement frequencies upon objective light exposure measures, in order to determine the optimal sampling strategy to reliably capture habitual light exposure patterns of both children (Age: 11 to vi The influence of light exposure and seasons upon the axial length changes in humans 15 years) and young adults (Age: 18 to 30 years). Ambient light exposure data were obtained using a wrist-worn light sensor (Actiwatch 2), which was configured to measure instantaneous light levels every 30 seconds, 24 hours a day for a period of 14 consecutive days in children (n = 30) and young adults (n = 31). Daily time exposed to bright outdoor (>1000 lux) light levels was derived from the raw 14 days of data with 30 second sampling, and was subsequently derived from data re-sampled from 12, 10, 8, 6, 4 and 2 randomly selected measurement days using 1, 2, 3, 4, 5 and 10 minute sampling rates. Calculating daily outdoor light exposure time using a lower number of days and coarser sampling frequencies did not significantly alter the mean time spent in bright (outdoor) light. However, a significant increase in measurement variability occurred for outdoor light exposure derived from less than 8 days and from 3 minutes or coarser measurement frequencies in adults, and from less than 8 days and from 4 minutes or coarser...

show abstract

Effect of Age and Refractive Error on the Melanopsin Mediated Post-Illumination Pupil Response (PIPR)

Cited by 71 publications

References 45 publications

Image and Non-Image Forming Melanopsin Function in Age-Related Macular Degeneration

Image and Non-Image Forming Melanopsin Function in Age-Related Macular Degeneration

An Evaluation of Melanopsin Function and Light Exposure in Depressive Disorders

The Influence of Light Exposure and Seasonal Changes on Short-Term and Longer-Term Changes in Axial Length of the Human Eye

Contact Info

Product

Resources

About