Circadian rhythm and light

قَالَ مُوسَىٰٓ أَتَقُولُونَ لِلۡحَقِّ لَمَّا جَآءَكُمۡۖ أَسِحۡرٌ هَٰذَا وَلَا يُفۡلِحُ ٱلسَّٰحِرُونَ

Moses said, ‘Is this what you say about the Truth when it comes to you? Is this sorcery? Sorcerers never prosper.’

فَلَمَّا جَآءَ ٱلسَّحَرَةُ قَالَ لَهُم مُّوسَىٰٓ أَلۡقُواْ مَآ أَنتُم مُّلۡقُونَ

When the sorcerers came, Moses said to them, ‘Throw down whatever you have.’

فَلَمَّآ أَلۡقَوۡاْ قَالَ مُوسَىٰ مَا جِئۡتُم بِهِ ٱلسِّحۡرُۖ إِنَّ ٱللَّهَ سَيُبۡطِلُهُۥٓ إِنَّ ٱللَّهَ لَا يُصۡلِحُ عَمَلَ ٱلۡمُفۡسِدِينَ

When they did so, Moses said, ‘Everything you have brought is sorcery and God will show it to be false. God does not make the work of mischief-makers right

وَٱتَّبَعُواْ مَا تَتۡلُواْ ٱلشَّيَٰطِينُ عَلَىٰ مُلۡكِ سُلَيۡمَٰنَۖ وَمَا كَفَرَ سُلَيۡمَٰنُ وَلَٰكِنَّ ٱلشَّيَٰطِينَ كَفَرُواْ يُعَلِّمُونَ ٱلنَّاسَ ٱلسِّحۡرَ وَمَآ أُنزِلَ عَلَى ٱلۡمَلَكَيۡنِ بِبَابِلَ هَٰرُوتَ وَمَٰرُوتَۚ وَمَا يُعَلِّمَانِ مِنۡ أَحَدٍ حَتَّىٰ يَقُولَآ إِنَّمَا نَحۡنُ فِتۡنَةࣱ فَلَا تَكۡفُرۡۖ فَيَتَعَلَّمُونَ مِنۡهُمَا مَا يُفَرِّقُونَ بِهِۦ بَيۡنَ ٱلۡمَرۡءِ وَزَوۡجِهِۦۚ وَمَا هُم بِضَآرِّينَ بِهِۦ مِنۡ أَحَدٍ إِلَّا بِإِذۡنِ ٱللَّهِۚ وَيَتَعَلَّمُونَ مَا يَضُرُّهُمۡ وَلَا يَنفَعُهُمۡۚ وَلَقَدۡ عَلِمُواْ لَمَنِ ٱشۡتَرَىٰهُ مَا لَهُۥ فِي ٱلۡأٓخِرَةِ مِنۡ خَلَٰقࣲۚ وَلَبِئۡسَ مَا شَرَوۡاْ بِهِۦٓ أَنفُسَهُمۡۚ لَوۡ كَانُواْ يَعۡلَمُونَ

and followed what the evil ones had fabricated about the Kingdom of Solomon instead. Not that Solomon himself was a disbeliever; it was the evil ones who were disbelievers. They taught people witchcraft and what was revealed in Babylon to the two angels Harut and Marut. Yet these two never taught anyone without first warning him, ‘We are sent only to tempt- do not disbelieve.’ From these two, they learned what can cause discord between man and wife, although they harm no one with it except by God’s leave. They learned what harmed them, not what benefited them, knowing full well that whoever gained [this knowledge] would lose any share in the Hereafter. Evil indeed is the [price] for which they sold their souls, if only they knew

وَجَآءَ ٱلسَّحَرَةُ فِرۡعَوۡنَ قَالُوٓاْ إِنَّ لَنَا لَأَجۡرًا إِن كُنَّا نَحۡنُ ٱلۡغَٰلِبِينَ

The sorcerers came to Pharaoh and said, ‘Shall we be rewarded if we win?’

وَأُلۡقِيَ ٱلسَّحَرَةُ سَٰجِدِينَ

The sorcerers fell to their knees

(And follow that which the devils falsely related against the kingdom of Solomon�) [2:102]. Muhammad ibn 'Abd al-'Aziz al-Qantari informed us> Abu'l-Fadl al-Haddadi> Abu Yazid al-Khalidi> Ishaq ibn Ibrahim> Jarir> Husayn ibn 'Abd al-Rahman> 'Imran ibn al-Harith who said: �Once as we were sitting with Ibn 'Abbas when he said: 'The devils used to eavesdrop on heaven. One of them would bring a word of truth from therein, and when he is trusted for telling the truth, he would add to it seventy lies with which he earns the hearts of people. When Solomon came to know about it, he took it and buried it beneath his throne. When he died, a devil stood in the street and said: 'Shall I guide you to Solomon's guarded treasure, the like of which he does not have?' They said: 'Yes, do'. He said: 'It is under his throne; go and unearth it'. They said: 'This is magic'. Different nations then copied it f

And they follow wa’ttaba‘ū is a supplement to nabadha ‘it cast away’ what the devils used to relate during the time of Solomon’s kingdom in the way of sorcery it is said that they the devils buried these books of sorcery underneath his throne when his kingdom was taken from him; it is also said that they used to listen stealthily and add fabrications to what they heard and then pass it on to the priests who would compile it in books; this would be disseminated and rumours spread that the jinn had knowledge of the Unseen. Solomon gathered these books and buried them. When he died the devils showed people where these books were and the latter brought them out and found that they contained sorcery and said ‘Your kingdom was only thanks to what is in here’; they then took to learning them and rejected the Scriptures of their prophets. In order to demonstrate Solomon’s innocence and in repudi

And the sorcerers came to Pharaoh saying ‘Surely a-inna read pronouncing both hamzas or by not pronouncing the second one but inserting an alif between the two in both cases there will be a wage for us if we are the victors?’

And the sorcerers fell down in prostration.

And so the sorcerers came to Fir'awn. They said: "Indeed there will be a (good) reward for us if we are the victors. (113)He said: "Yes, and moreover you will (in that case) be of the nearest (to me). (114) The Magicians convene and change Their Ropes into Snakes before Musa Allah describes the conversation that took place between Fir'awn and the magicians he collected to defeat Musa, peace be upon him. Fir'awn told them that he will reward them and give them tremendous provisions. He made them hope in acquiring what they wished for and to make them among his private audience and best associates. When they were assured of the cursed Fir'awn's promises,

And We revealed to Musa (saying): "Throw your stick," and behold! It swallowed up straight away all the falsehood which they showed (117)Thus truth was confirmed, and all that they did was made of no effect (118)So they were defeated there and returned disgraced (119)And the sorcerers fell down prostrate (120)They said: "We believe in the Lord of all that exists (121)"The Lord of Musa and Harun. (122) Musa defeats the Magicians, Who believe in Him Allah states that at that tremendous moment, in which Allah differentiated between Truth and Falsehood, He sent a revelation to His servant and Messenger Musa, peace be upon him, ordering him to throw the stick that he held in his right hand, فَإِذَا هِيَ تَلْقَفُ (It swallowed straight away) and devoured, مَا يَأْفِكُونَ (all the falsehood which they showed.) the magic that they caused the illusion with, of magic with which they caused m

حَدَّثَنَا أَبُو نُعَيْمٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنِ الأَسْوَدِ، قَالَ سَمِعْتُ جُنْدَبًا، يَقُولُ اشْتَكَى النَّبِيُّ صلى الله عليه وسلم فَلَمْ يَقُمْ لَيْلَةً أَوْ لَيْلَتَيْنِ‏.‏

Narrated Jundab:The Prophet (ﷺ) became sick and did not get up (for Tahajjud prayer) for a night or two

حَدَّثَنَا ابْنُ مُقَاتِلٍ، أَخْبَرَنَا عَبْدُ اللَّهِ، أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ هِنْدٍ بِنْتِ الْحَارِثِ، عَنْ أُمِّ سَلَمَةَ ـ رضى الله عنها ـ أَنَّ النَّبِيَّ صلى الله عليه وسلم اسْتَيْقَظَ لَيْلَةً فَقَالَ ‏ "‏ سُبْحَانَ اللَّهِ مَاذَا أُنْزِلَ اللَّيْلَةَ مِنَ الْفِتْنَةِ، مَاذَا أُنْزِلَ مِنَ الْخَزَائِنِ مَنْ يُوقِظُ صَوَاحِبَ الْحُجُرَاتِ، يَا رُبَّ كَاسِيَةٍ فِي الدُّنْيَا عَارِيَةٍ فِي الآخِرَةِ ‏"‏‏.‏

Narrated Um Salama:One night the Prophet (ﷺ) got up and said, "Subhan Allah! How many afflictions Allah has revealed tonight and how many treasures have been sent down (disclosed). Go and wake the sleeping lady occupants of these dwellings up (for prayers), perhaps a well dressed in this world may be naked in the Hereafter

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، قَالَ قَرَأْتُ عَلَى مَالِكٍ عَنِ ابْنِ شِهَابٍ، أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ، أَخَّرَ الصَّلاَةَ يَوْمًا، فَدَخَلَ عَلَيْهِ عُرْوَةُ بْنُ الزُّبَيْرِ، فَأَخْبَرَهُ أَنَّ الْمُغِيرَةَ بْنَ شُعْبَةَ أَخَّرَ الصَّلاَةَ يَوْمًا وَهْوَ بِالْعِرَاقِ، فَدَخَلَ عَلَيْهِ أَبُو مَسْعُودٍ الأَنْصَارِيُّ فَقَالَ مَا هَذَا يَا مُغِيرَةُ أَلَيْسَ قَدْ عَلِمْتَ أَنَّ جِبْرِيلَ نَزَلَ فَصَلَّى، فَصَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم ثُمَّ صَلَّى فَصَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم ثُمَّ صَلَّى فَصَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم ثُمَّ صَلَّى فَصَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم ثُمَّ صَلَّى فَصَلَّى رَسُولُ اللَّهِ صلى الله عليه وسلم ثُمَّ قَالَ ‏ "‏ بِهَذَا أُمِرْتُ ‏"‏‏.‏ فَقَالَ عُمَرُ لِعُرْوَةَ اعْلَمْ مَا تُحَدِّثُ أَوَإِنَّ جِبْرِيلَ هُوَ أَقَامَ لِرَسُولِ اللَّهِ صلى الله عليه وسلم وَقْتَ الصَّلاَةِ‏.‏ قَالَ عُرْوَةُ كَذَلِكَ كَانَ بَشِيرُ بْنُ أَبِي مَسْعُودٍ يُحَدِّثُ عَنْ أَبِيهِ‏.‏ قَالَ عُرْوَةُ وَلَقَدْ حَدَّثَتْنِي عَائِشَةُ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يُصَلِّي الْعَصْرَ، وَالشَّمْسُ فِي حُجْرَتِهَا قَبْلَ أَنْ تَظْهَرَ‏.‏

Narrated Ibn Shihab:Once `Umar bin `Abdul `Aziz delayed the prayer and `Urwa bin Az-Zubair went to him and said, "Once in 'Iraq, Al-Mughira bin Shu`ba delayed his prayers and Abi Mas`ud Al-Ansari went to him and said, 'O Mughira! What is this? Don't you know that once Gabriel came and offered the prayer (Fajr prayer) and Allah's Messenger (ﷺ) prayed too, then he prayed again (Zuhr prayer) and so did Allah's Apostle and again he prayed (`Asr prayers and Allah's Messenger (ﷺ) did the same; again he prayed (Maghrib-prayer) and so did Allah's Messenger (ﷺ) and again prayed (`Isha prayer) and so did Allah's Apostle and (Gabriel) said, 'I was ordered to do so (to demonstrate the prayers prescribed to you)?'" `Umar (bin `Abdul `Aziz) said to `Urwa, "Be sure of what you Say. Did Gabriel lead Allah's Messenger (ﷺ) at the stated times of the prayers?" `Urwa replied, "Bashir bin Abi Mas`ud narrated like this on the authority of his father." `Urwa added, "Aisha told me that Allah's Messenger (ﷺ) used to pray `Asr prayer when the sunshine was still inside her residence (during the early time of `Asr)

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا عَبَّادٌ ـ هُوَ ابْنُ عَبَّادٍ ـ عَنْ أَبِي جَمْرَةَ، عَنِ ابْنِ عَبَّاسٍ، قَالَ قَدِمَ وَفْدُ عَبْدِ الْقَيْسِ عَلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالُوا إِنَّا مِنْ هَذَا الْحَىِّ مِنْ رَبِيعَةَ، وَلَسْنَا نَصِلُ إِلَيْكَ إِلاَّ فِي الشَّهْرِ الْحَرَامِ، فَمُرْنَا بِشَىْءٍ نَأْخُذْهُ عَنْكَ، وَنَدْعُو إِلَيْهِ مَنْ وَرَاءَنَا‏.‏ فَقَالَ ‏ "‏ آمُرُكُمْ بِأَرْبَعٍ، وَأَنْهَاكُمْ عَنْ أَرْبَعٍ الإِيمَانِ بِاللَّهِ ـ ثُمَّ فَسَّرَهَا لَهُمْ شَهَادَةُ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ، وَأَنِّي رَسُولُ اللَّهِ، وَإِقَامُ الصَّلاَةِ، وَإِيتَاءُ الزَّكَاةِ، وَأَنْ تُؤَدُّوا إِلَىَّ خُمُسَ مَا غَنِمْتُمْ، وَأَنْهَى عَنِ الدُّبَّاءِ وَالْحَنْتَمِ وَالْمُقَيَّرِ وَالنَّقِيرِ ‏"‏‏.‏

Narrated Ibn `Abbas:"Once a delegation of `Abdul Qais came to Allah's Messenger (ﷺ) and said, "We belong to such and such branch of the tribe of Rabi'ah and we can only come to you in the sacred months. Order us to do something good so that we may take it from you and also invite to it those whom we have left behind (at home)." So he said, "I order you to do four things and forbid you from four things: To believe in Allah" - and then he explained it to them "to testify that none has the right to be worshipped but Allah and that I am Allah's Messenger (ﷺ), to establish the prayers (at the stated times), to pay the Zakat (obligatory charity), to hand me the Khumus (fifth) if you acquire spoils of war. And I forbid from (using) Dubba, Hantam, Muqaiyyar, and Naqir (all these were utensils used for the preparation of alcoholic drinks)

أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ بْنُ سَعْدٍ، عَنِ ابْنِ شِهَابٍ، أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ، أَخَّرَ الْعَصْرَ شَيْئًا فَقَالَ لَهُ عُرْوَةُ أَمَا إِنَّ جِبْرِيلَ عَلَيْهِ السَّلاَمُ قَدْ نَزَلَ فَصَلَّى أَمَامَ رَسُولِ اللَّهِ صلى الله عليه وسلم ‏.‏ فَقَالَ عُمَرُ اعْلَمْ مَا تَقُولُ يَا عُرْوَةُ ‏.‏ فَقَالَ سَمِعْتُ بَشِيرَ بْنَ أَبِي مَسْعُودٍ يَقُولُ سَمِعْتُ أَبَا مَسْعُودٍ يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ ‏ "‏ نَزَلَ جِبْرِيلُ فَأَمَّنِي فَصَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ‏"‏ ‏.‏ يَحْسُبُ بِأَصَابِعِهِ خَمْسَ صَلَوَاتٍ ‏.‏

It was narrated from Ibn Shihab that 'Umar bin 'Abdul-'Aziz delayed the 'Asr prayer a little. 'Urwah said to him:"Jibril came down and led the Messenger of Allah (ﷺ) in prayer." 'Umar said: "Watch what you are saying, O 'Urwah!" He said: "I heard Bashir bin Abi Mas'ud say: 'I heard Abu Mas'ud say: "I heard the Messenger of Allah (ﷺ) say: 'Jibril came down and led me in prayer, and I prayed with him, then I prayed with him, then I prayed with him, then I prayed with him, then I prayed with him - and he counted off five prayers on his fingers

أَخْبَرَنَا مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، قَالَ حَدَّثَنَا خَالِدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، قَالَ حَدَّثَنَا سَيَّارُ بْنُ سَلاَمَةَ، قَالَ سَمِعْتُ أَبِي يَسْأَلُ أَبَا بَرْزَةَ، عَنْ صَلاَةِ، رَسُولِ اللَّهِ صلى الله عليه وسلم قُلْتُ أَنْتَ سَمِعْتَهُ قَالَ كَمَا أَسْمَعُكَ السَّاعَةَ فَقَالَ سَمِعْتُ أَبِي يَسْأَلُ عَنْ صَلاَةِ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ كَانَ لاَ يُبَالِي بَعْضَ تَأْخِيرِهَا - يَعْنِي الْعِشَاءَ - إِلَى نِصْفِ اللَّيْلِ وَلاَ يُحِبُّ النَّوْمَ قَبْلَهَا وَلاَ الْحَدِيثَ بَعْدَهَا ‏.‏ قَالَ شُعْبَةُ ثُمَّ لَقِيتُهُ بَعْدُ فَسَأَلْتُهُ قَالَ كَانَ يُصَلِّي الظُّهْرَ حِينَ تَزُولُ الشَّمْسُ وَالْعَصْرَ يَذْهَبُ الرَّجُلُ إِلَى أَقْصَى الْمَدِينَةِ وَالشَّمْسُ حَيَّةٌ وَالْمَغْرِبَ لاَ أَدْرِي أَىَّ حِينٍ ذَكَرَ ثُمَّ لَقِيتُهُ بَعْدُ فَسَأَلْتُهُ فَقَالَ وَكَانَ يُصَلِّي الصُّبْحَ فَيَنْصَرِفُ الرَّجُلُ فَيَنْظُرُ إِلَى وَجْهِ جَلِيسِهِ الَّذِي يَعْرِفُهُ فَيَعْرِفُهُ ‏.‏ قَالَ وَكَانَ يَقْرَأُ فِيهَا بِالسِّتِّينَ إِلَى الْمِائَةِ ‏.‏

Shu'bah said:"Sayyar bin Salamah, narrated to us, he said: 'I heard my father ask Abu Barzah about the prayer of the Messenger of Allah (ﷺ).' I said: 'Did you really hear him?' He said: 'As I can hear you now.' He said: 'I heard my father ask about the prayer of the Messenger of Allah (ﷺ).' He said: 'He would not mind if he delayed it - meaning 'Isha' until midnight, and he did not like to sleep before it or speak after it.'" Shu'bah said: "Then I met him later on and asked him. He said: 'He used to pray Zauhr when the sun had passed its zenith, and (he would pray) 'Asr and a man could walk to the farthest point in Al-Madinah and the sun would still be clear and hot. And Maghrib, I do not know the time he mentioned.' After that I met him and asked him, and he said: 'He used to pray Fajr then after the prayer a man could regarding it, sitting next to him, look at the face of someone he knew and he could recognize it.' He said: 'And he used to recite in it between sixty and one hundred (verses)

وعبادته التي هو مشغول بها لا ينتقل إلى غيرها ولا يفتر عنها لا يستكبرون عن عبادته ولا يستحسرون يسبحون الليل والنهار لا يفترون ومفتاح مزيد الدرجات هي الصلوات

وينبغي أن لا ينفصل من طرف عرفة إلا بعد الغروب ليجمع في عرفة بين الليل والنهار وإن أمكنه الوقوف يوم الثامن ساعة عند إمكان الغلط في الهلال فهو الحزم وبه الأمن من الفوات

الباب الأول في فضيلة الأوراد وترتيبها في الليل والنهار

يشير إلى أنه غير متطلع إلى الأوقات بل هو مع الذي يقدر الليل والنهار

فهذا سؤال جاهل ظالم ضال مفرط في الجهل والظلم والضلال لأن خلق الأضداد والمتقابلات هو من كمال الربوبية كالليل والنهار والحر والبرد واللذة والألم والخير والشر والنعيم والجحيم

خلفة لمن أراد أن يذكر أو أراد شكورا} [الفرقان: 62]، أي يخلف أحدهما الآخر ليتدارك في أحدهما ما فات في الآخر. ### $ 2 - بيان عدد أوراد الليل والنهار وترتيبها

Diagnosis of circadian rhythm sleep disorders.: Insomnia and excessive sleepiness are common in the investigation of sleep-disordered breathing. Circadian rhythm sleep disorders are perhaps the most often overlooked conditions in the differential diagnosis of these symptoms. Circadian rhythm sleep disorders manifest as misalignment between the sleep period and the physical/social 24-h environmental cycle. The two most prevalent circadian rhythm sleep disorders are delayed sleep phase (common in adolescents) and advanced sleep phase (common in

Intrinsic circadian period of sighted patients with circadian rhythm sleep disorder, free-running type.: Background: Circadian rhythm sleep disorder, free-running type (FRT), is an intractable sleep disorder in which sleep and wake times progressively delay each day even in normal living environments. This disorder severely affects the social functioning of patients because of periodic nighttime insomnia, excessive daytime sleepiness, and a high rate of comorbid psychiatric disorders. Although abnormal regulation of the biological clock is suspected, the pathophysiology of FRT has yet to be elucida

Identification of a Preliminary Plasma Metabolome-based Biomarker for Circadian Phase in Humans.: Measuring individual circadian phase is important to diagnose and treat circadian rhythm sleep-wake disorders and circadian misalignment, inform chronotherapy, and advance circadian science. Initial findings using blood transcriptomics to predict the circadian phase marker dim-light melatonin onset (DLMO) show promise. Alternatively, there are limited attempts using metabolomics to predict DLMO and no known omics-based biomarkers predict dim-light melatonin offset (DLMOff). We analyzed the human

Home dim light melatonin onsets with measures of compliance in delayed sleep phase disorder.: The dim light melatonin onset (DLMO) assists with the diagnosis and treatment of circadian rhythm sleep disorders. Home DLMOs are attractive for cost savings and convenience, but can be confounded by home lighting and sample timing errors. We developed a home saliva collection kit with objective measures of light exposure and sample timing. We report on our first test of the kit in a clinical population. Thirty-two participants with delayed sleep phase disorder (DSPD; 17 women, aged 18-52 years)

A randomized controlled trial with bright light and melatonin for the treatment of delayed sleep phase disorder: effects on subjective and objective sleepiness and cognitive function.: Delayed sleep phase disorder (DSPD) is a circadian rhythm sleep disorder. Patients with DSPD have problems initiating sleep if they go to bed at a conventional time, and they often have problems waking at desired times. If they rise early in the morning, they usually experience severe sleepiness during morning hours. In the present study, we investigated the short- and long-term effects on measures of subjective and objective sleepiness and cognitive function of bright light and melatonin treatm

Light-induced changes of the circadian clock of humans: increasing duration is more effective than increasing light intensity.: Study objectives: To evaluate the effect of increasing the intensity and/or duration of exposure on light-induced changes in the timing of the circadian clock of humans. Design: Multifactorial randomized controlled trial, between and within subject design Setting: General Clinical Research Center (GCRC) of an academic medical center Participants: 56 healthy young subjects (20-40 years of age) Interventions: Research subjects were admitted for 2 independent stays of 4 nights/3 days for treatment

Physical activity, athletic performance, and recovery: The role of sleep.

Background: Physical activity is widely recognized for its benefits on physical and mental health. However, interactions between sleep, athletic performance, and recovery remain complex and incompletely understood. This narrative review synthesizes recent evidence on the relationships between physical activity, mental health, sleep, and performance, and outlines potential therapeutic perspectives. Methods: We reviewed recent meta-analyses, randomized controlled trials, observational studies, and expert consensus statements addressing physical activity, sleep, mental health, athletic performance, recovery, napping, and circadian factors in both general and athletic populations. Results: Physical activity shows a clear inverse dose-response relationship with depression risk, with even moderate levels conferring significant mental health benefits. Regular physical activity (≥150min/week of …

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Therapeutic role of melatonin in migraine prophylaxis: Is there a link between sleep and migraine?

Melatonin is a ubiquitously distributed molecule that possesses diverse functions. Melatonin plays a key role in the endogenous circadian rhythms of humans via light stimulation in the hypothalamus. In addition, melatonin has roles in the opioid system, the nitric oxide pathway, free radical scavenging, inflammation, and antinociception. Melatonin is nontoxic and relatively safe. Recently, exogenous melatonin has been shown to have significant effects in the treatment of migraine. Further, it has demonstrated efficacy in the treatment of sleep disorders, including insomnia, circadian rhythm sleep-wake disorders, parasomnias, and sleep breathing disorders. Sleep disorders are commonly reported by those who experience migraine, and migraine and sleep disorders have been reported to be closely associated in cross-sectional studies. Longitudinal studies have shown that some sleep disorders a…

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Sleep disturbance as transdiagnostic: consideration of neurobiological mechanisms.

Sleep disturbance is increasingly recognized as an important, but understudied, mechanism in the complex and multi-factorial causation of the symptoms and functional disability associated with psychiatric disorders. This review proposes that it is biologically plausible for sleep disturbance to be mechanistically transdiagnostic. More specifically, we propose that sleep disturbance is aetiologically linked to various forms of psychopathology through: its reciprocal relationship with emotion regulation and its shared/interacting neurobiological substrates in (a) genetics--genes known to be important in the generation and regulation of circadian rhythms have been linked to a range of disorders and (b) dopaminergic and serotonergic function--we review evidence for the interplay between these systems and sleep/circadian biology. The clinical implications include potentially powerful and inex…

matched on Circadian Rhythm (mesh), circadian (text), light exposure (text)

Effect of Repeated Low-Level Red-Light Therapy for Myopia Control in Children: A Multicenter Randomized Controlled Trial.

Purpose: To assess the efficacy and safety of repeated low-level red-light (RLRL) therapy in myopia control in children. Design: Multicenter, randomized, parallel-group, single-blind clinical trial. Participants: Two hundred sixty-four eligible children 8 to 13 years of age with myopia of cycloplegic spherical equivalent refraction (SER) of -1.00 to -5.00 diopters (D), astigmatism of 2.50 D or less, anisometropia of 1.50 D or less, and best-corrected visual acuity (BCVA) of 0.0 logarithm of the minimum angle of resolution or more were enrolled in July and August 2019. Follow-up was completed in September 2020. Methods: Children were assigned randomly to the intervention group (RLRL treatment plus single-vision spectacle [SVS]) and the control group (SVS). The RLRL treatment was provided by a desktop light therapy device that emits red light of 650-nm wavelength at an illuminance level of…

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A clinical allostatic load index is associated with burnout symptoms and hypocortisolemic profiles in healthy workers.

Chronic stress causes stress hormones to strain many biological systems in a process referred to as allostatic load (AL) that is measurable using an index of biomarkers. While the AL framework has been successfully applied in studies of workplace stress, few studies have investigated burnout, a debilitating condition sometimes characterized by blunted stress hormone levels. Using an AL index based on clinical norms, we hypothesized that higher AL indices would be associated with increased chronic stress, burnout symptoms, as well as hypoactive diurnal and reactive stress hormone levels. Fifteen neuroendocrine, immune, metabolic, and cardiovascular biomarkers were collected for 30 healthy participants from various professions and values were transformed into an AL index using clinical norms. Stress reactivity was assessed for salivary cortisol and α-amylase levels in response to the Trier…

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Momentary work worries, marital disclosure, and salivary cortisol among parents of young children.

Objective: To investigate whether worries about work are linked to people's own cortisol levels and their spouses' cortisol levels in everyday life and whether marital factors may moderate these links. Although research has shown that satisfying marriages can buffer the physiological effects of everyday stress, the specific mechanisms through which marriage influences the processing and transmission of stress have not yet been identified. Methods: Thirty-seven healthy married couples completed baseline measures and then provided saliva samples and indicated their worries about work for six times a day from a Saturday morning through a Monday evening. Results: Wives' cortisol levels were associated positively with their own work worries (p = .008) and with their husbands' work worries (p = .006). Husbands' cortisol levels were associated positively only with their own work worries (p = .0…

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Socioeconomic and race/ethnic differences in daily salivary cortisol profiles: the multi-ethnic study of atherosclerosis.

It has often been hypothesized that stress and its biological consequences mediate the relationship between low socioeconomic status (SES) or minority status and poor cardiovascular disease outcomes. The objective of this study was to determine if daily cortisol patterns, a biomarker of the stress response, differ by race/ethnicity and socioeconomic status. Data were collected from 935 Black, White and Hispanic adults age 48-90 years old. Salivary cortisol samples were collected six times per day over 3 days: at awakening, 30min later, at 1000h, noon, 1800h and at bedtime. Blacks and Hispanics had lower levels of wake-up cortisol and less steep early declines, while Blacks had flatter and Hispanics steeper late day declines relative to Whites. Similarly the low socioeconomic status group also had lower levels of wake-up cortisol and less steep decline during the early part of the day. Th…

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Comparing cortisol, stress, and sensory sensitivity in children with autism.

Previously we reported that children with autism show significant variability in cortisol. The current investigation was designed to extend these findings by exploring plausible relationships between cortisol and psychological measures of stress and sensory functioning. Salivary cortisol values for diurnal rhythms and response to stress in children with and without autism were compared to parent-report measures of child stress, the Stress Survey Schedule (SSS), sensory functioning, Short Sensory Profile (SSP), and Parenting Stress Index. In autism, a negative relationship between morning cortisol and the SSS revealed that higher observed symptoms of stress were related to lower cortisol. Lower cortisol is seen in conditions of chronic stress and in social situations characterized by unstable social relationships. Sensory sensitivity painted a more complicated picture, in that some aspect…

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Collaborative coping and daily mood in couples dealing with prostate cancer.

Collaborative coping (i.e., spouses pooling resources and problem solving jointly) may be associated with better daily mood because of heightened perceptions of efficacy in coping with stressful events. The study examined the daily processes of collaborative coping (individuals' perceptions that the spouse collaborated), perceived coping effectiveness (ratings of how well they dealt with the event), and mood (i.e., Positive and Negative Affect Scale) across 14 days in 57 older couples coping with stressors involving the husband's prostate cancer and daily life in general. In hierarchical multivariate linear models, collaborative coping was associated with more positive same-day mood for both husbands and wives and less negative mood for wives only. These associations were partially mediated by heightened perceptions of coping effectiveness. Exploratory analyses revealed that collaborativ…

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Diurnal cortisol decline is related to coronary calcification: CARDIA study.

Objective: Chronic stress may be a risk factor for coronary heart disease and is associated with dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. We tested the hypotheses that two markers of HPA axis dysregulation, elevated average level (area under the curve, adjusted for time awake) and diurnal decline of salivary cortisol, were associated with presence of coronary calcification (CaC). Method: Seven hundred eighteen black and white middle-aged adults enrolled in an ancillary study of Coronary Artery Risk Development in Young Adults provided six salivary cortisol samples throughout one full day and had measurements of CaC. Results: The prevalence of any calcification was low, 8.1% in the participants of the ancillary study, with white men having the highest proportion. Average cortisol did not differentiate groups, means = 2.15 and 2.08. Those with any CaC declined approx…

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Amygdala and ventromedial prefrontal cortex are inversely coupled during regulation of negative affect and predict the diurnal pattern of cortisol secretion among older adults.

Among younger adults, the ability to willfully regulate negative affect, enabling effective responses to stressful experiences, engages regions of prefrontal cortex (PFC) and the amygdala. Because regions of PFC and the amygdala are known to influence the hypothalamic-pituitary-adrenal axis, here we test whether PFC and amygdala responses during emotion regulation predict the diurnal pattern of salivary cortisol secretion. We also test whether PFC and amygdala regions are engaged during emotion regulation in older (62- to 64-year-old) rather than younger individuals. We measured brain activity using functional magnetic resonance imaging as participants regulated (increased or decreased) their affective responses or attended to negative picture stimuli. We also collected saliva samples for 1 week at home for cortisol assay. Consistent with previous work in younger samples, increasing nega…

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Attention-deficit hyperactivity disorder symptoms add risk to circadian rhythm sleep problems in depression and anxiety.

Background: Comorbid ADHD symptoms may partly account for circadian rhythm disturbances in depression and anxiety disorders. Methods: Self-reported sleep characteristics of 2090 participants in the Netherlands Study of Depression and Anxiety were assessed using the Munich Chronotype Questionnaire. We defined 3 groups: healthy controls (HC), persons with lifetime depression and/or anxiety disorders (LDA), and those with both LDA and high ADHD symptoms (LDA+ADHD), using the Conner's Adult ADHD Rating Scale. Results: Sleep characteristics were least favorable in the LDA+ADHD group. Important group differences between LDA+ADHD, LDA and HC were found for extremely late chronotype (12% vs. 5% vs. 3%; p<.001), sleep duration <6h (15% vs. 5% vs. 4%; p<.001), and for an indication of the Delayed Sleep Phase Syndrome (DSPS; 16% vs. 8% vs. 5%; p<.001). After adjustment for covariates, including dep…

matched on Circadian Rhythm (mesh), Sleep Disorders, Circadian Rhythm (mesh), chronotype (text), circadian (text)

Shift work disorder and the prevalence of help seeking behaviors for sleep concerns in Australia: A descriptive study.

Shift work disorder (SWD) is a circadian rhythm sleep-wake disorder, defined by symptoms of insomnia and excessive levels of sleepiness resulting from work that occurs during non-standard hours. Sleep problems are common in shift workers, yet our understanding of help seeking behaviours for sleep in shift workers is limited. The primary aim of this study was to examine the help seeking behaviours of Australian workers who meet criteria for SWD. Of the 448 (46% of sample, n = 964 total) Australian workers reporting non-standard work hours, 10.5% (n = 41) met the criteria for probable shift work disorder (pSWD). Non-standard workers with pSWD did not seek help for sleep problems at higher rates than workers without SWD. Of the small proportion of workers with pSWD who sought help, general practitioners were the most common healthcare professionals for sleep problems. Self-management was co…

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Sleep inertia, sleep homeostatic and circadian influences on higher-order cognitive functions.

Sleep inertia, sleep homeostatic and circadian processes modulate cognition, including reaction time, memory, mood and alertness. How these processes influence higher-order cognitive functions is not well known. Six participants completed a 73-day-long study that included two 14-day-long 28-h forced desynchrony protocols to examine separate and interacting influences of sleep inertia, sleep homeostasis and circadian phase on higher-order cognitive functions of inhibitory control and selective visual attention. Cognitive performance for most measures was impaired immediately after scheduled awakening and improved during the first ~2-4 h of wakefulness (decreasing sleep inertia); worsened thereafter until scheduled bedtime (increasing sleep homeostasis); and was worst at ~60° and best at ~240° (circadian modulation, with worst and best phases corresponding to ~09:00 and ~21:00 hours, respe…

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How the circadian rhythm affects sleep, wakefulness, and overall health: background for understanding shift work disorder.

It is estimated that 15 to 25% of the U.S. labor force works night, evening, or rotating shifts. These non-traditional schedules can affect the circadian rhythm, a self-sustained rhythm of biological processes that plays an important role in modulating sleep/wake function, resulting in circadian rhythm sleep disorder, shift work type, usually referred to as shift work disorder. The disorder consists of a constant or recurrent pattern of sleep interruption that results in insomnia when sleep is needed and excessive sleepiness during waking hours. Clinicians need more information about the role of the circadian rhythm in human functioning as well as the pathophysiology, prevalence, and consequences of shift work disorder, so that they can recognize and diagnose this problem in clinical practice.

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Validation of a questionnaire to screen for shift work disorder.

Study objective: At least 15% of the full-time work force is shift workers. Working during the overnight hours, early morning start times, and variable or rotating schedules present a challenge to the circadian system, and these shifts are associated with adverse health and safety consequences. Shift work disorder (SWD), a primary (circadian rhythm) sleep disorder indicated by excessive daytime sleepiness and/or insomnia associated with a shiftwork schedule, is under-recognized by primary care physicians. We sought to develop and validate a questionnaire to screen for high risk of SWD in a shift working population. Design: Shift workers completed a 26-item questionnaire and were evaluated by a sleep specialist (physician) who diagnosed them as either positive or negative for SWD. The physician assessment of SWD was guided by a flow chart that operationalized the ICSD-2 criteria for SWD. …

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Blue light and melatonin: A critical review of scientific evidence and biohacker myths in ophthalmology.

Blue light is a physiological component of visible light, essential for daytime vision and circadian synchronization. There is no evidence supporting the routine use of blue-blocking glasses for preventive or therapeutic purposes. The most effective strategies are based on light hygiene, reduction of nocturnal exposure, and patient education. Strengthening scientific communication is necessary to counter misinformation and maintain an evidence-based ophthalmological discourse. Blue light has been associated with potential effects on visual function, sleep, and circadian physiology, although clinical evidence remains heterogeneous. In recent years, dissemination of claims unsupported by clinical evidence regarding spectral filters for preventive purposes has increased. The aim of this review was to critically analyze the available scientific evidence on the visual, circadian, and systemic…

matched on Circadian Rhythm (keyword), Melatonin (keyword), circadian (text), light exposure (text)

Sleep restriction therapy for insomnia is associated with reduced objective total sleep time, increased daytime somnolence, and objectively impaired vigilance: implications for the clinical management of insomnia disorder.

Study objectives: To investigate whether sleep restriction therapy (SRT) is associated with reduced objective total sleep time (TST), increased daytime somnolence, and impaired vigilance. Design: Within-subject, noncontrolled treatment investigation. Setting: Sleep research laboratory. Participants: Sixteen patients [10 female, mean age = 47.1 (10.8) y] with well-defined psychophysiological insomnia (PI), reporting TST ≤ 6 h. Interventions: Patients were treated with single-component SRT over a 4-w protocol, sleeping in the laboratory for 2 nights prior to treatment initiation and for 3 nights (SRT night 1, 8, 22) during the acute interventional phase. The psychomotor vigilance task (PVT) was completed at seven defined time points [day 0 (baseline), day 1,7,8,21,22 (acute treatment) and day 84 (3 mo)]. The Epworth Sleepiness Scale (ESS) was completed at baseline, w 1-4, and 3 mo. Measure…

matched on Sleep Stages (mesh), Wakefulness (mesh)

Melatonin attenuates chronic sleep deprivation-induced cognitive deficits and HDAC3-Bmal1/clock interruption.

Background and aims: Sleep is predicted as a key modulator of cognition, but the underlying mechanisms are poorly understood. In this study, we investigated the effects of melatonin on chronic rapid eye movement sleep deprivation (CRSD)-induced cognitive impairment and circadian dysfunction in rat models. Methods: Thirty-six Sprague-Dawley male rats were divided into three groups: CRSD with saline treatment, CRSD with chronic melatonin injection (20 mg/kg/day), and non-sleep-deprived control. The cognitive behavioral tests as well as the expression of clocks and HDAC3 were evaluated in all groups. Results: CRSD significantly reduced recognition index in novel object location, increased escape latency and distance traveling in Morris water maze while melatonin treatment attenuated CRSD-induced hippocampal-dependent spatial learning and memory deficits. Furthermore, the mRNAs of brain and …

matched on Circadian Rhythm (mesh), Melatonin (mesh), Circadian Rhythm (keyword), circadian (text)

Sleep quality, morningness-eveningness preference, mood profile, and levels of serum melatonin in migraine patients: a case-control study.

The melatonin as the pineal gland's secretory product is implicated in the pathophysiology of migraine. Melatonin has critical functions in human physiology, and research underscores the importance of melatonin in circadian rhythm, sleep, and mood regulation. Clinical observations have indicated that migraine attacks have a seasonal, menstrual, and circadian timing, suggesting that chronobiological mechanisms and their alterations may causally involve in the etiology of the disease. However, the topic has received relatively little attention in the migraine literature. Associations between melatonin, circadian preference, sleep, and mood states were investigated in the current study. Fifty-five patients (47 females and 8 males) were compared to 57 gender and age-matched control subjects (40 females and 17 males). A socio-demographical questionnaire, the Beck Depression Inventory, Beck An…

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Bright light therapy for depression: a review of its effects on chronobiology and the autonomic nervous system.

Bright light therapy (BLT) is considered among the first-line treatments for seasonal affective disorder (SAD), yet a growing body of literature supports its use in other neuropsychiatric conditions including non-seasonal depression. Despite evidence of its antidepressant efficacy, clinical use of BLT remains highly variable internationally. In this article, we explore the autonomic effects of BLT and suggest that such effects may play a role in its antidepressant and chronotherapeutic properties. After providing a brief introduction on the clinical application of BLT, we review the chronobiological effects of BLT on depression and on the autonomic nervous system in depressed and non-depressed individuals with an emphasis on non-seasonal depression. Such a theory of autonomic modulation via BLT could serve to integrate aspects of recent work centered on alleviating allostatic load, the p…

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Effects of nature-adapted lighting solutions ("Virtual Sky") on subjective and objective correlates of sleepiness, well-being, visual and cognitive performance at the workplace.

Exposure to natural daylight benefits human well-being, alertness, circadian rhythms and sleep. Many workplaces have limited or no access to daylight. Thus, we implemented a light-panel ("Virtual Sky"), which reproduced nature-adapted light scenarios. In a laboratory office environment, three lighting scenarios were presented during the day: two lighting conditions with nature-adapted spectral light distributions, one with static and one with dynamic clouds, and a standard office lighting condition. We compared the impact of the three lighting scenarios on subjective and objective measures of alertness, cognitive performance, wellbeing, visual comfort, contrast sensitivity, and cortisol levels in 18 healthy young male volunteers in a within-participant cross-over study design. We found no evidence that an 8-h lighting scenario with static or dynamic clouds during the waking day (9am-5pm)…

matched on Circadian Rhythm (mesh), Melatonin (mesh), Light (mesh), circadian (text)

Estimating the dim light melatonin onset of adolescents within a 6-h sampling window: the impact of sampling rate and threshold method.

Objective/background: Circadian rhythm sleep-wake disorders (CRSWDs) often manifest during the adolescent years. Measurement of circadian phase such as the dim light melatonin onset (DLMO) improves diagnosis and treatment of these disorders, but financial and time costs limit the use of DLMO phase assessments in clinic. The current analysis aims to inform a cost-effective and efficient protocol to measure the DLMO in older adolescents by reducing the number of samples and total sampling duration. Patients/methods: A total of 66 healthy adolescents (26 males) aged 14.8-17.8 years participated in a study; they were required to sleep on a fixed baseline schedule for a week before which they visited the laboratory for saliva collection in dim light (<20 lux). Two partial 6-h salivary melatonin profiles were derived for each participant. Both profiles began 5 h before bedtime and ended 1 h af…

matched on Sleep Disorders, Circadian Rhythm (mesh), Melatonin (mesh), Light (mesh), circadian (text)

Plasticity of the intrinsic period of the human circadian timing system.

Human expeditions to Mars will require adaptation to the 24.65-h Martian solar day-night cycle (sol), which is outside the range of entrainment of the human circadian pacemaker under lighting intensities to which astronauts are typically exposed. Failure to entrain the circadian time-keeping system to the desired rest-activity cycle disturbs sleep and impairs cognitive function. Furthermore, differences between the intrinsic circadian period and Earth's 24-h light-dark cycle underlie human circadian rhythm sleep disorders, such as advanced sleep phase disorder and non-24-hour sleep-wake disorders. Therefore, first, we tested whether exposure to a model-based lighting regimen would entrain the human circadian pacemaker at a normal phase angle to the 24.65-h Martian sol and to the 23.5-h day length often required of astronauts during short duration space exploration. Second, we tested here…

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Working night shifts affects surgeons' biological rhythm.

Background: Chronic sleep deprivation combined with work during the night is known to affect performance and compromise residents' own safety. The aim of this study was to examine markers of circadian rhythm and the sleep-wake cycle in surgeons working night shifts. Methods: Surgeons were monitored prospectively for 4 days: pre call, on call, post call day 1 (PC1), and post call day 2 (PC2). The urinary metabolite of melatonin and cortisol in saliva were measured to assess the circadian rhythm. Sleep and activity were measured by actigraphy. Subjective measures were assessed by the Karolinska Sleepiness Scale and Visual Analog Scale of fatigue, general well-being, and sleep quality. Results: For both metabolite of melatonin and cortisol, a significant difference (P < .05) was found in the measurement period between on call and pre call values. There was increased sleep time during the da…

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