Motivation, reward and anhedonia

يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓاْ إِذَا تَدَايَنتُم بِدَيۡنٍ إِلَىٰٓ أَجَلࣲ مُّسَمࣰّ ى فَٱكۡتُبُوهُۚ وَلۡيَكۡتُب بَّيۡنَكُمۡ كَاتِبُۢ بِٱلۡعَدۡلِۚ وَلَا يَأۡبَ كَاتِبٌ أَن يَكۡتُبَ كَمَا عَلَّمَهُ ٱللَّهُۚ فَلۡيَكۡتُبۡ وَلۡيُمۡلِلِ ٱلَّذِي عَلَيۡهِ ٱلۡحَقُّ وَلۡيَتَّقِ ٱللَّهَ رَبَّهُۥ وَلَا يَبۡخَسۡ مِنۡهُ شَيۡـࣰٔ اۚ فَإِن كَانَ ٱلَّذِي عَلَيۡهِ ٱلۡحَقُّ سَفِيهًا أَوۡ ضَعِيفًا أَوۡ لَا يَسۡتَطِيعُ أَن يُمِلَّ هُوَ فَلۡيُمۡلِلۡ وَلِيُّهُۥ بِٱلۡعَدۡلِۚ وَٱسۡتَشۡهِدُواْ شَهِيدَيۡنِ مِن رِّجَالِكُمۡۖ فَإِن لَّمۡ يَكُونَا رَجُلَيۡنِ فَرَجُلࣱ وَٱمۡرَأَتَانِ مِمَّن تَرۡضَوۡنَ مِنَ ٱلشُّهَدَآءِ أَن تَضِلَّ إِحۡدَىٰهُمَا فَتُذَكِّرَ إِحۡدَىٰهُمَا ٱلۡأُخۡرَىٰۚ وَلَا يَأۡبَ ٱلشُّهَدَآءُ إِذَا مَا دُعُواْۚ وَلَا تَسۡـَٔمُوٓاْ أَن تَكۡتُبُوهُ صَغِيرًا أَوۡ كَبِيرًا إِلَىٰٓ أَجَلِهِۦۚ ذَٰلِكُمۡ أَقۡسَطُ عِندَ ٱللَّهِ وَأَقۡوَمُ لِلشَّهَٰدَةِ وَأَدۡنَىٰٓ أَلَّا تَرۡتَابُوٓاْ إِلَّآ أَن تَكُونَ تِجَٰرَةً حَاضِرَةࣰ تُدِيرُونَهَا بَيۡنَكُمۡ فَلَيۡسَ عَلَيۡكُمۡ جُنَاحٌ أَلَّا تَكۡتُبُوهَاۗ وَأَشۡهِدُوٓاْ إِذَا تَبَايَعۡتُمۡۚ وَلَا يُضَآرَّ كَاتِبࣱ وَلَا شَهِيدࣱۚ وَإِن تَفۡعَلُواْ فَإِنَّهُۥ فُسُوقُۢ بِكُمۡۗ وَٱتَّقُواْ ٱللَّهَۖ وَيُعَلِّمُكُمُ ٱللَّهُۗ وَٱللَّهُ بِكُلِّ شَيۡءٍ عَلِيمࣱ‏

You who believe, when you contract a debt for a stated term, put it down in writing: have a scribe write it down justly between you. No scribe should refuse to write: let him write as God has taught him, let the debtor dictate, and let him fear God, his Lord, and not diminish [the debt] at all. If the debtor is feeble-minded, weak, or unable to dictate, then let his guardian dictate justly. Call in two men as witnesses. If two men are not there, then call one man and two women out of those you approve as witnesses, so that if one of the two women should forget the other can remind her. Let the witnesses not refuse when they are summoned. Do not disdain to write the debt down, be it small or large, along with the time it falls due: this way is more equitable in God’s eyes, more reliable as testimony, and more likely to prevent doubts arising between you. But if the merchandise is there and you hand it over, there is no blame on you if you do not write it down. Have witnesses present whenever you trade with one another, and let no harm be done to either scribe or witness, for if you did cause them harm, it would be a crime on your part. Be mindful of God, and He will teach you: He has full knowledge of everything

O you who believe when you contract when you are dealing with a debt such as in prepayment for future delivery of goods or a loan one upon another for a stated a known term write it down as confirmation and security against any dispute; and let a writer write it the contract of debt down between you justly accurately not increasing or decreasing the amount or the terms; and let not any writer refuse to write it down if he is requested for such a task as God has taught him the kāf of ka-mā ‘as’ is semantically connected to the verb ya’ba ‘refuse’ that is just as He has given him the advantage of knowing how to write he should not be niggardly in this respect; so let him write repeated for emphasis and let the debtor dictate to the one writing the contract for he is the one being witnessed and must be fully aware of his obligations; and let him fear God his Lord when dictating and not dimi

O you who believe! When you contract a debt for a fixed period, write it down. Let a scribe write it down in justice between you. Let not the scribe refuse to write, as Allah has taught him, so let him write. Let him (the debtor) who incurs the liability dictate, and he must have Taqwa of Allah, his Lord, and diminish not anything of what he owes. But if the debtor is of poor understanding, or weak, or is unable to dictate for himself, then let his guardian dictate in justice. And get two witnesses out of your own men. And if there are not two men (available), then a man and two women, such as you agree for witnesses, so that if one of them (two women) errs, the other can remind her. And the witnesses should not refuse when they are called (for evidence). You should not become weary to write it (your contract), whether it be small or big, for its fixed term, that is more just with Allah;

حَدَّثَنَا هَدَّابُ بْنُ خَالِدٍ، حَدَّثَنَا حَمَّادُ بْنُ سَلَمَةَ، ح وَحَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا مُعَاذُ بْنُ مُعَاذٍ الْعَنْبَرِيُّ، ح وَحَدَّثَنِي مُحَمَّدُ بْنُ عَبْدِ الأَعْلَى، حَدَّثَنَا الْمُعْتَمِرُ، ح وَحَدَّثَنَا إِسْحَاقُ، بْنُ إِبْرَاهِيمَ أَخْبَرَنَا جَرِيرٌ، كُلُّهُمْ عَنْ سُلَيْمَانَ التَّيْمِيِّ، ح وَحَدَّثَنَا أَبُو كَامِلٍ، فُضَيْلُ بْنُ حُسَيْنٍ - وَاللَّفْظُ لَهُ - حَدَّثَنَا يَزِيدُ بْنُ زُرَيْعٍ، حَدَّثَنَا التَّيْمِيُّ، عَنْ أَبِي عُثْمَانَ، عَنْ أُسَامَةَ بْنِ زَيْدٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ قُمْتُ عَلَى بَابِ الْجَنَّةِ فَإِذَا عَامَّةُ مَنْ دَخَلَهَا الْمَسَاكِينُ وَإِذَا أَصْحَابُ الْجَدِّ مَحْبُوسُونَ إِلاَّ أَصْحَابَ النَّارِ فَقَدْ أُمِرَ بِهِمْ إِلَى النَّارِ وَقُمْتُ عَلَى بَابِ النَّارِ فَإِذَا عَامَّةُ مَنْ دَخَلَهَا النِّسَاءُ ‏"‏ ‏.‏

Usama b. Zaid reported that Allah's Messenger (way peace be upon him) said:I stood at the door of Paradise and I found that the overwhelming majority of those who entered therein was that of poor persons and the wealthy persons were detained to get into that. The denizens of Hell were commanded to get into Hell, and I stood upon the door of Fire and the majority amongst them who entered there was that of women

حَدَّثَنَا أَبُو كُرَيْبٍ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ سَعِيدِ بْنِ أَبِي عَرُوبَةَ، سَمِعَ أَبَا رَجَاءٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم فَذَكَرَ مِثْلَهُ ‏.‏

This hadith is narrated likewise through another chain of transmitters

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ بْنِ قَعْنَبٍ، حَدَّثَنَا سُلَيْمَانُ، - يَعْنِي ابْنَ بِلاَلٍ - عَنْ جَعْفَرٍ، عَنْ أَبِيهِ، عَنْ جَابِرِ بْنِ عَبْدِ اللَّهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم مَرَّ بِالسُّوقِ دَاخِلاً مِنْ بَعْضِ الْعَالِيَةِ وَالنَّاسُ كَنَفَتَهُ فَمَرَّ بِجَدْىٍ أَسَكَّ مَيِّتٍ فَتَنَاوَلَهُ فَأَخَذَ بِأُذُنِهِ ثُمَّ قَالَ ‏"‏ أَيُّكُمْ يُحِبُّ أَنَّ هَذَا لَهُ بِدِرْهَمٍ ‏"‏ ‏.‏ فَقَالُوا مَا نُحِبُّ أَنَّهُ لَنَا بِشَىْءٍ وَمَا نَصْنَعُ بِهِ قَالَ ‏"‏ أَتُحِبُّونَ أَنَّهُ لَكُمْ ‏"‏ ‏.‏ قَالُوا وَاللَّهِ لَوْ كَانَ حَيًّا كَانَ عَيْبًا فِيهِ لأَنَّهُ أَسَكُّ فَكَيْفَ وَهُوَ مَيِّتٌ فَقَالَ ‏"‏ فَوَاللَّهِ لَلدُّنْيَا أَهْوَنُ عَلَى اللَّهِ مِنْ هَذَا عَلَيْكُمْ ‏"‏ ‏.‏

Jabir b. Abdullah reported that Allah's Apostle (ﷺ) happened to walk through the bazar coming from the side of 'Aliya and the people were on both his sides. There he found a dead lamb with very short ears. He took hold of his ear and said:Who amongst you would like to have this for a dirham? They said: We do not like to have it even for less than that as it is of no use to us. He said: Do you wish to have it (free of any cost)? They said: By Allah, even if it were alive (we would not have liked to possess that), for there is defect in it as its ear is very short; now it is dead also. Thereupon Allah's Messenger (ﷺ) said: By Allah, this world is more insignificant in the eye of Allah than it (this dead lamb) is in your eye

حَدَّثَنِي مُحَمَّدُ بْنُ الْمُثَنَّى الْعَنَزِيُّ، وَإِبْرَاهِيمُ بْنُ مُحَمَّدِ بْنِ عَرْعَرَةَ السَّامِيُّ، قَالاَ حَدَّثَنَا عَبْدُ الْوَهَّابِ، - يَعْنِيَانِ الثَّقَفِيَّ - عَنْ جَعْفَرٍ، عَنْ أَبِيهِ، عَنْ جَابِرٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم ‏.‏ بِمِثْلِهِ غَيْرَ أَنَّ فِي حَدِيثِ الثَّقَفِيِّ فَلَوْ كَانَ حَيًّا كَانَ هَذَا السَّكَكُ بِهِ عَيْبًا ‏.‏

Jabir reported Allah's Apostle (ﷺ) narrating a hadith like this with a slight variation of wording

حَدَّثَنَا الْمَكِّيُّ بْنُ إِبْرَاهِيمَ، أَخْبَرَنَا عَبْدُ اللَّهِ بْنُ سَعِيدٍ ـ هُوَ ابْنُ أَبِي هِنْدٍ ـ عَنْ أَبِيهِ، عَنِ ابْنِ عَبَّاسٍ ـ رضى الله عنهما ـ قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم ‏ "‏ نِعْمَتَانِ مَغْبُونٌ فِيهِمَا كَثِيرٌ مِنَ النَّاسِ، الصِّحَّةُ وَالْفَرَاغُ ‏"‏‏.‏ قَالَ عَبَّاسٌ الْعَنْبَرِيُّ حَدَّثَنَا صَفْوَانُ بْنُ عِيسَى، عَنْ عَبْدِ اللَّهِ بْنِ سَعِيدِ بْنِ أَبِي هِنْدٍ، عَنْ أَبِيهِ، سَمِعْتُ ابْنَ عَبَّاسٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم مِثْلَهُ‏.‏

Narrated Ibn `Abbas:The Prophet (ﷺ) said: "There are two blessings that many people are deceived into losing: health and free time

حَدَّثَنِي أَحْمَدُ بْنُ الْمِقْدَامِ، حَدَّثَنَا الْفُضَيْلُ بْنُ سُلَيْمَانَ، حَدَّثَنَا أَبُو حَازِمٍ، حَدَّثَنَا سَهْلُ بْنُ سَعْدٍ السَّاعِدِيُّ، كُنَّا مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم فِي الْخَنْدَقِ وَهْوَ يَحْفِرُ وَنَحْنُ نَنْقُلُ التُّرَابَ وَيَمُرُّ بِنَا فَقَالَ ‏ "‏ اللَّهُمَّ لاَ عَيْشَ إِلاَّ عَيْشُ الآخِرَهْ، فَاغْفِرْ لِلأَنْصَارِ وَالْمُهَاجِرَهْ ‏"‏‏.‏ تَابَعَهُ سَهْلُ بْنُ سَعْدٍ عَنِ النَّبِيِّ صلى الله عليه وسلم مِثْلَهُ‏.‏

Narrated Sahl bin Sa`d As-Sa`idi:We were in the company of Allah's Messenger (ﷺ) in (the battle of) Al-Khandaq, and he was digging the trench while we were carrying the earth away. He looked at us and said, "O Allah! There is no life worth living except the life of the Hereafter, so (please) forgive the Ansar and the Emigrants

ومن آدابه: أن لا يمتلئ من الطعام فى الليل، بل يأكل بمقدار، فانه ما ملأ ابن آدم وعاء شرا من بطن. ومتى شبع أول الليل لم ينتفع بنفسه فى باقيه، وكذلك إذا شبع وقت السحر لم ينتفع بنفسه إلى قريب من الظهر، لأن كثرة الأكل تورث الكسل والفتور، ثم يفوت المقصود من الصيام بكثرة الأكل، لأن المراد منه أن يذوق طعم الجوع، ويكون تاركا للمشتهى.

بين القبض والبسط أي ينقطع إلى صحبة الحال وهو الوارد الذي يرد على القلب من تأثيره بالمعاملة السالب لوصف الكسل والفتور الجالب له إلى مرافقة الرفيق الأعلى الذين أنعم الله عليهم فينتقل من مقام العلم إلى مقام الكشف ومن مقام رسوم الأعمال إلى مقام حقائقها وأذواقها ومواجيدها وأحوالها فيترقى من الإسلام إلى الإيمان ومن الإيمان إلى الإحسان

فحقيقة التعظيم للامر والنهي ان لا يعارضا بترخص جاف ولا يعرضا لتشديد غال فان المقصود هو الصراط المستقيم الموصل إلى الله عز وجل بسالكه وما امر الله عز وجل بأمر الا وللشيطان فيه نزغتان اما تقصير وتفريط واما افراط وغلو فلا يبالي بما ظفر من العبد من الخطيئتين فانه ياتي إلى قلب العبد فيستامه فان وجد فيه فتورا وتوانيا وترخيصا اخذه من هذه الخطة فثبطه واقعده وضربه بالكسل والتواني والفتور وفتح له باب التاويلات والرجاء وغير ذلك حتى ربما ترك العبد المامور جملة

العزيمة فيصدقه في عزمه وفي فعله قال تعالى فإذا عزم الأمر فلو صدقوا الله لكان خيرا لهم فسعادته في صدق العزيمة وصدق الفعل فصدق العزيمة جمعها وجزمها وعدم التردد فيها بل تكون عزيمة لا يشوبها تردد ولا تلوم فإذا صدقت عزيمته بقى عليه صدق الفعل وهو استفراغ الوسع وبذل الجهد فيه وأن لا يتخلف عنه بشيء من ظاهره وباطنه فعزيمة القصد تمنعه من ضعف الإرادة والهمة وصدق الفعل يمنعه من الكسل والفتور ومن صدق الله في جميع أموره صنع الله له فوق ما يصنع لغيره وهذا الصدق معنى يلتئم من صحة الإخلاص وصدق التوكل فأصدق الناس من صح إخلاصه وتوكله

فالإيمان بالصفات ومعرفتها وإثبات حقائقها وتعلق القلب بها وشهوده لها هو مبدأ الطريق ووسطه وغايته وهو روح السالكين وحاديهم إلى الوصول ومحرك عزماتهم إذا فتروا ومثير هممهم إذا قصروا فإن سيرهم إنما هو على الشواهد فمن كان لا شاهد له فلا سير له ولا طلب ولا سلوك له وأعظم الشواهد صفات محبوبهم ونهاية مطلوبهم وذلك هو العلم الذي رفع لهم في السير فشمروا إليه كما قالت عائشة رضي الله عنها من رأى رسول الله فقد رآه غاديا رائحا لم يضع لبنة على لبنة ولكن رفع له علم فشمر إليه ولا يزال العبد في التواني والفتور والكسل حتى يرفع الله عز وجل له بفضله ومنه علما يشاهده بقلبه فيشمر إليه ويعمل عليه

قال الله تعالى : ففروا إلى الله الذاريات : 50 ] وحقيقة الفرار : الهرب من شيء إلى شيء وهو نوعان : فرار السعداء وفرار الأشقياء ففرار السعداء : الفرار إلى الله عز وجل وفرار الأشقياء : الفرار منه لا إليه وأما الفرار منه إليه : ففرار أوليائه قال ابن عباس في قوله تعالى : ففروا إلى الله الذاريات : 50 ] : فروا منه إليه واعملوا بطاعته وقال سهل بن عبدالله : فروا مما سوى الله إلى الله وقال آخرون : اهربوا من عذاب الله إلى ثوابه بالإيمان والطاعة وقال صاحب المنازل : هو الهرب مما لم يكن إلى من لم يزل وهو على ثلاث درجات : فرار العامة من الجهل إلى العلم عقدا وسعيا ومن الكسل إلى التشمير جدا وعزما ومن الضيق إلى السعة ثقة ورجاء يريد بما لم يكن الخلق وبما لم يزل الحق وقوله : فرار العامة : من الجهل إلى العلم عقدا وسعيا الجهل نوعان : عدم العلم بالحق النافع وعدم العمل بموجبه ومقتضاه فكلاهما جهل لغة وعرفا وشرعا وحقيقة قال موسى : أعوذ بالله أن أكون من الجاهلين البقره : 67 ] لما قال له قومه : أتتخذنا هزوا البقره :

Anhedonia as a central factor in depression: Neural mechanisms revealed from preclinical to clinical evidence.: Anhedonia is one of the core symptoms of major depressive disorder (MDD), which is often inadequately treated by traditional antidepressants. The modern framework of anhedonia extends the definition from impaired consummatory pleasure or interest in rewards to a broad spectrum of deficits that impact functions such as reward anticipation, approach motivation, effort expenditure, reward valuation, expectation, and reward-cue association learning. Substantial preclinical and clinical research has

How to improve reward sensitivity - Predictors of long-term effects of a randomized controlled online intervention trial.: Background: Reward sensitivity is a central maintaining factor of depression. Current treatments fail at sufficiently and reliably modifying reward processing. Therefore, we employed interventions targeting reward sensitivity and evaluated the long-term efficacy of different online interventions, additionally exploring predictors of changes in reward sensitivity. Methods: This four-arm randomized controlled trial (RCT) tested the long-term stability of treatment effects during a four-month follo

Effectiveness of behavioral activation and mindfulness in increasing reward sensitivity and reducing depressive symptoms - A randomized controlled trial.: Reward insensitivity is a potential key mechanism regarding the maintenance of depression. However, there is a lack of research examining and comparing the effectiveness of different psychological interventions in modifying reward insensitivity. This four-arm randomized controlled trial (RCT) investigated a two-week online intervention. After screening for eligibility, a total of 336 participants were randomized, and 224 participated per-protocol. Participants were assigned to either a) behavior

'We pledge to improve the health of our entire community': Improving health worker motivation and performance in Bihar, India through teamwork, recognition, and non-financial incentives.: Background: Motivation is critical to health worker performance and work quality. In Bihar, India, frontline health workers provide essential health services for the state's poorest citizens. Yet, there is a shortfall of motivated and skilled providers and a lack of coordination between two cadres of frontline health workers and their supervisors. CARE India developed an approach aimed at improving health workers' performance by shifting work culture and strengthening teamwork and motivation. Th

A systematic review and meta-analysis of the effort-reward imbalance model of workplace stress with indicators of immune function.: Objective: Despite considerable research into associations between the effort reward imbalance (ERI) model and various health outcomes over the past 20years, the underlying mechanisms responsible for the association remain unclear. Recently, ERI investigations have examined associations with immune sub-systems (e.g., leukocytes, cytokines and immunoglobulins). Synthesis of the amalgamated research evidence will aid clarity to this field of enquiry. We conducted a meta-analysis and reviewed the a

The utility of monetary contingency contracts for weight loss: a systematic review and meta-analysis.: Financial incentives to improve health have received increasing attention, but are subject to ethical concerns. Monetary Contingency Contracts (MCCs), which require individuals to deposit money that is refunded contingent on reaching a goal, are a potential alternative strategy. This review evaluates systematically the evidence for weight loss-related MCCs. Randomised controlled trials testing the effect of weight loss-related MCCs were identified in online databases. Random-effects meta-analyse

Reward and choice encoding in terminals of midbrain dopamine neurons depends on striatal target.

Dopaminergic (DA) neurons in the midbrain provide rich topographic innervation of the striatum and are central to learning and to generating actions. Despite the importance of this DA innervation, it remains unclear whether and how DA neurons are specialized on the basis of the location of their striatal target. Thus, we sought to compare the function of subpopulations of DA neurons that target distinct striatal subregions in the context of an instrumental reversal learning task. We identified key differences in the encoding of reward and choice in dopamine terminals in dorsal versus ventral striatum: DA terminals in ventral striatum responded more strongly to reward consumption and reward-predicting cues, whereas DA terminals in dorsomedial striatum responded more strongly to contralateral choices. In both cases the terminals encoded a reward prediction error. Our results suggest that t…

matched on Reward (mesh)

Exposure to an inflammatory challenge enhances neural sensitivity to negative and positive social feedback.

Inflammation, part of the body's innate immune response, can lead to "sickness behaviors," as well as alterations in social and affective experiences. Elevated levels of pro-inflammatory cytokines have been associated with increased neural sensitivity to social rejection and social threat, but also decreased neural sensitivity to rewards. However, recent evidence suggests that inflammation may actually enhance sensitivity to certain social rewards, such as those that signal support and care. Despite a growing interest in how inflammation influences neural reactivity to positive and negative social experiences, no known studies have investigated these processes in the same participants, using a similar task. To examine this issue, 107 participants were randomly assigned to receive either placebo or low-dose endotoxin, which safely triggers an inflammatory response. When levels of pro-infl…

matched on Reward (mesh)

Midbrain dopamine neurons compute inferred and cached value prediction errors in a common framework.

Midbrain dopamine neurons have been proposed to signal reward prediction errors as defined in temporal difference (TD) learning algorithms. While these models have been extremely powerful in interpreting dopamine activity, they typically do not use value derived through inference in computing errors. This is important because much real world behavior - and thus many opportunities for error-driven learning - is based on such predictions. Here, we show that error-signaling rat dopamine neurons respond to the inferred, model-based value of cues that have not been paired with reward and do so in the same framework as they track the putative cached value of cues previously paired with reward. This suggests that dopamine neurons access a wider variety of information than contemplated by standard TD models and that, while their firing conforms to predictions of TD models in some cases, they may…

matched on Reward (mesh)

Problematic Internet Users' Discounting Behaviors Reflect an Inability to Delay Gratification, Not Risk Taking.

The relationship between impulse control disorder (ICD) behaviors and problematic Internet use (PIU) has been established in the literature. Our aim was to further investigate whether the ICDs of individuals suffering from PIU primarily involve an inability to delay gratification or a tendency to take risks. Using delay and probability discounting tasks, we compared the subjective value of discounting between PIU individuals and controls in conditions of gaining or losing different monetary amounts. The results of the present study revealed a significant positive relationship between PIU and impulsivity scores. PIU individuals discounted delayed amounts more steeply than controls, regardless of the reward sign and monetary amount. Conversely, there were no significant group differences in the probability discounting task. These findings suggest that PIU individuals may be more impulsive …

matched on Reward (mesh)

Rapid signalling in distinct dopaminergic axons during locomotion and reward.

Dopaminergic projection axons from the midbrain to the striatum are crucial for motor control, as their degeneration in Parkinson disease results in profound movement deficits. Paradoxically, most recording methods report rapid phasic dopamine signalling (~100-ms bursts) in response to unpredicted rewards, with little evidence for movement-related signalling. The leading model posits that phasic signalling in striatum-targeting dopamine neurons drives reward-based learning, whereas slow variations in firing (tens of seconds to minutes) in these same neurons bias animals towards or away from movement. However, current methods have provided little evidence to support or refute this model. Here, using new optical recording methods, we report the discovery of rapid phasic signalling in striatum-targeting dopaminergic axons that is associated with, and capable of triggering, locomotion in mic…

matched on Reward (mesh)

The Role of Dopamine in Value-Based Attentional Orienting.

Reward learning gives rise to strong attentional biases. Stimuli previously associated with reward automatically capture visual attention regardless of intention. Dopamine signaling within the ventral striatum plays an important role in reward learning, representing the expected reward initiated by a cue. How dopamine and the striatum may be involved in maintaining behaviors that have been shaped by reward learning, even after reward expectancies have changed, is less well understood. Nonspecific measures of brain activity have implicated the striatum in value-based attention. However, the neurochemical mechanisms underlying the attentional priority of learned reward cues remain unexplored. Here, we investigated the contribution of dopamine to value-based attention using positron emission tomography (PET) with [(11)C]raclopride. We show that, in the explicit absence of reward, the magnit…

matched on Reward (mesh)

Blunted Neural Response to Rewards as a Prospective Predictor of the Development of Depression in Adolescent Girls.

Objective: A blunted neural response to rewards has recently emerged as a potential mechanistic biomarker of adolescent depression. The reward positivity, an event-related potential elicited by feedback indicating monetary gain relative to loss, has been associated with risk for depression. The authors examined whether the reward positivity prospectively predicted the development of depression 18 months later in a large community sample of adolescent girls. Method: The sample included 444 girls 13.5-15.5 years old with no lifetime history of a depressive disorder, along with a biological parent for each girl. At baseline, the adolescents' reward positivity was measured using a monetary guessing task, their current depressive symptoms were assessed using a self-report questionnaire, and the adolescents' and parents' lifetime psychiatric histories were evaluated with diagnostic interviews.…

matched on Reward (mesh)

Dynamic mesolimbic dopamine signaling during action sequence learning and expectation violation.

Prolonged mesolimbic dopamine concentration changes have been detected during spatial navigation, but little is known about the conditions that engender this signaling profile or how it develops with learning. To address this, we monitored dopamine concentration changes in the nucleus accumbens core of rats throughout acquisition and performance of an instrumental action sequence task. Prolonged dopamine concentration changes were detected that ramped up as rats executed each action sequence and declined after earned reward collection. With learning, dopamine concentration began to rise increasingly earlier in the execution of the sequence and ultimately backpropagated away from stereotyped sequence actions, becoming only transiently elevated by the most distal and unexpected reward predictor. Action sequence-related dopamine signaling was reactivated in well-trained rats if they became …

matched on Reward (mesh)

Frontostriatal White Matter Integrity Predicts Development of Delay of Gratification: A Longitudinal Study.

The ability to delay gratification increases considerably across development. Here, we test the hypothesis that this impulse control capacity is driven by increased maturation of frontostriatal circuitry using a fiber-tracking approach combined with longitudinal imaging. In total, 192 healthy volunteers between 8 and 26 years underwent diffusion tensor imaging scanning and completed a delay-discounting task twice, separated by a 2-year interval. We investigated dynamic associations between frontostriatal white matter (WM) integrity and delay of gratification skills. Moreover, we examined the predictive value of frontostriatal WM integrity for future delay of gratification skills. Results showed that delay discounting increases with age in a quadratic fashion, with greatest patience during late adolescence. Data also indicated nonlinear development of frontostriatal WM, with relative fast…

matched on Reward (mesh)

Reward Preferences of Pathological Gamblers Under Conditions of Uncertainty: An Experimental Study.

Among many personality traits, impulsivity represents one of the most important traits associated with pathological gambling. Empirical research has highlighted the multidimensional nature of impulsivity, which includes different heterogeneous traits and behavioral tendencies. The present study experimentally examined reward preferences of pathological gamblers under conditions of uncertainty using the Balloon Analogue Risk Task (BART). Furthermore it also examined the relationship between impulsivity, time perspective, inability to tolerate delay in gratification, and risk-taking. The present study is the first to simultaneously examine all these variables simultaneously in a sample of pathological gamblers (n = 54) and healthy controls (n = 54) from Italy. All participants participated in the BART and were also administered Italian versions of the South Oaks Gambling Screen, the Barrat…

matched on Reward (mesh)

Depression-Related Increases and Decreases in Appetite: Dissociable Patterns of Aberrant Activity in Reward and Interoceptive Neurocircuitry.

Objective: Appetite and weight changes are common but variable diagnostic markers in major depressive disorder: some depressed individuals manifest increased appetite, while others lose their appetite. Many of the brain regions implicated in appetitive responses to food have also been implicated in depression. It is thus remarkable that there exists no published research comparing the neural responses to food stimuli of depressed patients with increased versus decreased appetites. Method: Using functional MRI, brain activity was compared in unmedicated depressed patients with increased or decreased appetite and healthy control subjects while viewing photographs of food and nonfood objects. The authors also measured how resting-state functional connectivity related to subjects' food pleasantness ratings. Results: Within putative reward regions, depressed participants with increased appeti…

matched on Reward (mesh)

Habit formation coincides with shifts in reinforcement representations in the sensorimotor striatum.

Evaluating outcomes of behavior is a central function of the striatum. In circuits engaging the dorsomedial striatum, sensitivity to goal value is accentuated during learning, whereas outcome sensitivity is thought to be minimal in the dorsolateral striatum and its habit-related corticostriatal circuits. However, a distinct population of projection neurons in the dorsolateral striatum exhibits selective sensitivity to rewards. Here, we evaluated the outcome-related signaling in such neurons as rats performed an instructional T-maze task for two rewards. As the rats formed maze-running habits and then changed behavior after reward devaluation, we detected outcome-related spike activity in 116 units out of 1,479 recorded units. During initial training, nearly equal numbers of these units fired preferentially either after rewarded runs or after unrewarded runs, and the majority were respons…

matched on Reward (mesh)

Subsecond dopamine fluctuations in human striatum encode superposed error signals about actual and counterfactual reward.

In the mammalian brain, dopamine is a critical neuromodulator whose actions underlie learning, decision-making, and behavioral control. Degeneration of dopamine neurons causes Parkinson's disease, whereas dysregulation of dopamine signaling is believed to contribute to psychiatric conditions such as schizophrenia, addiction, and depression. Experiments in animal models suggest the hypothesis that dopamine release in human striatum encodes reward prediction errors (RPEs) (the difference between actual and expected outcomes) during ongoing decision-making. Blood oxygen level-dependent (BOLD) imaging experiments in humans support the idea that RPEs are tracked in the striatum; however, BOLD measurements cannot be used to infer the action of any one specific neurotransmitter. We monitored dopamine levels with subsecond temporal resolution in humans (n = 17) with Parkinson's disease while the…

matched on Reward (mesh)

The Power of the Virtual Ideal Self in Weight Control: Weight-Reduced Avatars Can Enhance the Tendency to Delay Gratification and Regulate Dietary Practices.

The tendency to discount larger future benefits in favor of smaller immediate gains (i.e., temporal discounting) is relevant to the issue of obesity. Successful weight loss requires individuals to sacrifice immediate culinary pleasures in favor of future health gains. Based on the notion that increasing the vividness of one's future self may mitigate temporal discounting and promote the ability to delay gratification, we examined whether viewing one's weight-reduced self (i.e., the ideal self) in a virtual environment can decrease temporal discounting and lead to better regulation of dietary practices. Seventy-six undergraduates who had reported an intention to lose weight were recruited to participate in a laboratory experiment and were randomly assigned to interact with either the weight-reduced self (experimental condition) or the present self (control condition) by looking into a dre…

matched on Reward (mesh)

Paralimbic and lateral prefrontal encoding of reward value during intertemporal choice in attempted suicide.

Background: Alongside impulsive suicide attempts, clinicians encounter highly premeditated suicidal acts, particularly in older adults. We have previously found that in contrast to the more impulsive suicide attempters' inability to delay gratification, serious and highly planned suicide attempts were associated with greater willingness to wait for larger rewards. This study examined neural underpinnings of intertemporal preference in suicide attempters. We expected that impulsivity and suicide attempts, particularly poorly planned ones, would predict altered paralimbic subjective value representations. We also examined lateral prefrontal and paralimbic correlates of premeditation in suicidal behavior. Method: A total of 48 participants aged 46-90 years underwent extensive clinical and cognitive characterization and completed the delay discounting task in the scanner: 26 individuals with…

matched on Reward (mesh)

Depressive symptoms and psychosocial aspects of work in bank employees.

Background: The financial sector has seen an increase in the number of cases of violence and stress, which can result in adverse health outcomes, including depressive symptoms, but studies related to stress at work and depression for these workers are scarce. Aims: To investigate the association between exposure to psychosocial work stressors and depressive symptoms in bank employees. Methods: A self-administered questionnaire was completed by a sample of bank employees in Pará and Amapá, Brazil. The survey assessed sociodemographic characteristics, mental health (Patient Health Questionnaire-9), Demand-Control-Support and Effort-Reward Imbalance (ERI). Outcomes included two levels of depressive symptoms: major depressive symptoms (MDS) and other forms of depressive symptoms (ODS). Logistic regression models were used to estimate associations between depressive symptoms, the two job stre…

matched on Reward (mesh)

Trading up: chimpanzees (Pan troglodytes) show self-control through their exchange behavior.

Self-control is defined as the ability or capacity to obtain an objectively more valuable outcome rather than an objectively less valuable outcome though tolerating a longer delay or a greater effort requirement (or both) in obtaining that more valuable outcome. A number of tests have been devised to assess self-control in non-human animals, including exchange tasks. In this study, three chimpanzees (Pan troglodytes) participated in a delay of gratification task that required food exchange as the behavioral response that reflected self-control. The chimpanzees were offered opportunities to inhibit eating and instead exchange a currently possessed food item for a different (and sometimes better) item, often needing to exchange several food items before obtaining the highest valued reward. We manipulated reward type, reward size, reward visibility, delay to exchange, and location of the hi…

matched on Reward (mesh)

Autistic Traits Moderate the Impact of Reward Learning on Social Behaviour.

A deficit in empathy has been suggested to underlie social behavioural atypicalities in autism. A parallel theoretical account proposes that reduced social motivation (i.e., low responsivity to social rewards) can account for the said atypicalities. Recent evidence suggests that autistic traits modulate the link between reward and proxy metrics related to empathy. Using an evaluative conditioning paradigm to associate high and low rewards with faces, a previous study has shown that individuals high in autistic traits show reduced spontaneous facial mimicry of faces associated with high vs. low reward. This observation raises the possibility that autistic traits modulate the magnitude of evaluative conditioning. To test this, we investigated (a) if autistic traits could modulate the ability to implicitly associate a reward value to a social stimulus (reward learning/conditioning, using th…

matched on Reward (mesh)

Optogenetic Activation of Adenosine A2A Receptor Signaling in the Dorsomedial Striatopallidal Neurons Suppresses Goal-Directed Behavior.

The striatum has an essential role in neural control of instrumental behaviors by reinforcement learning. Adenosine A(2A) receptors (A(2A)Rs) are highly enriched in the striatopallidal neurons and are implicated in instrumental behavior control. However, the temporal importance of the A(2A)R signaling in relation to the reward and specific contributions of the striatopallidal A(2A)Rs in the dorsolateral striatum (DLS) and the dorsomedial striatum (DMS) to the control of instrumental learning are not defined. Here, we addressed temporal relationship and sufficiency of transient activation of optoA(2A)R signaling precisely at the time of the reward to the control of instrumental learning, using our newly developed rhodopsin-A2AR chimeras (optoA(2A)R). We demonstrated that transient light activation of optoA(2A)R signaling in the striatopallidal neurons in 'time-locked' manner with the rewa…

matched on Reward (mesh)

A Neurocomputational Model of Altruistic Choice and Its Implications.

We propose a neurocomputational model of altruistic choice and test it using behavioral and fMRI data from a task in which subjects make choices between real monetary prizes for themselves and another. We show that a multi-attribute drift-diffusion model, in which choice results from accumulation of a relative value signal that linearly weights payoffs for self and other, captures key patterns of choice, reaction time, and neural response in ventral striatum, temporoparietal junction, and ventromedial prefrontal cortex. The model generates several novel insights into the nature of altruism. It explains when and why generous choices are slower or faster than selfish choices, and why they produce greater response in TPJ and vmPFC, without invoking competition between automatic and deliberative processes or reward value for generosity. It also predicts that when one's own payoffs are valued…

matched on Reward (mesh)

Attentional impulsivity in binge eating disorder modulates response inhibition performance and frontal brain networks.

Background: A subgroup of overweight and obese people is characterized by binge eating disorder (BED). Increased impulsivity has been suggested to cause binge eating and subsequent weight gain. In the current study, neuronal correlates of increased impulsivity in binge eating disorder during behavioral response inhibition were investigated. Methods: Magnetic brain activity and behavioral responses of 37 overweight and obese individuals with and without diagnosed BED were recorded while performing a food-related visual go-nogo task. Trait impulsivity was assessed with the Barratt Impulsiveness Scale (BIS-11). Results: Specifically, increased attentional impulsiveness (a subscale of the BIS-11) in BED was related to decreased response inhibition performance and hypoactivity in the prefrontal control network, which was activated when response inhibition was required. Furthermore, participan…

matched on Reward (mesh)

On Weight and Waiting: Delay Discounting in Anorexia Nervosa Pretreatment and Posttreatment.

Background: Individuals with anorexia nervosa (AN) override the drive to eat, forgoing immediate rewards in favor of longer-term goals. We examined delay discounting and its neural correlates in AN before and after treatment to test a potential mechanism of illness persistence. Methods: Inpatients with AN (n = 59) and healthy control subjects (HC, n = 39) performed a delay discounting task at two time points. A subset (n = 30 AN, n = 22 HC) participated in functional magnetic resonance imaging scanning during the task. The task consisted of a range of monetary choices with variable delay times, yielding individual discount rates-the rate by which money loses value over time. Results: Before treatment, the AN group showed a preference for delayed over earlier rewards (i.e., less steep discount rates) compared with HC; after weight restoration, AN did not differ from HC. Underweight AN sho…

matched on Reward (mesh)

Disorders of compulsivity: a common bias towards learning habits.

Why do we repeat choices that we know are bad for us? Decision making is characterized by the parallel engagement of two distinct systems, goal-directed and habitual, thought to arise from two computational learning mechanisms, model-based and model-free. The habitual system is a candidate source of pathological fixedness. Using a decision task that measures the contribution to learning of either mechanism, we show a bias towards model-free (habit) acquisition in disorders involving both natural (binge eating) and artificial (methamphetamine) rewards, and obsessive-compulsive disorder. This favoring of model-free learning may underlie the repetitive behaviors that ultimately dominate in these disorders. Further, we show that the habit formation bias is associated with lower gray matter volumes in caudate and medial orbitofrontal cortex. Our findings suggest that the dysfunction in a comm…

matched on Reward (mesh)

Antisocial pool rewarding does not deter public cooperation.

Rewarding cooperation is in many ways expected behaviour from social players. However, strategies that promote antisocial behaviour are also surprisingly common, not just in human societies, but also among eusocial insects and bacteria. Examples include sanctioning of individuals who behave prosocially, or rewarding of free-riders who do not contribute to collective enterprises. We therefore study the public goods game with antisocial and prosocial pool rewarding in order to determine the potential negative consequences on the effectiveness of positive incentives to promote cooperation. Contrary to a naive expectation, we show that the ability of defectors to distribute rewards to their like does not deter public cooperation as long as cooperators are able to do the same. Even in the presence of antisocial rewarding, the spatial selection for cooperation in evolutionary social dilemmas i…

matched on Reward (mesh)

Vulnerability for mania - is it linked to problems delaying gratification?

Impulsivity is described as one of the main risk factors for mania. One facet of impulsivity, the inability to delay gratification, might be of special relevance, because a hypersensitivity to reward is hypothesized to be related to mania. The main aim of this study was to examine whether risk for mania is associated with deficits in the ability to delay gratification using both a behavioral and a self-report (UPPS) measure. An additional reason for choosing the UPPS was to see if prior results about an association between risk for mania and positive urgency could be replicated. Thirty-three individuals at risk for mania and a matched control group were selected using the Hypomanic Personality Scale and interviewed for a history of mood disorders. The main outcome measures were the Single-Key-Impulsivity-Paradigm and Monetary Choice Questionnaire. The groups did not differ in measures of…

matched on Reward (mesh)