In col­lab­o­ra­tion with the IFB Adi­posi­tasErkrankun­gen in Leipzig, we inves­ti­gate flex­i­ble goal-direct­ed deci­sion-mak­ing process­es in a cohort of ado­les­cent and adult obe­si­ty patients with and with­out BED. In this way, we want to sys­tem­at­i­cal­ly dif­fer­en­ti­ate the neu­rocog­ni­tive mech­a­nisms of obe­si­ty and BED in ado­les­cence and adult­hood. We use func­tion­al mag­net­ic res­o­nance imag­ing (fMRI) to probe two cru­cial com­po­nents of goal-direct­ed deci­sion-mak­ing: rever­sal learn­ing and work­ing mem­o­ry updat­ing and main­te­nance. Because alter­ations in dopamin­er­gic sig­nal­ing have pre­vi­ous­ly been impli­cat­ed in goal-direct­ed deci­sion-mak­ing as well as BED and obe­si­ty, we also inves­ti­gate whether these neu­rocog­ni­tive mea­sures are asso­ci­at­ed with genet­ic and imag­ing prox­ies of pre­frontal and stri­atal dopamine function. 

OSF link pre-reg­is­tra­tion: 10.17605/OSF.IO/FYN6Q

Build­ing on find­ings from ani­mal stud­ies we are inter­est­ed in whether a high­er intake of sat­u­rat­ed fats and refined sug­ar is asso­ci­at­ed with dif­fer­ences in dopamine-relat­ed cog­ni­tion. We recruit­ed par­tic­i­pants based on their self-report­ed fat and sug­ar intake, grouped them into low and high con­sumers and com­pared their per­for­mance on five dif­fer­ent cog­ni­tive tasks – two of which were per­formed in the MRI scan­ner. Addi­tion­al­ly, two genet­ic vari­ants relat­ed to dopamine were ana­lyzed and linked to dietary intake and cognition.

key­words: fat, sug­ar, cog­ni­tion, genetics

Link to the pre­reg­is­tra­tion: https://osf.io/vs8cm/

Pre­vi­ous stud­ies sug­gest that there are uncon­scious sig­nals to the reward sys­tem that influ­ence food choice and that are cre­at­ed and main­tained as a con­se­quence of our mod­ern, obe­si­ty-pro­mot­ing envi­ron­ment. To con­firm those results in a Finnish sam­ple, we aim to inves­ti­gate macronu­tri­ent com­bi­na­tions such as car­bo­hy­drates and fat food items and exam­ine their effects on food moti­va­tion. Using a series of food ques­tion­naires (e.g., Dietary Fat and Sug­ar Ques­tion­naire), a behav­ioral task as a proxy for food rein­force­ment, and func­tion­al mag­net­ic res­o­nance (fMRI), we hope to move clos­er to under­stand­ing the effects of mod­ern diets on human eat­ing behav­ior and cog­ni­tion in indi­vid­u­als with a wide range of BMI.

Key­words: macronu­tri­ents, fat, car­bo­hy­drate, reward

Syn­the­sized from dopamine, neu­rome­lanin accu­mu­lates with age. Con­cen­tra­tions of neu­rome­lanin have been shown to cor­re­late to dopamine release. Find­ings in ani­mal stud­ies sug­gest that fol­low­ing a diet high in fat and sug­ar induces dopamin­er­gic changes. How­ev­er, how these alter­ations relate to long-time changes with­in the brain’s dopamin­er­gic path­ways is not known, and there­fore we inves­ti­gate whether a high­er intake of sat­u­rat­ed fats and refined sug­ar is asso­ci­at­ed with dif­fer­ences in neu­rome­lanin con­cen­tra­tion in humans. We do this using quan­ti­ta­tive sus­cep­ti­bil­i­ty map­ping (QSM), an MRI tech­nique that is sen­si­tive to para­mag­net­ic substances.

This col­lab­o­ra­tion project with the Depart­ment of Eco­nom­ics at the Uni­ver­si­ty of Zurich employs func­tion­al mag­net­ic res­o­nance imag­ing (fMRI)-based neu­ro­feed­back from human SN/VTA mid­brain nuclei. Based on their assumed role in moti­va­tion, this project inves­ti­gates the link between (vol­un­tary) BOLD sig­nal fluc­tu­a­tions with­in these areas and changes in cost-ben­e­fit decision-making. 

Key­words: dopamine, mid­brain, neu­ro­feed­back, deci­sion-mak­ing, men­tal effort

In 2010, a break­through study by Lal­ly and col­leagues titled How are habits formed: Mod­el­ing habit for­ma­tion in the real world found that on aver­age it takes peo­ple 66 days to form a healthy habit. This study has been cit­ed more than 2000 times, inspired a line of research into real-world habit for­ma­tion, and influ­enced pub­lic occu­pa­tion­al health, busi­ness eco­nom­ics, and sci­ence tech­nol­o­gy around the globe. In an inter­na­tion­al coop­er­a­tion with the uni­ver­si­ties of Ams­ter­dam, NL, Cam­bridge, UK, and Kon­stanz, GER and led by Dr Sanne de Wit we aim to repli­cate the study’s find­ing and extend it to a broad­er population.

key­words: habit for­ma­tion, replication

We are cur­rent­ly look­ing for participants!