TY  - CHAP
A1  - Heinz, A.
A1  - Kluge, U.
A1  - Schouler-Ocak, M.
A1  - Rapp, Michael Armin
T1  - Biological Effects of Social Exclusion
T2  - European psychiatry : the journal of the Association of European Psychiatrists
N2  - Timing and magnitude of surface uplift are key to understanding the impact of crustal deformation and topographic growth on atmospheric circulation, environmental conditions, and surface processes. Uplift of the East African Plateau is linked to mantle processes, but paleoaltimetry data are too scarce to constrain plateau evolution and subsequent vertical motions associated with rifting. Here, we assess the paleotopographic implications of a beaked whale fossil (Ziphiidae) from the Turkana region of Kenya found 740 km inland from the present-day coastline of the Indian Ocean at an elevation of 620 m. The specimen is similar to 17 My old and represents the oldest derived beaked whale known, consistent with molecular estimates of the emergence of modern straptoothed whales (Mesoplodon). The whale traveled from the Indian Ocean inland along an eastward-directed drainage system controlled by the Cretaceous Anza Graben and was stranded slightly above sea level. Surface uplift from near sea level coincides with paleoclimatic change from a humid environment to highly variable and much drier conditions, which altered biotic communities and drove evolution in east Africa, including that of primates.
Y1  - 2015
SN  - 0924-9338
SN  - 1778-3585
VL  - 30
PB  - Elsevier
CY  - Paris
ER  - 
TY  - JOUR
A1  - Deserno, Lorenz
A1  - Beck, Anne
A1  - Huys, Quentin J. M.
A1  - Lorenz, Robert C.
A1  - Buchert, Ralph
A1  - Buchholz, Hans-Georg
A1  - Plotkin, Michail
A1  - Kumakara, Yoshitaka
A1  - Cumming, Paul
A1  - Heinze, Hans-Jochen
A1  - Grace, Anthony A.
A1  - Rapp, Michael Armin
A1  - Schlagenhauf, Florian
A1  - Heinz, Andreas
T1  - Chronic alcohol intake abolishes the relationship between dopamine synthesis capacity and learning signals in the ventral striatum
JF  - European journal of neuroscience
N2  - Drugs of abuse elicit dopamine release in the ventral striatum, possibly biasing dopamine-driven reinforcement learning towards drug-related reward at the expense of non-drug-related reward. Indeed, in alcohol-dependent patients, reactivity in dopaminergic target areas is shifted from non-drug-related stimuli towards drug-related stimuli. Such hijacked' dopamine signals may impair flexible learning from non-drug-related rewards, and thus promote craving for the drug of abuse. Here, we used functional magnetic resonance imaging to measure ventral striatal activation by reward prediction errors (RPEs) during a probabilistic reversal learning task in recently detoxified alcohol-dependent patients and healthy controls (N=27). All participants also underwent 6-[F-18]fluoro-DOPA positron emission tomography to assess ventral striatal dopamine synthesis capacity. Neither ventral striatal activation by RPEs nor striatal dopamine synthesis capacity differed between groups. However, ventral striatal coding of RPEs correlated inversely with craving in patients. Furthermore, we found a negative correlation between ventral striatal coding of RPEs and dopamine synthesis capacity in healthy controls, but not in alcohol-dependent patients. Moderator analyses showed that the magnitude of the association between dopamine synthesis capacity and RPE coding depended on the amount of chronic, habitual alcohol intake. Despite the relatively small sample size, a power analysis supports the reported results. Using a multimodal imaging approach, this study suggests that dopaminergic modulation of neural learning signals is disrupted in alcohol dependence in proportion to long-term alcohol intake of patients. Alcohol intake may perpetuate itself by interfering with dopaminergic modulation of neural learning signals in the ventral striatum, thus increasing craving for habitual drug intake.
KW  - alcohol addiction
KW  - dopamine
KW  - fMRI
KW  - PET
KW  - prediction error
Y1  - 2015
U6  - https://doi.org/10.1111/ejn.12802
SN  - 0953-816X
SN  - 1460-9568
VL  - 41
IS  - 4
SP  - 477
EP  - 486
PB  - Wiley-Blackwell
CY  - Hoboken
ER  -