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Lauerma, H.

Publications and source records attributed to Lauerma, H..

4 recordsLinked to original sources

Dopamine D2R and opioid MOR availability in autism spectrum disorder

Opioid and dopamine receptor systems are implicated in the pathoetiology of autism, but in vivo human brain imaging evidence for their role remains elusive. Here, we investigated regional type 2 dopamine and mu-opioid receptor (D2R and MOR, respectively) availabilities and regional interactions between the two neuromodulatory systems associated with autism spectrum disorder (ASD). In vivo positron emission tomography (PET) with radioligands [11C]raclopride (D2R) and [11C]carfentanil (MOR) was carried out in 16 adult males with high functioning ASD and 19 age and sex matched controls. Regional group differences in D2R and MOR receptor availabilities were tested with linear mixed models and associations between regional receptor availabilities were examined with correlations. There were no group differences in whole-brain voxel-wise analysis of DR2 but ROI analysis presented a lower overall mean D2R availability in striatum of the ASD versus control group. Post hoc regional analysis revealed reduced D2R availability in nucleus accumbens of the ASD group. The whole-brain voxel-wise analysis of MOR revealed precuneal up-regulation in the ASD group, but there was no overall group difference in the ROI analysis for MOR. MOR down-regulation was observed in the hippocampi of the ASD group in a post hoc analysis. Regional correlations between D2R and MOR availabilities were weaker in the ASD group versus control group in the amygdala and nucleus accumbens. These alterations may translate to disrupted modulation of social motivation and reward in ASD.

neuroscience↗

Aberrant type 2 dopamine receptor availability in criminal psychopathy

BackgroundPsychopathy is characterized by antisocial behavior, poor behavioral control and lacking empathy, and structural alterations in the corresponding neural circuits. Molecular brain basis of psychopathy remains poorly characterized. MethodsHere we studied type 2 dopamine receptor (D2R) and mu-opioid receptor (MOR) availability in convicted violent offenders with high psychopathic traits (n=11) and healthy matched controls (n=19) using positron emission tomography (PET). D2R were measured with radioligand [11C]raclopride and MORs with radioligand [11C]carfentanil. ResultsPsychopathic subjects had lowered D2R availability in caudate and putamen, and D2R striatal availability was also associated with degree of psychopathic traits in this prisoner sample. No group differences were found in MOR availability, although in the prisoner sample, psychopathic traits were negatively correlated with MOR availability amygdala and nucleus accumbens. ConclusionsWe conclude that D2R signaling could be the putative neuromolecular pathway for psychopathy, whereas evidence for the aberrant MOR system is more limited.

neuroscience↗

Mu-opioid receptor system modulates responses to vocal bonding and distress signals in humans

Laughter is a contagious prosocial signal that conveys bonding motivation; adult crying conversely communicates desire for social proximity by signalling distress. Endogenous mu-opioid receptors (MORs) modulate sociability in humans and non-human primates. In this combined PET-fMRI study (n=17) we tested whether central MOR tone is associated with regional brain responses to social signals of laughter and crying sounds. MOR availability was measured with positron emission tomography using high-affinity agonist radioligand [11C]carfentanil. Haemodynamic responses to social laughter and crying sounds were measured using functional magnetic resonance imaging (fMRI). Social laughter evoked activation in the auditory cortex, insula, cingulate cortex, amygdala, primary and secondary somatosensory cortex, primary and secondary motor cortex; crying sounds led to more restricted activation in auditory cortex and nearby areas. MOR availability was negatively correlated with the haemodynamic responses to social laughter in primary and secondary somatosensory cortex, primary and secondary motor cortex, posterior insula, posterior cingulate cortex, precuneus, cuneus, temporal gyri, and lingual gyrus. For crying-evoked activations, MOR availability was negatively correlated with medial and lateral prefrontal haemodynamic responses. Altogether our findings highlight the role of MOR system in modulating acute brain responses to both positive and negative social signals.

neuroscience↗

Aberrant motor contagion of emotions in psychopathy and high-functioning autism

Psychopathy and autism are both associated with aberrant social interaction and communication, yet only psychopaths are markedly antisocial and violent. Here we compared the functional neural alterations underlying these two different phenotypes with distinct patterns of socioemotional difficulties. We studied 19 incarcerated male offenders with high psychopathic traits, 20 males with high-functioning autism and 19 age-matched healthy controls. All groups underwent functional magnetic resonance imaging while they viewed dynamic happy, angry and disgust facial expressions or listened to laughter and crying sounds. Psychopathy was associated with reduced somatomotor responses to almost all expressions, while subjects with autism demonstrated less marked and emotion-specific alterations in the somatomotor area. These data suggest that psychopathy and autism involve both common and distinct functional alterations in the brain networks involved in socioemotional processing.

neuroscience↗