Behavioral response to methylphenidate challenge: Influence of early life parental care

Abstract

Rat studies have shown that pups subjected to suboptimal rearing conditions exhibited permanently dysregulated dopamine activity and altered behavioral responses to dopamine stimulation. In humans, heightened stress-induced mesoaccumbens dopamine release in adults reporting low maternal care experience has been shown. We explored the relationship between quality of parental care and behavioral responsivity to reward and 20 mg of the dopamine agonist methylphenidate (MPH). Forty-three male university students accomplished a monetarily rewarded card-sorting task in a placebo controlled between-subjects study design. In participants scoring above the cut-off score for high parental care as assessed by the Parental Bonding Inventory, MPH decreased performance accuracy in the reward condition of the task. Contrarily, reward-induced performance accuracy of low care participants was enhanced with MPH. Activity measures in response to reward and MPH were uninfluenced by parental care. This is the first human study to reveal that the behavioral MPH response interacts with early life parental care experience.

Perceived early-life maternal care and the cortisol response to repeated psychosocial stress

“…14 In an elderly population, we showed an association between low early-life parental care (including mother and father care ratings), decreased hippocampal volume and self-esteem and an increased cortisol response to the Montreal Imaging Stress Task (MIST). 15 Further studies from our group have extended these findings by revealing an influence of early-life maternal care on hippocampal volume in young adult women 16 and an influence of earlylife parental care on the cortisol awakening response 17 and the behavioural response to methylphenidate 18 in young adults. In the current study, we investigated the influence of earlylife maternal care on single and repeated TSST exposure.…”

“…The cluster analysis identified low (n = 15; mean care 16.33, SD 2.72, range [11][12][13][14][15][16][17][18][19][20], medium (n = 19; mean care 24.74, SD 2.10, range 22-28) and high (n = 29; mean care 32.52, SD 2.21, range 29-36) maternal care groups. Two of the 63 participants (both from the low maternal care group) reported separation of their parents.…”

“…We have repeatedly found similar associations in earlier studies comparing low and high parental care groups. 14,18 When comparing the medium with the high maternal care group (whereby the mean maternal care score of the medium care group lay below Parker's 20 cut-off score for high care), the expected negative linear relation between care and cortisol stress responsivity did become apparent. It could thus be argued that our initial hypothesis was not completely falsified, and that the relatively increased cortisol stress response in the medium maternal care group indicates a higher probability to process everyday stressors as a threat to the self.…”

Increased cortisol awakening response and afternoon/evening cortisol output in healthy young adults with low early life parental care

“…Among numerous psychological variables, depression (or symptoms of depressed mood) and anxiety have been shown to be associated with the CAR (Chida and Steptoe 2009;Fries et al 2009) and different measures of diurnal cortisol levels (den Hartog et al 2003;Giese-Davis et al 2004; Van den Bergh et al 2008;Vreeburg et al 2009). Moreover, lower self-esteem and higher levels of depressive symptomatology and anxiety were found in participants with low parental care experiences (Engert et al 2009(Engert et al , 2010. To allow for the examination of group differences in these psychological variables, we used the Rosenberg Self-Esteem Scale (RSES; Rosenberg 1989) to measure self-esteem, the Beck Depression Inventory (BDI; Beck 1987) to measure characteristic attitudes and symptoms of depression and the trait scale of the State-Trait Anxiety Inventory (STAI; Spielberger 1983) to measure symptoms of anxiety.…”

DATby perceived MC interaction on human prefrontal activity and connectivity during emotion processing

“…This questionnaire uses a cut-off score of 27 to discriminate subjects with 'high' and 'low' MC Parker and Lipscombe, 1979) and has been utilized as such in several previous studies (Pruessner et al, 2004;Buss et al, 2007;Engert et al, 2009;Pruessner et al, 2010). Moreover, in the original studies by Parker et al (Parker and Brown, 1979;Parker, 1983Parker, , 1989Parker, , 1990) factor analytic strategies were used to identify PBI items that best defined and refined parental dimensions.…”