The nucleus accumbens core (AcbC) is a key brain region known to regulate the discriminative stimulus/interoceptive effects of alcohol. As such, the goal of the present work was to identify AcbC projection regions that may also modulate sensitivity to alcohol. Accordingly, AcbC afferent projections were identified in behaviorally naïve rats using a retrograde tracer which led to the focus on the medial prefrontal cortex (
Executive function (
- NSF-PAR ID:
- 10041665
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Developmental Science
- Volume:
- 21
- Issue:
- 4
- ISSN:
- 1363-755X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
more » « less
Abstract mPFC ), insular cortex (IC ) and rhomboid thalamic nucleus (Rh). Next, to examine the possible role of these brain regions in modulating sensitivity to alcohol, neuronal response to alcohol in rats trained to discriminate alcohol (1 g/kg, intragastric [IG ]) vs. water was examined using a two‐lever drug discrimination task. As such, rats were administered water or alcohol (1 g/kg,IG ) and brain tissue was processed for c‐Fos immunoreactivity (IR ), a marker of neuronal activity. Alcohol decreased c‐FosIR in themPFC ,IC , Rh and AcbC. Lastly, site‐specific pharmacological inactivation with muscimol + baclofen (GABAA agonist +GABAB agonist) was used to determine the functional role of themPFC ,IC and Rh in modulating the interoceptive effects of alcohol in rats trained to discriminate alcohol (1 g/kg,IG ) vs. water.mPFC inactivation resulted in full substitution for the alcohol training dose, andIC and Rh inactivation produced partial alcohol‐like effects, demonstrating the importance of these regions, with known projections to the AcbC, in modulating sensitivity to alcohol. Together, these data demonstrate a site of action of alcohol and the recruitment of cortical/thalamic regions in modulating sensitivity to the interoceptive effects of alcohol. -
more » « less
Abstract There is growing interest concerning the ways in which the human body, both one's own and that of others, is represented in the developing human brain. In two experiments with 7‐month‐old infants, we employed advances in infant magnetoencephalography (
MEG ) brain imaging to address novel questions concerning body representations in early development. Experiment 1 evaluated the spatiotemporal organization of infants’ brain responses to being touched. A punctate touch to infants’ hands and feet produced significant activation in the hand and foot areas of contralateral primary somatosensory cortex as well as in other parietal and frontal areas. Experiment 2 explored infant brain responses to visually perceiving another person's hand or foot being touched. Results showed significant activation in early visual regions and also in regions thought to be involved in multisensory body and self–other processing. Furthermore, observed touch of the hand and foot activated the infant's own primary somatosensory cortex, although less consistently than felt touch. These findings shed light on aspects of early social cognition, including action imitation, which may build, at least in part, on infant neural representations that map equivalences between the bodies of self and other. -
more » « less
Abstract Atypical neural responses to language have been found in toddlers with autism spectrum disorder (
ASD ) and in their unaffected siblings. However, given that language difficulties are often seen in these children, it is difficult to interpret whether these neural differences are a result of the diagnosis ofASD or impairments in their language abilities. In this study, we recorded event‐related potentials (ERP s) from four groups of 36‐month‐olds: low‐risk control (LRC ), high risk forASD defined as having an older sibling withASD (HRA ) but who do not haveASD or milder autism‐like symptoms (HRA ‐Typ),HRA children who do not haveASD but exhibit milder autism‐like symptoms (HRA ‐Atyp) andHRA children diagnosed withASD (ASD ). Children listened to words expected to be acquired early (e.g. ball) and words expected to be acquired late (e.g. calf).ERP s were analysed over time windows sensitive to word processing as well as frontal and temporo‐parietal sites over the left and right hemispheres. When controlling for language abilities, there were group differences within the temporo‐parietal sites. Specifically, theHRA ‐Atyp group showed a different timed response to late words compared to theASD andLRC groups. In addition, we found a relation between neural responses in the left frontal sites andASD severity. Our results suggest that both language abilities andASD diagnoses are important to consider when interpreting neural differences in lexical processing. -
more » « less
Abstract Oxytocin (
OT ) often regulates social behaviours in sex‐specific ways, and this may be a result of sex differences in the brainOT system. Adult male rats show higherOT receptor (OTR ) binding in the posterior bed nucleus of the stria terminalis (pBNST ) than adult female rats. In the present study, we investigated the mechanisms that lead to this sex difference. First, we found that male rats have higherOTR mRNA expression in thepBNST than females at postnatal day (P) 35 and P60, which demonstrates the presence of the sex difference inOTR binding density at message level. Second, the sex difference inOTR binding density in thepBNST was absent at P0 and P3, but was present by P5. Third, systemic administration of the oestrogen receptor (ER ) antagonist fulvestrant at P0 and P1 dose‐dependently reducedOTR binding density in thepBNST of 5‐week‐old male rats, but did not eliminate the sex difference inOTR binding density. Fourth,pBNST ‐OTR binding density was lower in androgen receptor (AR ) deficient genetic male rats compared to wild‐type males, but higher compared to wild‐type females. Finally, systemic administration of the histone deacetylase inhibitor valproic acid at P0 and P1 did not alterpBNST ‐OTR binding density in 5‐week‐old male and female rats. Interestingly, neonatalER antagonism,AR deficiency, and neonatal valproic acid treatment each eliminated the sex difference inpBNST size. Overall, we demonstrate a role for neonatalER andAR activation in setting up the sex difference inOTR binding density in thepBNST , which may underlie sexual differentiation of thepBNST and social behaviour. -
more » « less
Dehydroepiandrosterone (
DHEA ) is a testosterone/oestrogen precursor and known modulator of vertebrate aggression. Male song sparrows (Melospiza melodia morphna ) show high aggression during breeding and nonbreeding life‐history stages when circulatingDHEA levels are high, and low aggression during molt whenDHEA levels are low. We previously showed that androgen receptor and aromatasemRNA expression are higher during breeding and/or nonbreeding in brain regions associated with reproductive and aggressive behaviour, although the potential role ofDHEA in mediating these seasonal changes remained unclear. In the present study, nonbreeding male song sparrows were captured and held in the laboratory under short days (8 : 16 h light/dark cycle) and implanted with s.c.DHEA ‐filled or empty (control) implants for 14 days.DHEA implants increased aggression in a laboratory‐based simulated territorial intrusion. Brains ofDHEA ‐implanted birds showed higher aromatasemRNA expression in the preoptic area (POA ) and higher androgen receptormRNA expression in the periventricular nucleus of the medial striatum (pvMS t) and ventromedial nucleus of the hypothalamus. TheDHEA ‐induced increases in aromatase expression in thePOA and androgen receptor expression in the pvMS t are consistent with previously reported seasonal increases in these markers associated with naturally elevatedDHEA levels. This suggests thatDHEA facilitates seasonal increases in aggression in nonbreeding male song sparrows by up‐regulating steroid signalling/synthesis machinery in a brain region‐specific fashion.
