skip to main content


Title: Striatal cholinergic receptor activation causes a rapid, selective and state‐dependent rise in cortico‐striatal β activity
Abstract

Cortico‐basal ganglia‐thalamic (CBT) β oscillations (15–30 Hz) are elevated in Parkinson's disease and correlated with movement disability. To date, no experimental paradigm outside of loss of dopamine has been able to specifically elevate β oscillations in theCBTloop. Here, we show that activation of striatal cholinergic receptors selectively increased β oscillations in mouse striatum and motor cortex. In individuals showing simultaneous β increases in both striatum and M1, β partial directed coherence (PDC) increased from striatum to M1 (but not in the reverse direction). In individuals that did not show simultaneous β increases, βPDCincreased from M1 to striatum (but not in the reverse direction), and M1 was characterized by persistent β‐high frequency oscillation phase–amplitude coupling. Finally, the direction of βPDCdistinguished between β sub‐bands. This suggests that (1) striatal cholinergic tone exerts state‐dependent and frequency‐selective control overCBTβ power and coordination; (2) ongoing rhythmic dynamics can determine whether elevated β oscillations are expressed in striatum and M1; and (3) altered striatal cholinergic tone differentially modulates distinct β sub‐bands.

 
more » « less
NSF-PAR ID:
10077842
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
European Journal of Neuroscience
Volume:
48
Issue:
8
ISSN:
0953-816X
Page Range / eLocation ID:
p. 2857-2868
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Abstract

    Dopamine has been implicated in circadian timing underlying the food entrainable oscillator (FEO) circuitry and overexpression of the dopamine D2 receptor (D2R) in the striatum has been reported to reduce motivation to obtain food rewards in operant tasks. In the present study, we explored both of these mechanisms by examining food anticipatory activity (FAA) in dopamine D2 receptor‐overexpressing (D2R‐OE) mice under various durations of food availability. First, we noted that at baseline, there were no differences between D2R‐OEmice and their littermates in activity level, food intake, and body weight or in circadian activity. Under conditions of very restricted food availability (4 or 6 hr), both genotypes displayedFAA. In contrast, under 8‐hr food availability, control mice showedFAA, but D2R‐OEmice did not. Normalization of D2R by administration of doxycycline, a tetracycline analogue, rescuedFAAunder 8‐hr restricted food. We next tested for circadian regulation ofFAA. When given ad libitum access to food, neither D2R‐OEnor controls were active during the daytime. However, after an interval of food restriction, all mice showed elevated locomotor activity at the time of previous food availability in the day, indicating circadian timing of anticipatory activity. In summary, motivation is reduced in D2R‐OEmice but circadian timing behavior is not affected. We conclude that an increase in striatal D2R reducesFAAby modulating motivation and not by acting on a clock mechanism.

     
    more » « less
  2. Abstract

    Maternal presence has marked effects on adolescent neurocognition during risk taking, influencing teenagers to make safer decisions. However, it is currently unknown whether maternal buffering changes over the course of adolescence itself, and whether its effects are robust to individual differences in family relationship quality. In the current longitudinal study, 23 adolescents completed a risk‐taking task under maternal presence during anfMRIscan before and after the transition to high school. Behavioral results reveal that adolescent risk taking increased under maternal presence across a one‐year period. At the neural level, we found that adolescents reporting higher family conflict showed longitudinal increases in functional coupling between the anterior insula (AI) and ventral striatum (VS) when making safe decisions in the presence of their mother, which was associated with increased real‐world risk taking. These findings show that individual differences in family relationship quality undermine effective development ofAIVSconnectivity resulting in increased risk taking.

     
    more » « less
  3. 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 circulatingDHEAlevels are high, and low aggression during molt whenDHEAlevels are low. We previously showed that androgen receptor and aromatasemRNAexpression are higher during breeding and/or nonbreeding in brain regions associated with reproductive and aggressive behaviour, although the potential role ofDHEAin 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.DHEAimplants increased aggression in a laboratory‐based simulated territorial intrusion. Brains ofDHEA‐implanted birds showed higher aromatasemRNAexpression in the preoptic area (POA) and higher androgen receptormRNAexpression in the periventricular nucleus of the medial striatum (pvMSt) and ventromedial nucleus of the hypothalamus. TheDHEA‐induced increases in aromatase expression in thePOAand androgen receptor expression in the pvMSt are consistent with previously reported seasonal increases in these markers associated with naturally elevatedDHEAlevels. This suggests thatDHEAfacilitates seasonal increases in aggression in nonbreeding male song sparrows by up‐regulating steroid signalling/synthesis machinery in a brain region‐specific fashion.

     
    more » « less
  4. Abstract

    The conversion of natural habitats to human land uses often increases local temperatures, creating novel thermal environments for species. The variable responses of ectotherms to habitat conversion, where some species decline while others persist, can partly be explained by variation among species in their thermal niches. However, few studies have examined thermal niche variation within species and across forest‐land use ecotones, information that could provide clues about the capacity of species to adapt to changing temperatures. Here, we quantify individual‐level variation in thermal traits of the tropical poison frog,Oophaga pumilio, in thermally contrasting habitats. Specifically, we examined local environmental temperatures, field body temperatures (Tb), preferred body temperatures (Tpref), critical thermal maxima (CTmax), and thermal safety margins (TSM) of individuals from warm, converted habitats and cool forests. We found that frogs from converted habitats exhibited greater meanTbandTprefthan those from forests. In contrast,CTmaxandTSMdid not differ significantly between habitats. However,CTmaxdid increase moderately with increasingTb, suggesting that changes inCTmaxmay be driven by microscale temperature exposure within habitats rather than by mean habitat conditions. AlthoughO. pumilioexhibited moderate divergence inTpref,CTmaxappears to be less labile between habitats, possibly due to the ability of frogs in converted habitats to maintain theirTbbelow air temperatures that reach or exceedCTmax. Selective pressures on thermal tolerances may increase, however, with the loss of buffering microhabitats and increased frequency of extreme temperatures expected under future habitat degradation and climate warming.

    Abstract in Spanish is available with online material.

     
    more » « less
  5. Abstract

    The local field potential (LFP) is an aggregate measure of group neuronal activity and is often correlated with the action potentials of single neurons. In recent years, investigators have found that action potential firing rates increase during elevations in power high‐frequency band oscillations (50–200 Hz range). However, action potentials also contribute to theLFPsignal itself, making the spike–LFPrelationship complex. Here, we examine the relationship between spike rates andLFPin varying frequency bands in rat neocortical recordings. We find that 50–180 Hz oscillations correlate most consistently with high firing rates, but that otherLFPbands also carry information relating to spiking, including in some cases anti‐correlations. Relatedly, we find that spiking itself and electromyographic activity contribute toLFPpower in these bands. The relationship between spike rates andLFPpower varies between brain states and between individual cells. Finally, we create an improved oscillation‐based predictor of action potential activity by specifically utilizing information from across the entire recorded frequency spectrum ofLFP. The findings illustrate both caveats and improvements to be taken into account in attempts to infer spiking activity fromLFP.

     
    more » « less