Article

Do rats have a prefrontal cortex?

Netherlands Institute for Brain Research, KNAW, Graduate School Neurosciences, Meibergdreef 33, 1105 AZ, Amsterdam, The Netherlands.
Behavioural Brain Research (Impact Factor: 3.39). 12/2003; 146(1-2):3-17. DOI: 10.1016/j.bbr.2003.09.028
Source: PubMed

ABSTRACT The lack of a single anatomical or functional definition of 'prefrontal cortex' has led to different and, in some respects, controversial views on the existence of a prefrontal cortex in non-primate mammals, in particular in rats. Until the classic paper by Rose and Woolsey [Res. Publ. Assoc. Nerv. Ment. Dis. 27 (1948) 210], the general idea was that a prefrontal cortex is unique to primate species. Rose and Woolsey's 'prefrontal cortex' definition was based upon a single anatomical criterion, i.e. the cortical projection area of the mediodorsal thalamic nucleus. Single criteria, however, do not appear to be sufficient for defining the prefrontal cortex. Therefore, other anatomical and functional characteristics are currently used to identify the prefrontal cortex in different species. Yet, recently the debate about the nature of the prefrontal cortex in non-primate species has been resumed. In the present paper we will compare the structural and functional characteristics of the prefrontal cortex of nonhuman primates and rats. We will argue that rats have a functionally divided prefrontal cortex that includes not only features of the medial and orbital areas in primates, but also some features of the primate dorsolateral prefrontal cortex.

0 Followers
 · 
207 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study we sought to determine the effect of daily sucrose consumption in young rats on their subsequent performance in tasks that involve the prefrontal cortex and hippocampus. High levels of sugar consumption have been associated with the development of obesity, however less is known about how sugar consumption influences behavioral control and high-order cognitive processes. Of particular concern is the fact that sugar intake is greatest in adolescence, an important neurodevelopmental period. We provided sucrose to rats when they were progressing through puberty and adolescence. Cognitive performance was assessed in adulthood on a task related to executive function, a rodent analog of the Stroop task. We found that sucrose-exposed rats failed to show context-appropriate responding during incongruent stimulus compounds presented at test, indicative of impairments in prefrontal cortex function. Sucrose exposed rats also showed deficits in an on object-in-place recognition memory task, indicating that both prefrontal and hippocampal function was impaired. Analysis of brains showed a reduction in expression of parvalbumin-immunoreactive GABAergic interneurons in the hippocampus and prefrontal cortex, indicating that sucrose consumption during adolescence induced long-term pathology, potentially underpinning the cognitive deficits observed. These results suggest that consumption of high levels of sugar-sweetened beverages by adolescents may also impair neurocognitive functions affecting decision-making and memory, potentially rendering them at risk for developing mental health disorders. © 2015 Reichelt et al.; Published by Cold Spring Harbor Laboratory Press.
    Learning & memory (Cold Spring Harbor, N.Y.) 04/2015; 22(4):215-24. DOI:10.1101/lm.038000.114 · 4.38 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Sex- and season-specific modulation of hippocampal size and function is observed across multiple species, including rodents. Other non-hippocampal-dependent behaviors exhibit season and sex differences, and whether the associated brain regions exhibit similar variation with sex and season remains to be fully characterized. As such, we examined the brains of wild-caught Richardson’s ground squirrels (RGS; Urocitellus richardsonii) for seasonal (breeding, non-breeding) and sex differences in the volumes of specific brain areas, including: total brain volume, corpus callosum (CC), anterior commissure (AC), medial prefrontal cortex (mPFC), total neocortex (NC), entorhinal cortex (EC), and superior colliculus (SC). Analyses of variance and covariance revealed significant interactions between season and sex for almost all areas studied, primarily resulting from females captured during the breeding season exhibiting larger volumes than females captured during the non-breeding season. This was observed for volumes of the AC, mPFC, NC, EC, and SC. Where simple main effects of season were observed for males (the NC and the SC), the volume advantage favoured males captured during the NBr season. Only two simple main effects of sex were observed: males captured in the non-breeding season had significantly larger total brain volume than females captured in the non-breeding season, and females captured during the breeding season had larger volumes of the mPFC and EC than males captured in the breeding season. These results indicate that females have more pronounced seasonal differences in brain and brain region sizes. The extent to which seasonal differences in brain region volumes vary with behaviour is unclear, but our data do suggest that seasonal plasticity is not limited to the hippocampus and that RGS is a useful mammalian species for understanding seasonal plasticity in an ecologically relevant context.
    Neuroscience 01/2015; 289. DOI:10.1016/j.neuroscience.2014.12.077 · 3.33 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hippocampal-prefrontal interactions are implicated in working memory (WM) and altered in psychiatric conditions with cognitive impairment such as schizophrenia. While coupling between both structures is crucial for WM performance in rodents, evidence from human studies is conflicting and translation of findings is complicated by the use of differing paradigms across species. We therefore used functional magnetic resonance imaging (fMRI) together with a spatial WM paradigm adapted from rodent research to examine hippocampal-prefrontal coupling in humans. A prefrontal-parietal network was functionally connected to hippocampus (HC) during task stages requiring high levels of executive control but not during a matched control condition. The magnitude of coupling in a network comprising HC, bilateral dorsolateral prefrontal cortex (DLPFC) and right supramarginal gyrus explained one fourth of the variability in an independent spatial WM task but was unrelated to visual WM performance. HC-DLPFC coupling may thus represent a systems-level mechanism specific to spatial WM that is conserved across species, suggesting its utility for modeling cognitive dysfunction in translational neuroscience.Neuropsychopharmacology accepted article preview online, 12 January 2015. doi:10.1038/npp.2015.13.
    Neuropsychopharmacology: official publication of the American College of Neuropsychopharmacology 01/2015; DOI:10.1038/npp.2015.13 · 7.83 Impact Factor