The Experts below are selected from a list of 57 Experts worldwide ranked by ideXlab platform
Asla Pitkanen - One of the best experts on this subject based on the ideXlab platform.
-
projections from the Periamygdaloid Cortex to the amygdaloid complex the hippocampal formation and the parahippocampal region a pha l study in the rat
Hippocampus, 2003Co-Authors: Katarzyna Majak, Asla PitkanenAbstract:The Periamygdaloid Cortex, an amygdaloid region that processes olfactory information, projects to the hippocampal formation and parahippocampal region. To elucidate the topographic details of these projections, pathways were anterogradely traced using Phaseolus vulgaris leukoagglutinin (PHA-L) in 14 rats. First, we investigated the intradivisional, interdivisional, and intra-amygdaloid connections of various subfields [Periamygdaloid subfield (PAC), medial subfield (PACm), sulcal subfield (PACs)] of the Periamygdaloid Cortex. Thereafter, we focused on projections to the hippocampal formation (dentate gyrus, hippocampus proper, subiculum) and to the parahippocampal region (presubiculum, parasubiculum, entorhinal, and perirhinal and postrhinal cortices). The PACm had the heaviest intradivisional projections and it also originated light interdivisional projections to other Periamygdaloid subfields. Projections from the other subfields converged in the PACs. All subfields provided substantial intra-amygdaloid projections to the medial and posterior cortical nuclei. In addition, the PAC subfield projected to the ventrolateral and medial divisions of the lateral nucleus. The heaviest periamygdalohippocampal projections originated in the PACm and PACs, which projected moderately to the temporal end of the stratum lacunosum moleculare of the CA1 subfield and to the molecular layer of the ventral subiculum. The PACm also projected moderately to the temporal CA3 subfield. The heaviest projections to the entorhinal Cortex originated in the PACs and terminated in the amygdalo-entorhinal, ventral intermediate, and medial subfields. Area 35 of the perirhinal Cortex was lightly innervated by the PAC subfield. Thus, these connections might allow for olfactory information entering the amygdala to become associated with signals from other sensory modalities that enter the amygdala via other nuclei. Further, the periamygdalohippocampal pathways might form one route by which the amygdala modulates memory formation and retrieval in the medial temporal lobe memory system. These pathways can also facilitate the spread of seizure activity from the amygdala to the hippocampal and parahippocampal regions in temporal lobe epilepsy. © 2003 Wiley-Liss, Inc.
-
projections from the posterior cortical nucleus of the amygdala to the hippocampal formation and parahippocampal region in rat
Hippocampus, 2002Co-Authors: Samuli Kemppainen, Esa Jolkkonen, Asla PitkanenAbstract:The posterior cortical nucleus of the amygdala is involved in the processing of pheromonal information and presumably participates in ingestive, defensive, and reproductive behaviors as a part of the vomeronasal amygdala. Recent studies suggest that the posterior cortical nucleus might also modulate memory processing via its connections to the medial temporal lobe memory system. To investigate the projections from the posterior cortical nucleus to the hippocampal formation and the parahippocampal region, as well as the intra-amygdaloid connectivity in detail, we injected the anterograde tracer phaseolus vulgaris-leucoagglutinin into different rostrocaudal levels of the posterior cortical nucleus. Within the hippocampal formation, the stratum lacunosum-moleculare of the temporal CA1 subfield and the adjacent molecular layer of the proximal temporal subiculum received a moderate projection. Within the parahippocampal region, the ventral intermediate, dorsal intermediate, and medial subfields of the entorhinal Cortex received light to moderate projections. Most of the labeled terminals were in layers I, II, and III. In the ventral intermediate subfield, layers V and VI were also moderately innervated. Layers I and II of the parasubiculum received a light projection. There were no projections to the presubiculum or to the perirhinal and postrhinal cortices. The heaviest intranuclear projection was directed to the deep part of layer I and to layer II of the posterior cortical nucleus. There were moderate-to-heavy intra-amygdaloid projections terminating in the bed nucleus of the accessory olfactory tract, the central division of the medial nucleus, and the sulcal division of the Periamygdaloid Cortex. Our data suggest that via these topographically organized projections, pheromonal information processed within the posterior cortical nucleus can influence memory formation in the hippocampal and parahippocampal areas. Also, these pathways provide routes through which seizure activity can spread from the epileptic amygdala to the surrounding region of the temporal lobe. Hippocampus 2002;12:735–755. © 2002 Wiley-Liss, Inc.
-
topographic projections from the Periamygdaloid Cortex to select subregions of the lateral nucleus of the amygdala in the rat
Neuroscience Letters, 1996Co-Authors: Vesa Savander, Joseph E. Ledoux, Asla PitkanenAbstract:Information from most of the sensory modalities enters the amygdala via the lateral nucleus. The olfactory information, however, arrives at the amygdala through the superficial nuclei, including the Periamygdaloid Cortex. To find out whether the olfactory information can modulate the processing of sensory information in the lateral nucleus we injected Phaseolus vulgaris leucoagglutinin, an anterograde axonal tracer, into the different divisions of the Periamygdaloid Cortex. We found that the PAC division of the Periamygdaloid Cortex projects to the ventrolateral and medial divisions, but not the dorsolateral division, of the lateral amygdaloid nucleus. Therefore, the projection from the PAC to the lateral nucleus provides a route, by which the olfactory information may become associated with other sensory modalities. Also, together with our previous finding that the lateral nucleus projects to the Periamygdaloid Cortex, the present data demonstrate that the lateral nucleus and the PAC are reciprocally connected.
Joseph L Price - One of the best experts on this subject based on the ideXlab platform.
-
limbic connections of the orbital and medial prefrontal Cortex in macaque monkeys
The Journal of Comparative Neurology, 1995Co-Authors: S T Carmichael, Joseph L PriceAbstract:Previous studies have shown that the orbital and medial prefrontal Cortex (OMPFC) is extensively connected with medial temporal and cingulate limbic structures. In this study, the organization of these projections was defined in relation to architectonic areas within the OMPFC. All of the limbic structures were substantially connected with the following posterior and medial orbital areas: the posteromedial, medial, intermediate, and lateral agranular insular areas (Iapm, Iam, Iai, and Ial, respectively) and areas 11m, 13a, 13b, 14c, and 14r. In contrast, lateral orbital areas 12o, 12m, and [12] and medial wall areas 24a, b and 32 were primarily connected with the amygdala, the temporal pole, and the cingulate Cortex. Data were not obtained on the poateroventral medial wall. Three distinct projections were recognized from the basal amygdaloid nucleus: (1) The dorsal part projected to area 121; (2) the ventromedial part projected to most areas in the posterior and medial orbital Cortex except for areas Iai, 12o, 13a, and 14c; and (3) the ventrolateral part projected to orbital areas 12o, Iai, 13a, 14c, and to the medial wall areas. The accessory basal and lateral amygdaloid nuclei projected most strongly to areas in the posterior and medial orbital Cortex. The medial, anterior cortical, and central amygdaloid nuclei and the Periamygdaloid Cortex were connected with the posterior orbital areas. The projection from the hippocampus originated from the rostral subiculum and terminated in the medial orbital areas. The same region was reciprocally connected with the anterornedial nucleus of the thalamus, which received input from the rostral subiculum. The parahippocampal cortical areas (including the temporal polar, entorhinal, perirhinal, and posterior parahippocampal cortices) were primarily connected with posterior and medial orbital areas, with some projections to the dorsal parr of the medial wall. The rostral cingulate Cortex sent fibers to the medial wall, to the medial orbital areas, and to lateral areas 12o, 12r, and Iai. The posterior cingulate gyrus, including the caudomedial lobule, was especially strongly connected with area 11 m. © 1995 Wiley-Liss, Inc.
-
limbic connections of the orbital and medial prefrontal Cortex in macaque monkeys
The Journal of Comparative Neurology, 1995Co-Authors: S T Carmichael, Joseph L PriceAbstract:Previous studies have shown that the orbital and medial prefrontal Cortex (OMPFC) is extensively connected with medial temporal and cingulate limbic structures. In this study, the organization of these projections was defined in relation to architectonic areas within the OMPFC. All of the limbic structures were substantially connected with the following posterior and medial orbital areas: the posteromedial, medial, intermediate, and lateral agranular insular areas (Iapm, Iam, Iai, and Ial, respectively) and areas 11m, 13a, 13b, 14c and 14r. In contrast, lateral orbital areas 12o, 12m, and 12l and medial wall areas 24a,b and 32 were primarily connected with the amygdala, the temporal pole, and the cingulate Cortex. Data were not obtained on the posteroventral medial wall. Three distinct projections were recognized from the basal amygdaloid nucleus: 1) The dorsal part projected to area 12l; 2) the ventromedial part projected to most areas in the posterior and medial orbital Cortex except for area Iai, 12o, 13a, and 14c; and 3) the ventrolateral part projected to orbital areas 12o, Iai, 13a, 14c, and to the medial wall areas. The accessory basal and lateral amygdaloid nuclei projected most strongly to areas in the posterior and medial orbital Cortex. The medial, anterior cortical, and central amygdaloid nuclei and the Periamygdaloid Cortex were connected with the posterior orbital areas. The projection from the hippocampus originated from the rostral subiculum and terminated in the medial orbital areas. The same region was reciprocally connected with the anteromedial nucleus of the thalamus, which received input from the rostral subiculum. The parahippocampal cortical areas (including the temporal polar, entorhinal, perirhinal, and posterior parahippocampal cortices) were primarily connected with posterior and medial orbital areas, with some projections to the dorsal part of the medial wall. The rostral cingulate Cortex sent fibers to the medial wall, to the medial orbital areas, and to lateral areas 12o, 12r, and Iai. The posterior cingulate gyrus, including the caudomedial lobule, was especially strongly connected with area 11m.
S T Carmichael - One of the best experts on this subject based on the ideXlab platform.
-
limbic connections of the orbital and medial prefrontal Cortex in macaque monkeys
The Journal of Comparative Neurology, 1995Co-Authors: S T Carmichael, Joseph L PriceAbstract:Previous studies have shown that the orbital and medial prefrontal Cortex (OMPFC) is extensively connected with medial temporal and cingulate limbic structures. In this study, the organization of these projections was defined in relation to architectonic areas within the OMPFC. All of the limbic structures were substantially connected with the following posterior and medial orbital areas: the posteromedial, medial, intermediate, and lateral agranular insular areas (Iapm, Iam, Iai, and Ial, respectively) and areas 11m, 13a, 13b, 14c, and 14r. In contrast, lateral orbital areas 12o, 12m, and [12] and medial wall areas 24a, b and 32 were primarily connected with the amygdala, the temporal pole, and the cingulate Cortex. Data were not obtained on the poateroventral medial wall. Three distinct projections were recognized from the basal amygdaloid nucleus: (1) The dorsal part projected to area 121; (2) the ventromedial part projected to most areas in the posterior and medial orbital Cortex except for areas Iai, 12o, 13a, and 14c; and (3) the ventrolateral part projected to orbital areas 12o, Iai, 13a, 14c, and to the medial wall areas. The accessory basal and lateral amygdaloid nuclei projected most strongly to areas in the posterior and medial orbital Cortex. The medial, anterior cortical, and central amygdaloid nuclei and the Periamygdaloid Cortex were connected with the posterior orbital areas. The projection from the hippocampus originated from the rostral subiculum and terminated in the medial orbital areas. The same region was reciprocally connected with the anterornedial nucleus of the thalamus, which received input from the rostral subiculum. The parahippocampal cortical areas (including the temporal polar, entorhinal, perirhinal, and posterior parahippocampal cortices) were primarily connected with posterior and medial orbital areas, with some projections to the dorsal parr of the medial wall. The rostral cingulate Cortex sent fibers to the medial wall, to the medial orbital areas, and to lateral areas 12o, 12r, and Iai. The posterior cingulate gyrus, including the caudomedial lobule, was especially strongly connected with area 11 m. © 1995 Wiley-Liss, Inc.
-
limbic connections of the orbital and medial prefrontal Cortex in macaque monkeys
The Journal of Comparative Neurology, 1995Co-Authors: S T Carmichael, Joseph L PriceAbstract:Previous studies have shown that the orbital and medial prefrontal Cortex (OMPFC) is extensively connected with medial temporal and cingulate limbic structures. In this study, the organization of these projections was defined in relation to architectonic areas within the OMPFC. All of the limbic structures were substantially connected with the following posterior and medial orbital areas: the posteromedial, medial, intermediate, and lateral agranular insular areas (Iapm, Iam, Iai, and Ial, respectively) and areas 11m, 13a, 13b, 14c and 14r. In contrast, lateral orbital areas 12o, 12m, and 12l and medial wall areas 24a,b and 32 were primarily connected with the amygdala, the temporal pole, and the cingulate Cortex. Data were not obtained on the posteroventral medial wall. Three distinct projections were recognized from the basal amygdaloid nucleus: 1) The dorsal part projected to area 12l; 2) the ventromedial part projected to most areas in the posterior and medial orbital Cortex except for area Iai, 12o, 13a, and 14c; and 3) the ventrolateral part projected to orbital areas 12o, Iai, 13a, 14c, and to the medial wall areas. The accessory basal and lateral amygdaloid nuclei projected most strongly to areas in the posterior and medial orbital Cortex. The medial, anterior cortical, and central amygdaloid nuclei and the Periamygdaloid Cortex were connected with the posterior orbital areas. The projection from the hippocampus originated from the rostral subiculum and terminated in the medial orbital areas. The same region was reciprocally connected with the anteromedial nucleus of the thalamus, which received input from the rostral subiculum. The parahippocampal cortical areas (including the temporal polar, entorhinal, perirhinal, and posterior parahippocampal cortices) were primarily connected with posterior and medial orbital areas, with some projections to the dorsal part of the medial wall. The rostral cingulate Cortex sent fibers to the medial wall, to the medial orbital areas, and to lateral areas 12o, 12r, and Iai. The posterior cingulate gyrus, including the caudomedial lobule, was especially strongly connected with area 11m.
Katarzyna Majak - One of the best experts on this subject based on the ideXlab platform.
-
projections from the Periamygdaloid Cortex to the amygdaloid complex the hippocampal formation and the parahippocampal region a pha l study in the rat
Hippocampus, 2003Co-Authors: Katarzyna Majak, Asla PitkanenAbstract:The Periamygdaloid Cortex, an amygdaloid region that processes olfactory information, projects to the hippocampal formation and parahippocampal region. To elucidate the topographic details of these projections, pathways were anterogradely traced using Phaseolus vulgaris leukoagglutinin (PHA-L) in 14 rats. First, we investigated the intradivisional, interdivisional, and intra-amygdaloid connections of various subfields [Periamygdaloid subfield (PAC), medial subfield (PACm), sulcal subfield (PACs)] of the Periamygdaloid Cortex. Thereafter, we focused on projections to the hippocampal formation (dentate gyrus, hippocampus proper, subiculum) and to the parahippocampal region (presubiculum, parasubiculum, entorhinal, and perirhinal and postrhinal cortices). The PACm had the heaviest intradivisional projections and it also originated light interdivisional projections to other Periamygdaloid subfields. Projections from the other subfields converged in the PACs. All subfields provided substantial intra-amygdaloid projections to the medial and posterior cortical nuclei. In addition, the PAC subfield projected to the ventrolateral and medial divisions of the lateral nucleus. The heaviest periamygdalohippocampal projections originated in the PACm and PACs, which projected moderately to the temporal end of the stratum lacunosum moleculare of the CA1 subfield and to the molecular layer of the ventral subiculum. The PACm also projected moderately to the temporal CA3 subfield. The heaviest projections to the entorhinal Cortex originated in the PACs and terminated in the amygdalo-entorhinal, ventral intermediate, and medial subfields. Area 35 of the perirhinal Cortex was lightly innervated by the PAC subfield. Thus, these connections might allow for olfactory information entering the amygdala to become associated with signals from other sensory modalities that enter the amygdala via other nuclei. Further, the periamygdalohippocampal pathways might form one route by which the amygdala modulates memory formation and retrieval in the medial temporal lobe memory system. These pathways can also facilitate the spread of seizure activity from the amygdala to the hippocampal and parahippocampal regions in temporal lobe epilepsy. © 2003 Wiley-Liss, Inc.
Mark H Tuszynski - One of the best experts on this subject based on the ideXlab platform.
-
estrogen receptor beta colocalizes extensively with parvalbumin labeled inhibitory neurons in the Cortex amygdala basal forebrain and hippocampal formation of intact and ovariectomized adult rats
The Journal of Comparative Neurology, 2002Co-Authors: Mathew Blurtonjones, Mark H TuszynskiAbstract:Estrogen has been reported to regulate the activity of γ-aminobutyric acid (GABA)ergic interneurons within the hippocampus, basal forebrain, and hypothalamus of adult rodents. Although estrogen receptor-alpha bearing GABAergic interneurons have been identified previously, the neurotransmitter phenotype of cells that express the more recently characterized estrogen receptor-beta (ER-β) has not been examined in vivo. We, therefore, have used fluorescent immunohistochemistry to further characterize the phenotype of ER-β–bearing cells by double labeling for the GABAergic-associated calcium-binding protein, parvalbumin (PV). We find that a large proportion of ER-β–immunoreactive cells within the Cortex, amygdala, basal forebrain, and hippocampal formation of intact and ovariectomized (ovx) adult rats are PV-immunoreactive. Within the infralimbic, agranular insular, primary motor, parietal association, perirhinal, and lateral entorhinal cortices, an average of 95.6% ± 0.8% (intact) and 94.5% ± 1.4% (ovx) of all ER-β–immunoreactive cells coexpress parvalbumin, and this proportion is strikingly similar across these diverse cortical regions. ER-β/PV double-labeled cells represent 23.3% ± 1.6% (intact) and 25.8% ± 2.0% (ovx) of all PV-labeled cells within these regions. ER-β/PV double-labeled cells are also observed within the lateral, accessory basal, and posterior cortical nuclei of the amygdala, and Periamygdaloid Cortex. Within the basal forebrain, 31.0% ± 3.1% (intact) and 26.0% ± 5.2 % (ovx) of ER-β–immunoreactive cells coexpress PV. Almost all ER-β–immunoreactive cells within the subiculum, a major output region of the hippocampal formation, double label for PV (intact = 97.2% ± 2.8%; ovx = 100% ± 0.0%). Thus, ER-β exhibits extensive colocalization with a subclass of inhibitory neurons, suggesting a potential mechanism whereby estrogen can regulate neuronal excitability in diverse and broad brain regions by modulating inhibitory tone. J. Comp. Neurol. 452:276–287, 2002. © 2002 Wiley-Liss, Inc.
