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Peter C. Holland - One of the best experts on this subject based on the ideXlab platform.
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disconnection of the amygdala central nucleus and the Substantia innominata nucleus basalis magnocellularis disrupts performance in a sustained attention task
Behavioral Neuroscience, 2007Co-Authors: Peter C. HollandAbstract:The basal forebrain cholinergic system is broadly implicated in the regulation of attention. Disruptions in the function of this system produce impairments in many attentional functions, including the performance of well-learned responses under increased attentional load and the surprise-induced enhancement of learning rate. Similarly, lesions of the amygdala central nucleus (CeA) have been found to impair attentional function in some circumstances. In the present article, the effects of lesions that disconnected CeA from the cholinergic Substantia innominata/nucleus basalis magnocellularis (SI/nBM) on performance are examined in a modified 5-choice serial reaction time (5CSRT) task, thought to assess selective or sustained attention. The lesions impaired performance under conditions of increased attentional load, suggesting that a circuit that includes CeA and SI/nBM regulates these aspects of attention.
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Disconnection of the amygdala central nucleus and the Substantia innominata/nucleus basalis magnocellularis disrupts performance in a sustained attention task.
Behavioral neuroscience, 2007Co-Authors: Peter C. HollandAbstract:The basal forebrain cholinergic system is broadly implicated in the regulation of attention. Disruptions in the function of this system produce impairments in many attentional functions, including the performance of well-learned responses under increased attentional load and the surprise-induced enhancement of learning rate. Similarly, lesions of the amygdala central nucleus (CeA) have been found to impair attentional function in some circumstances. In the present article, the effects of lesions that disconnected CeA from the cholinergic Substantia innominata/nucleus basalis magnocellularis (SI/nBM) on performance are examined in a modified 5-choice serial reaction time (5CSRT) task, thought to assess selective or sustained attention. The lesions impaired performance under conditions of increased attentional load, suggesting that a circuit that includes CeA and SI/nBM regulates these aspects of attention.
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disconnection of the amygdala central nucleus and Substantia innominata nucleus basalis disrupts increments in conditioned stimulus processing in rats
Behavioral Neuroscience, 1999Co-Authors: Jung Soo Han, Peter C. Holland, Michela GallagherAbstract:Rats with a neurotoxic lesion of the amygdala central nucleus (CN) in one hemisphere and a 192 immunoglobulin G (192IgG)-saporin lesion of cholinergic neurons in the contralateral Substantia innominata/nucleus basalis (SI/nBM) failed to show the enhanced attentional processing of a conditioned stimulus (CS) observed in sham-operated rats when that CS's predictive value was altered. Performance of these asymmetrically lesioned rats was poorer than that of rats with a unilateral lesion of either structure or with a symmetrical lesion of both structures in the same hemisphere. These results implicate connections between the CN and SI/nBM in the incremental attentional processing of CSs, extending previous research that has shown similar effects of bilateral lesions of either the CN or the SI/nBM.
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Disconnection of the amygdala central nucleus and Substantia innominata/nucleus basalis disrupts increments in conditioned stimulus processing in rats.
Behavioral neuroscience, 1999Co-Authors: Jung Soo Han, Peter C. Holland, Michela GallagherAbstract:Rats with a neurotoxic lesion of the amygdala central nucleus (CN) in one hemisphere and a 192 immunoglobulin G (192IgG)-saporin lesion of cholinergic neurons in the contralateral Substantia innominata/nucleus basalis (SI/nBM) failed to show the enhanced attentional processing of a conditioned stimulus (CS) observed in sham-operated rats when that CS's predictive value was altered. Performance of these asymmetrically lesioned rats was poorer than that of rats with a unilateral lesion of either structure or with a symmetrical lesion of both structures in the same hemisphere. These results implicate connections between the CN and SI/nBM in the incremental attentional processing of CSs, extending previous research that has shown similar effects of bilateral lesions of either the CN or the SI/nBM.
François Dauphin - One of the best experts on this subject based on the ideXlab platform.
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Autoradiographic mapping of cerebral blood flow responses to cholinergic stimulation of the rat Substantia innominata: modulatory effect of galanin
Brain research, 1998Co-Authors: Alexandra Barbelivien, Eric T. Mackenzie, François DauphinAbstract:In order to analyze the precise cerebrovascular effects of a specific cholinergic stimulation of the rat Substantia innominata and their modulation by galanin, cerebral blood flow was measured by the [14C]-iodoantipyrine autoradiographic method in anesthetized (urethane and α-chloralose), artificially ventilated male Sprague–Dawley rats that received a microinjection into the Substantia innominata of saline (n=7), or 63 pmol of galanin (n=8), or 50 nmoles of carbachol (n=6) or a coinjection of carbachol and galanin (n=8). Significant carbachol-induced cerebral blood flow increases were noted in ipsilateral cortices (+36%, p
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autoradiographic mapping of cerebral blood flow responses to cholinergic stimulation of the rat Substantia innominata modulatory effect of galanin
Brain Research, 1998Co-Authors: Alexandra Barbelivien, Eric T. Mackenzie, François DauphinAbstract:In order to analyze the precise cerebrovascular effects of a specific cholinergic stimulation of the rat Substantia innominata and their modulation by galanin, cerebral blood flow was measured by the [14C]-iodoantipyrine autoradiographic method in anesthetized (urethane and α-chloralose), artificially ventilated male Sprague–Dawley rats that received a microinjection into the Substantia innominata of saline (n=7), or 63 pmol of galanin (n=8), or 50 nmoles of carbachol (n=6) or a coinjection of carbachol and galanin (n=8). Significant carbachol-induced cerebral blood flow increases were noted in ipsilateral cortices (+36%, p<0.01 in the cingulate to +82%, p<0.01 in the parietal somatosensory cortices), but also in ipsilateral hippocampus and ipsilateral thalamus. These cerebral blood flow increases were abolished by the coinjection of carbachol and galanin, while infusions of galanin alone failed to affect cerebral blood flow. Cholinergic stimulation of the Substantia innominata represents thus a good model for the analysis of the detailed pharmacological properties of the cholinergic vasodilatatory basalocortical system. The existence of an inhibitory galaninergic modulation of this system could be of particular interest, in terms of cerebrovascular reactivity, in various neurodegenerative states.
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Regional cerebral blood flow responses to neurochemical stimulation of the Substantia innominata in the anaesthetized rat
Neuroscience letters, 1995Co-Authors: Alexandra Barbeliview, Eric T. Mackenzie, François DauphinAbstract:Since electrical stimulation of neurones may activate not only cell bodies but also neuronal fibres, this study aimed to test a selectively cholinergic neurochemical stimulation of the rat Substantia innominata (SI) by the local microinjection of carbachol; the effects of this acetylcholine agonist were compared with glutamate. Cortical and subcortical cerebral blood flow (CBF) were measured in anaesthetized rats with the [14C]iodoantipyrine method by the tissue sampling technique immediately following the intracerebral (SI) microinjection of saline, 50 nmol of carbachol or glutamate. Carbachol microinjection into the SI induced a transient but significant vasodilation in frontoparietal motor (+28%) and temporal (+41%) cortices, that lasted for less than 10 min. Glutamate did not elicit any significant CBF modifications when compared to control rats although a significant interhemispheric asymmetry after microinjection was observed in the frontoparietal motor cortex. This latter observation would suggest that the glutamate-induced cortical response is less pronounced than that elicited by carbachol. Overall, these results demonstrate that a selective cholinergic stimulation of the SI can induce a transient cortical vasodilation and further confirms the hypothesis of a muscarinic modulation of CBF via this basal structure.
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Autoradiographic study of the cerebrovascular effects of stimulation of the Substantia innominata: convenient stimulation paradigm
Journal of the Autonomic Nervous System, 1994Co-Authors: Elvire Vaucher, François Dauphin, Jacques Seylaz, Pierre LacombeAbstract:The aim of this study was to determine the distribution within the whole brain of the vascular effects of stimulation of the Substantia innominata. This basal forebrain nucleus is the major cholinergic input in the neocortex in the rodent. The local cerebral blood flow was measured by the autoradiographic [14C]iodoantipyrine technique in a group of control and a group of stimulated unanesthetized rats. The Substantia innominata was electrically stimulated through a chronically implanted electrode. The stimulation induced blood flow increases exceeding 200% in the hemisphere ipsilateral to the stimulation and 100% in the contralateral hemisphere compared to the control group. The ipsilateral vasodilations were observed not only in the cortical areas but also in some subcortical structures. Comparison with previous data suggests that part of the effects is due to cholinergic neurons of the Substantia innominata and part to non-cholinergic neurons and indirect effects. However, only two out of eight stimulated rats displayed this response. The low reproducibility of the results is discussed, considering the stimulation paradigm which has been developed for future measurements of the cerebral glucose utilization which requires a long duration stimulation period.
Alexander R. Cools - One of the best experts on this subject based on the ideXlab platform.
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Motor activity and the GABAA-receptor in the ventral pallidum/Substantia innominata complex
Neuroscience letters, 1991Co-Authors: Ruud Van Den Bos, Alexander R. CoolsAbstract:The present study deals with the role of the γ-aminobutyric acid-A (GABAA) receptor in motor activity in the rostral part of the ventral pallidum/Substantia innominata complex. Both the specific GABAA antagonist bicuculline () and the GABAA agonist muscimol () enhanced motor activity. It was moreover found that bicuculline (50–100 ng) dose-dependently attenuated the activity induced by muscimol (25 ng). Conversely, muscimol (25 ng) attenuated the biculline (25–50 ng) induced activity. These data thus show that both stimulation and blockade of GABAA receptors within the area under study enhance motor activity.
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motor activity and the gabaa receptor in the ventral pallidum Substantia innominata complex
Neuroscience Letters, 1991Co-Authors: Ruud Van Den Bos, Alexander R. CoolsAbstract:The present study deals with the role of the γ-aminobutyric acid-A (GABAA) receptor in motor activity in the rostral part of the ventral pallidum/Substantia innominata complex. Both the specific GABAA antagonist bicuculline () and the GABAA agonist muscimol () enhanced motor activity. It was moreover found that bicuculline (50–100 ng) dose-dependently attenuated the activity induced by muscimol (25 ng). Conversely, muscimol (25 ng) attenuated the biculline (25–50 ng) induced activity. These data thus show that both stimulation and blockade of GABAA receptors within the area under study enhance motor activity.
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Efferent connections of the striatopallidal and amygdaloid components of the Substantia innominata in the cat: projections to the nucleus accumbens and caudate nucleus.
Neuroscience, 1991Co-Authors: Will P. J. M. Spooren, Jan G. Veening, H.j. Groenewegen, Alexander R. CoolsAbstract:Abstract Enkephalin immunoreactivity is used to divide the feline Substantia innominata into circumscript subregions, i.e. the “striatopallidal system” and the “extended amygdala”. In addition, enkephalin immunoreactivity is used to subdivide the striatopallidal system into two distinct areas, i.e. the subcommissural part of the globus pallidus displaying high enkephalin immunoreactivity and the ventral pallidum displaying moderate enkephalin immunoreactivity. The anterograde axonal transport of Phaseolus vulgaris -leucoagglutinin is used to study the efferents of these areas innervating the caudate nucleus and the nucleus accumbens. It is found that the enkephalin-immunoreactive subcommissural part of the globus pallidus as well as the dorsal enkephalin-immunoreactive regions of the extended amygdala project topographically along a rostrocaudal and mediolateral dimension to the nucleus accumbens. The far rostral parts of the caudate nucleus are found to be innervated by the subcommissural part of the globus pallidus whereas the extended amygdala has no such connection. This pathway is also found to be topographically organized along a mediolateral dimension. The non-enkephalin-immunoreactive area ventral and lateral to the subcommissural part of the globus pallidus is found to have no projections to the nucleus accumbens and caudate nucleus. This region rather innervates the olfactory tubercle. In contrast to the striatopallidal system the sublenticular part of the extended amygdala preferentially projects to the adjoining part of the extended amygdala, i.e. the bed nucleus of the stria terminalis. However, the ventral regions preferentially innervate the medial division of the bed nucleus of the stria terminalis whereas the dorsal regions preferentially innervate the lateral division of the bed nucleus of the stria terminalis. These data indicate that the differential forebrain systems represented in the feline Substantia innominata, i.e. the striatopallidal system and extended amygdala have differential output stations. The results are discussed in view of the role of the subcommissural part of the globus pallidus and the nucleus aecumbens in orofacial dyskinesia and schizophrenia, respectively.
Kimihiko Abe - One of the best experts on this subject based on the ideXlab platform.
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MR analysis of the Substantia innominata in normal aging, Alzheimer disease, and other types of dementia
2015Co-Authors: Haruo Hanyu, Tetsuichi Asano, Hirofumi Sakurai, Yuriko Tanaka, Masaru Takasaki, Kimihiko AbeAbstract:BACKGROUND AND PURPOSE: The Substantia innominata can be visualized on coronal thin-section T2-weighted MR images. The purpose of this study was to investigate the morpho-logic changes of the Substantia innominata in normal aging by using MR imaging and to determine whether the changes in this structure on MR images were specific to Alzheimer disease (AD). METHODS: The thickness of the Substantia innominata was measured on the coronal T2-weighted image obtained through the anterior commissure in 39 healthy control subjects (age range, 25–86 y; mean age, 62 y); 39 patients with AD; and 36 patients with non-AD dementia, including vascular dementia, frontotemporal dementia, and Parkinson disease with dementia. RESULTS: In the control subjects, the thickness of the Substantia innominata significantly decreased with age. Compared with age-matched control subjects, both patients with AD and patients with non-AD dementia had significant atrophy of the Substantia innominata. The thickness of the Substantia innominata significantly correlated with scores from the Mini-Mental State Examination in patients with AD but not in patients with non-AD dementia
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MR features of the Substantia innominata and therapeutic implications in dementias
Neurobiology of aging, 2006Co-Authors: Haruo Hanyu, Yuriko Tanaka, Soichiro Shimizu, Kentaro Hirao, Toshihiko Iwamoto, Kimihiko AbeAbstract:Abstract We measured the thickness of the Substantia innominata using magnetic resonance imaging in 122 patients with Alzheimer's disease (AD), 31 patients with dementia with Lewy bodies (DLB) and 34 patients with vascular dementia (VaD), and examined the correlates of cognitive response to donepezil. Although all dementia groups showed significant atrophy of the Substantia innominata compared to 28 age-matched controls, atrophy was greater in the DLB group, but less in the VaD group than the AD group. Mini-Mental State Examination score changes at 12 weeks after donepezil administration inversely and significantly correlated with the thickness of the Substantia innominata in patients with AD ( n = 103, r = −0.43, p n = 24, r = −0.57, p n = 12, r = −0.22, p > 0.1). There may be some differences in cholinergic impairment among AD, DLB and VaD, reflecting cholinergic neuropathology. Clinical response to cholinergic therapy may be partly attributable to damaged cholinergic neurons in AD and DLB, but not in VaD, suggesting differences in the therapeutic implication of cholinergic system degeneration.
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Atrophy of the Substantia innominata on magnetic resonance imaging predicts response to donepezil treatment in Alzheimer's disease patients.
Dementia and geriatric cognitive disorders, 2003Co-Authors: Yuriko Tanaka, Haruo Hanyu, Hirofumi Sakurai, Masaru Takasaki, Kimihiko AbeAbstract:To investigate whether atrophy of the Substantia innominata as shown on magnetic resonance imaging (MRI), reflecting degeneration of cholinergic neurons in the nucleus basalis of Meynert, predicts response to donepezil treatment in patients with Alzheimer's disease (AD), we studied correlations between the thickness of the Substantia innominata and clinical efficacy. Eighty-two patients were divided into responders, including transiently and continuously responding groups, and nonresponders, based on the changes in the Mini-Mental State Examination (MMSE) score from baseline at 3 months and at 12 months. Atrophy of the Substantia innominata was more pronounced in transiently and continuously responding groups than nonresponders, but no significant change in the thickness between transiently and continuously responding groups was found. The MMSE score changes from baseline at 3 months and at 12 months significantly inversely correlated with the thickness of the Substantia innominata. Logistic regression analysis revealed that the overall discrimination rate with the thickness of the Substantia innominata was 70% between responders and nonresponders. We conclude that atrophy of the Substantia innominata on MRI helps to predict response to donepezil treatment in patients with AD.
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Atrophy of the Substantia innominata on magnetic resonance imaging and response to donepezil treatment in Alzheimer's disease
Neuroscience letters, 2002Co-Authors: Haruo Hanyu, Hirofumi Sakurai, Yuriko Tanaka, Masaru Takasaki, Kimihiko AbeAbstract:Atrophy of the Substantia innominata on magnetic resonance imaging (MRI), reflecting degeneration of cholinergic neurons in the nucleus basalis of Meynert, may be an in vivo marker of cholinergic damage. We attempted to investigate whether the MRI features of the Substantia innominata predict response to donepezil treatment in Alzheimer's patients. The thickness of the Substantia innominata was measured on the coronal T2-weighted MRI through the anterior commissure. Seventy-two patients treated with donepezil were divided into the two groups (responders and non-responders) based on changes in Mini-Mental State Examination (MMSE) scores from baseline to study endpoint. Atrophy of the Substantia innominata was more pronounced in responders than non-responders. There was a significant inverse correlation between thickness of the Substantia innominata and MMSE changes. MRI analysis of the Substantia innominata may be a simple and practical method for the selection of possible treatment responders.
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MR Analysis of the Substantia innominata in Normal Aging, Alzheimer Disease, and Other Types of Dementia
AJNR. American journal of neuroradiology, 2002Co-Authors: Haruo Hanyu, Tetsuichi Asano, Hirofumi Sakurai, Yuriko Tanaka, Masaru Takasaki, Kimihiko AbeAbstract:BACKGROUND AND PURPOSE: The Substantia innominata can be visualized on coronal thin-section T2-weighted MR images. The purpose of this study was to investigate the morphologic changes of the Substantia innominata in normal aging by using MR imaging and to determine whether the changes in this structure on MR images were specific to Alzheimer disease (AD). METHODS: The thickness of the Substantia innominata was measured on the coronal T2-weighted image obtained through the anterior commissure in 39 healthy control subjects (age range, 25–86 y; mean age, 62 y); 39 patients with AD; and 36 patients with non-AD dementia, including vascular dementia, frontotemporal dementia, and Parkinson disease with dementia. RESULTS: In the control subjects, the thickness of the Substantia innominata significantly decreased with age. Compared with age-matched control subjects, both patients with AD and patients with non-AD dementia had significant atrophy of the Substantia innominata. The thickness of the Substantia innominata significantly correlated with scores from the Mini-Mental State Examination in patients with AD but not in patients with non-AD dementia. CONCLUSION: MR analysis reveals age-related shrinkage of the Substantia innominata. Atrophy of the Substantia innominata, which reflects degeneration in the nucleus basalis of Meynert, is pronounced both in patients with AD and in those with non-AD dementia. MR imaging features in this structure may not be specific to AD.
Kyriaki Thermos - One of the best experts on this subject based on the ideXlab platform.
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Somatostatin receptors in the ventral pallidum/Substantia innominata modulate rat locomotor activity.
Psychopharmacology, 2005Co-Authors: A. Marazioti, Andreas Kastellakis, Katerina Antoniou, D. Papasava, Kyriaki ThermosAbstract:Rational Somatostatin and its receptors (sst1 and sst2) have been localized in brain nuclei implicated in motor control, such as the nucleus accumbens, ventral pallidum (VP) and Substantia innominata (SI).
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somatostatin receptors in the ventral pallidum Substantia innominata modulate rat locomotor activity
Psychopharmacology, 2005Co-Authors: A. Marazioti, Andreas Kastellakis, Katerina Antoniou, D. Papasava, Kyriaki ThermosAbstract:Rational Somatostatin and its receptors (sst1 and sst2) have been localized in brain nuclei implicated in motor control, such as the nucleus accumbens, ventral pallidum (VP) and Substantia innominata (SI).
