Anne Westbrook - Academia.edu (original) (raw)

Papers by Anne Westbrook

Research paper thumbnail of Three-dimensional architecture of identified cerebral neurosecretory cells in an insect

Journal of Morphology, 1991

The organization of identified neurosecretory cell groups in the larval brain of the tobacco horn... more The organization of identified neurosecretory cell groups in the larval brain of the tobacco hornworm, Manduca sexta, was investigated immunocytologically. Computer-assisted three-dimensional reconstruction was used to examine the architecture of the neurosecretory cell groups. The group III lateral neurosecretory cells (L-NSC III) which produce the prothoracicotropic hormone are located dorsolaterally in the protocerebrum and extend axons medially that decussate to the contralateral lobe prior to exiting the brain through the nervi corporis cardiaci I + II. The group IIa2 medial neurosecretory cells (M-NSC IIa2) are located anteriorly in the medial dorsal protocerebrum. The axons of these cells also exit the brain via the contralateral nervi corporis cardiaci I + II. However, their axons traverse a different pathway through the brain from that of the L-NSC III axons. Each of the cell groups possesses elaborate dendrites with terminal varicosities. The dendrites can be classified into specific fields based upon their location and projection pattern within the brain. The dendrites for these two neurosecretory cell groups overlap in specific regions of the protocerebral neuropil. After the axons of these neurosecretory cells exit the brain through the retrocerebral nerve, they innervate the corpus allatum where they arborize to form neurohemal terminals in strikingly different patterns. The L-NSC III penetrate throughout the glandular structure and the M-NSC IIa2 terminals are restricted to the external sheath. A third group of cerebral neurosecretory cells, the ventromedial neurons (VM) which stain with the monoclonal antibody to prothoracicotropic hormone in Manduca, are located anteriorly in the medial region of the brain. The axons of these cells do not exit the brain to the retrocerebral complex, but rather pass through the circumesophageal connectives and ventral nerve cord. These neurons appear to be the same VM neurons that produce eclosion hormone. One dendritic field of the L-NSC III terminates in close apposition to the VM neurons. The distinct morphologies of these neurosecretory cell groups in relation to other cell groups and the distribution of neuropeptides within the neurons suggest that insect neurosecretory cells, like their vertebrate counterparts, may have multiple regulatory roles.

Research paper thumbnail of The Biology of the Prothoracicotropic Hormone Peptidergic Neurons in an Insect

Integrative and Comparative Biology, 1993

SYNOPSIS. The prothoracicotropic hormone and the cerebral peptidergic neurons that produce it hav... more SYNOPSIS. The prothoracicotropic hormone and the cerebral peptidergic neurons that produce it have traditionally been thought to have the singular function of acting as a primary effector of insect postembryonic development. Recent investigations of this ...

Research paper thumbnail of Regeneration of the neurohemal terminals for identified cerebral neurosecretory cells in an insect

Journal of Comparative Neurology, 1989

The axons of specific neurosecretory cells, L-NSC III, in the brain of the tobacco hornworm, Mand... more The axons of specific neurosecretory cells, L-NSC III, in the brain of the tobacco hornworm, Manduca sexta, were transected during larval-pupal development to study the effects of this type of lesion on these peptidergic neurons and to begin to identify factors that may regulate their regeneration and growth. The two somata of these bilaterally paired neurons produce the prothoracicotropic hormone and are located in the pars intercerebralis. Their axons exit from the contralateral brain lobe via a retrocerebral nerve and pass through the corpus cardiacum before terminating at the glandular corpus allatum. At the corpus allatum, the L-NSC III axons arborize to form the terminal neurohemal organ for prothoracicotropic hormone release. The retrocerebral nerve was severed either in vitro followed by brain transplantation or in situ; in either protocol, the distal axon segments and corpus allatum were removed. The ability of the injured L-NSC III axons to regenerate was assessed immunocytologically by using a monoclonal antibody against the prothoracicotropic hormone. In both treatments, the proximal axon stumps exhibited regenerative growth as early as 1 day after axotomy, and, by the third day, neurites had extended. By the fifth day, the regenerating axons had branched to form terminal varicosities similar to those of a normal neurohemal organ. The regenerated neurohemal structure appeared to be functional, because larvae that had been bilaterally axotomized were able to metamorphose to pupae, a process requiring temporally precise periods of prothoracicotropic hormone release. In addition to the regeneration of the terminal axon structures, several other responses to axotomy and retrocerebral organ excision occurred. These included an apparent accumulation of prothoracicotropic hormone in the axons and regenerating neurohemal-like structures, sprouting of ectopic neurites from the axotomized somata, and a change in shape of the cell bodies from spherical to ovoid.

Research paper thumbnail of Changing Middle Schoolers' Attitudes About Mental Illness Through Education

Schizophrenia Bulletin, 2004

The field test of The Science of Mental Illness curriculum supplement for middle school (grades 6... more The field test of The Science of Mental Illness curriculum supplement for middle school (grades 6-8) children provided an opportunity to assess knowledge and attitudes about mental illness in more than 1,500 middle school students throughout the United States and to evaluate the impact of an educational intervention on stigma-related attitudes. Two primary questions were examined: (1) what are the baseline knowledge and attitudes about mental illness in this sample of middle school students, and (2) does participation in a curriculum about the science of mental illness increase knowledge and improve attitudes about mental illness? Consistent with findings from other studies, results indicate that students had some understanding of mental illness as a problem of the brain with biological and psychosocial causes; however, they lacked knowledge about treatment and overall were "not sure" about many aspects of mental illness. The students did not strongly endorse negative attitudes about mental illness at baseline. The curriculum produced significant improvements in both knowledge and attitudes at posttest and was most effective in improving attitudes among those with more negative baseline attitudes. These findings suggest that a brief educational program can be an effective intervention to increase knowledge and improve attitudes about mental illness.

Research paper thumbnail of How Do Children Stigmatize People With Mental Illness

Journal of Applied Social Psychology, 2007

A way to promote eliminating stigma surrounding mental illnesses is targeting the phenomenon in c... more A way to promote eliminating stigma surrounding mental illnesses is targeting the phenomenon in children. This study's purpose is to validate models of mental illness stigma on children in Grades 6–8. Children completed the revised Attribution Questionnaire in a pretest of a larger study on a mental health education program. Data from this study permitted testing of roles of demographics in these social cognitive models. Subsequent analyses using manifest model structural equations were mixed, but mostly showed adequate fit for multiple versions of the models. These results suggest that models of blame and dangerousness are relevant to the way 10 to 13-year-olds stigmatize mental illness. Demographics were not found to fit these models satisfactorily. Implications of these findings for stigma-change agenda are discussed.

Research paper thumbnail of Developmental expression of the prothoracicotropic hormone in the CNS of the Tobacco HornwormManduca sexta

Journal of Comparative Neurology, 1993

The prothoracicotropic hormone is an insect neuropeptide released into the hemolymph to signal mo... more The prothoracicotropic hormone is an insect neuropeptide released into the hemolymph to signal molting and metamorphosis through its stimulation of steroidogenesis. The only known source of the prothoracicotropic hormone in the tobacco hornworm, Manduca sexta, has been a group of lateral cerebral neurosecretory cells, the L-NSC III. In this study, the developmental and spatial distribution of the prothoracicotropic hormone was examined throughout the life cycle of Manduca. In common with many vertebrates and invertebrates in which neuropeptides are located in several regions within the central nervous system (CNS), the prothoracicotropic hormone phenotype in Manduca is expressed by CNS neurons in addition to the L-NSC III. These neurons are located in the brain, frontal ganglion, and subesophageal ganglion. One cerebral neurosecretory cell group, the ventromedial neurons, expresses the prothoracicotropic hormone phenotype and the behavioral neurohormone, eclosion hormone. Whereas the L-NSC III and the ventromedial neurons express the peptide phenotype throughout the life cycle, the other neurons express the peptide only during the embryonic and larval stages. This precise spatial and temporal expression of the prothoracicotropic hormone by different groups of neurosecretory cells raises the possibility that in Manduca the peptide may, in addition to its known neuroendocrine function, play other physiological roles in different ways at different stages of the life cycle. © 1993 Wiley-Liss, Inc.

Research paper thumbnail of Three-dimensional architecture of identified cerebral neurosecretory cells in an insect

Journal of Morphology, 1991

The organization of identified neurosecretory cell groups in the larval brain of the tobacco horn... more The organization of identified neurosecretory cell groups in the larval brain of the tobacco hornworm, Manduca sexta, was investigated immunocytologically. Computer-assisted three-dimensional reconstruction was used to examine the architecture of the neurosecretory cell groups. The group III lateral neurosecretory cells (L-NSC III) which produce the prothoracicotropic hormone are located dorsolaterally in the protocerebrum and extend axons medially that decussate to the contralateral lobe prior to exiting the brain through the nervi corporis cardiaci I + II. The group IIa2 medial neurosecretory cells (M-NSC IIa2) are located anteriorly in the medial dorsal protocerebrum. The axons of these cells also exit the brain via the contralateral nervi corporis cardiaci I + II. However, their axons traverse a different pathway through the brain from that of the L-NSC III axons. Each of the cell groups possesses elaborate dendrites with terminal varicosities. The dendrites can be classified into specific fields based upon their location and projection pattern within the brain. The dendrites for these two neurosecretory cell groups overlap in specific regions of the protocerebral neuropil. After the axons of these neurosecretory cells exit the brain through the retrocerebral nerve, they innervate the corpus allatum where they arborize to form neurohemal terminals in strikingly different patterns. The L-NSC III penetrate throughout the glandular structure and the M-NSC IIa2 terminals are restricted to the external sheath. A third group of cerebral neurosecretory cells, the ventromedial neurons (VM) which stain with the monoclonal antibody to prothoracicotropic hormone in Manduca, are located anteriorly in the medial region of the brain. The axons of these cells do not exit the brain to the retrocerebral complex, but rather pass through the circumesophageal connectives and ventral nerve cord. These neurons appear to be the same VM neurons that produce eclosion hormone. One dendritic field of the L-NSC III terminates in close apposition to the VM neurons. The distinct morphologies of these neurosecretory cell groups in relation to other cell groups and the distribution of neuropeptides within the neurons suggest that insect neurosecretory cells, like their vertebrate counterparts, may have multiple regulatory roles.

Research paper thumbnail of The Biology of the Prothoracicotropic Hormone Peptidergic Neurons in an Insect

Integrative and Comparative Biology, 1993

SYNOPSIS. The prothoracicotropic hormone and the cerebral peptidergic neurons that produce it hav... more SYNOPSIS. The prothoracicotropic hormone and the cerebral peptidergic neurons that produce it have traditionally been thought to have the singular function of acting as a primary effector of insect postembryonic development. Recent investigations of this ...

Research paper thumbnail of Regeneration of the neurohemal terminals for identified cerebral neurosecretory cells in an insect

Journal of Comparative Neurology, 1989

The axons of specific neurosecretory cells, L-NSC III, in the brain of the tobacco hornworm, Mand... more The axons of specific neurosecretory cells, L-NSC III, in the brain of the tobacco hornworm, Manduca sexta, were transected during larval-pupal development to study the effects of this type of lesion on these peptidergic neurons and to begin to identify factors that may regulate their regeneration and growth. The two somata of these bilaterally paired neurons produce the prothoracicotropic hormone and are located in the pars intercerebralis. Their axons exit from the contralateral brain lobe via a retrocerebral nerve and pass through the corpus cardiacum before terminating at the glandular corpus allatum. At the corpus allatum, the L-NSC III axons arborize to form the terminal neurohemal organ for prothoracicotropic hormone release. The retrocerebral nerve was severed either in vitro followed by brain transplantation or in situ; in either protocol, the distal axon segments and corpus allatum were removed. The ability of the injured L-NSC III axons to regenerate was assessed immunocytologically by using a monoclonal antibody against the prothoracicotropic hormone. In both treatments, the proximal axon stumps exhibited regenerative growth as early as 1 day after axotomy, and, by the third day, neurites had extended. By the fifth day, the regenerating axons had branched to form terminal varicosities similar to those of a normal neurohemal organ. The regenerated neurohemal structure appeared to be functional, because larvae that had been bilaterally axotomized were able to metamorphose to pupae, a process requiring temporally precise periods of prothoracicotropic hormone release. In addition to the regeneration of the terminal axon structures, several other responses to axotomy and retrocerebral organ excision occurred. These included an apparent accumulation of prothoracicotropic hormone in the axons and regenerating neurohemal-like structures, sprouting of ectopic neurites from the axotomized somata, and a change in shape of the cell bodies from spherical to ovoid.

Research paper thumbnail of Changing Middle Schoolers' Attitudes About Mental Illness Through Education

Schizophrenia Bulletin, 2004

The field test of The Science of Mental Illness curriculum supplement for middle school (grades 6... more The field test of The Science of Mental Illness curriculum supplement for middle school (grades 6-8) children provided an opportunity to assess knowledge and attitudes about mental illness in more than 1,500 middle school students throughout the United States and to evaluate the impact of an educational intervention on stigma-related attitudes. Two primary questions were examined: (1) what are the baseline knowledge and attitudes about mental illness in this sample of middle school students, and (2) does participation in a curriculum about the science of mental illness increase knowledge and improve attitudes about mental illness? Consistent with findings from other studies, results indicate that students had some understanding of mental illness as a problem of the brain with biological and psychosocial causes; however, they lacked knowledge about treatment and overall were "not sure" about many aspects of mental illness. The students did not strongly endorse negative attitudes about mental illness at baseline. The curriculum produced significant improvements in both knowledge and attitudes at posttest and was most effective in improving attitudes among those with more negative baseline attitudes. These findings suggest that a brief educational program can be an effective intervention to increase knowledge and improve attitudes about mental illness.

Research paper thumbnail of How Do Children Stigmatize People With Mental Illness

Journal of Applied Social Psychology, 2007

A way to promote eliminating stigma surrounding mental illnesses is targeting the phenomenon in c... more A way to promote eliminating stigma surrounding mental illnesses is targeting the phenomenon in children. This study's purpose is to validate models of mental illness stigma on children in Grades 6–8. Children completed the revised Attribution Questionnaire in a pretest of a larger study on a mental health education program. Data from this study permitted testing of roles of demographics in these social cognitive models. Subsequent analyses using manifest model structural equations were mixed, but mostly showed adequate fit for multiple versions of the models. These results suggest that models of blame and dangerousness are relevant to the way 10 to 13-year-olds stigmatize mental illness. Demographics were not found to fit these models satisfactorily. Implications of these findings for stigma-change agenda are discussed.

Research paper thumbnail of Developmental expression of the prothoracicotropic hormone in the CNS of the Tobacco HornwormManduca sexta

Journal of Comparative Neurology, 1993

The prothoracicotropic hormone is an insect neuropeptide released into the hemolymph to signal mo... more The prothoracicotropic hormone is an insect neuropeptide released into the hemolymph to signal molting and metamorphosis through its stimulation of steroidogenesis. The only known source of the prothoracicotropic hormone in the tobacco hornworm, Manduca sexta, has been a group of lateral cerebral neurosecretory cells, the L-NSC III. In this study, the developmental and spatial distribution of the prothoracicotropic hormone was examined throughout the life cycle of Manduca. In common with many vertebrates and invertebrates in which neuropeptides are located in several regions within the central nervous system (CNS), the prothoracicotropic hormone phenotype in Manduca is expressed by CNS neurons in addition to the L-NSC III. These neurons are located in the brain, frontal ganglion, and subesophageal ganglion. One cerebral neurosecretory cell group, the ventromedial neurons, expresses the prothoracicotropic hormone phenotype and the behavioral neurohormone, eclosion hormone. Whereas the L-NSC III and the ventromedial neurons express the peptide phenotype throughout the life cycle, the other neurons express the peptide only during the embryonic and larval stages. This precise spatial and temporal expression of the prothoracicotropic hormone by different groups of neurosecretory cells raises the possibility that in Manduca the peptide may, in addition to its known neuroendocrine function, play other physiological roles in different ways at different stages of the life cycle. © 1993 Wiley-Liss, Inc.