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Cyborg: ‘cybernetic + organism’?!!
634
News & Comment
neurons is required to synchronize rhythmic electrical activity in these spinal networks. Pharmacological blockade of glutamatergic synaptic transmission did not affect the spontaneous generation of periodic membrane depolarizations in some of these coupled neurons. Indeed, complete blockade of chemical transmission (by injection of botulinum neurotoxin type B) paralyzed embryos but spared these periodic depolarizations. In contrast, blockers of gap junctions, such as heptanol and cytoplasmic acidification, abolished the periodic depolarizations. More importantly, the periodic depolarizations of some of these pairs of electrotonically coupled
TRENDS in Neurosciences Vol.24 No.11 November 2001
neurons were correlated with coactivity in the connected cells, indicating that these depolarizations result from synchronized network activity among these neurons. Further studies by the authors showed that gap-junctional generation of periodic depolarizations involves activation of calcium-dependent potassium channels. These findings reveal the importance of electrotonic coupling in the generation of rhythmic neuronal network activity in an early embryo. They describe, perhaps, the earliest developmental time at which synchronized neural activity has been recorded in identified spinal neurons of a living vertebrate embryo. It will be
interesting to record the activities of coupled spinal neurons in mutant zebrafish embryos with defects in rhythmic movements. Such studies might identify the genes and proteins that are important for the in vivo regulation of electrotonic coupling and synapse formation during early neural development.
these efforts, the HHMI hopes to improve the quality of undergraduate science classes for both majors and non-majors, as well as create a community of scientisteducators who will lead larger-scale curriculum improvements. LO
Max-Planck Institute in Munich shows that individual neurons from the snail Lymnaea stagnalis, immobilized onto a microelectronic substrate establish a signaling circuit connected by strong electric synapses propagating action potentials, which can be measured and controlled electronically. With further technological refining, the neuroelectronic model described in this study will probably simplify the study of synaptic modulation in neuronal networks and help unravel the underlying mechanisms of memory. Proc. Natl. Acad. Sci. U. S. A. 98, 10457–10462. SS
1 Saint-Amant, L. and Drapeau, P. (2001) Synchronization of an embryonic network of identified spinal interneurons solely by electrical coupling. Neuron 31, 1035–1046
Peter V. Nguyen [email protected]
In Brief
Caged animal concerns Laboratory rodents housed in standard, empty cages exhibit stereotypic behaviors that could indicate brain abnormalities, reported Joseph Garner of the University of California, Davis, at the International Society for Applied Ethology Congress. The stereotypies – pacing, incessant grooming, repetitive cage biting and scratching – are most prevalent in these nocturnal animals at night, and are often underappreciated by researchers who work with animals during the day. As stereotypies in humans are associated with basal ganglia damage, and mice raised in enriched environments have been shown to have more neurons and better memory, these findings have implications for many studies in the neurosciences. LO
Teaching worth a million The Howard Hughes Medical Institute (HHMI) has announced new grants to promote innovative undergraduate science education strategies and to support university research scientists who also make teaching a priority. Eighty-four research universities have been invited to nominate tenured faculty members to compete for one of the 20 US$1 million grants that will be awarded to proposals that infuse education programs with more of the excitement, enthusiasm, creativity and spirit of research strategies. Through http://tins.trends.com
Wellcome Trust sets new standards of conduct Next year, research institutions receiving funding from the Wellcome Trust will have to adhere to new guidelines for good science practice and new procedures for handling cases of misconduct, plagiarism and falsification. Among the changes: the trust might carry out misconduct investigations independently from the investigations carried out by research institutions. The Wellcome Trust guidelines are more extensive than the existing governmental research council guidelines, but as the trust funds nearly 20% of biomedical research in the United Kingdom, the majority of universities will probably adopt the Wellcome Trust stipulations and effectively make them the new British standard. LO
Cyborg: ‘cybernetic + organism’ ?!! Well, no, not yet. However, the successful development of a noninvasive neuroelectronic interface system consisting of an elementary circuit of two neurons synaptically connected to a semiconductor chip presages the advent of an era of neurocomputation and neuroengineering. The study by Zeck and Fromherz at the
A complex role for genetics in autism Autism results from a complex interaction between several different genes involved in brain signaling and development. In a large-scale collaboration between the United States and Europe, researchers have now found that two regions on chromosomes 2 and 7 are strongly linked to autism, and that chromosomes 16 and 17 also contain genes involved in autism although a weaker correlation was observed. Excitement arose from the fact that chromosome 7 is known to be associated with several language disorders. The investigators have announced that trials will now be performed to determine how environmental factors influence these genes to produce the wide range of symptoms that
0166-2236/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.
News & Comment
neurons is required to synchronize rhythmic electrical activity in these spinal networks. Pharmacological blockade of glutamatergic synaptic transmission did not affect the spontaneous generation of periodic membrane depolarizations in some of these coupled neurons. Indeed, complete blockade of chemical transmission (by injection of botulinum neurotoxin type B) paralyzed embryos but spared these periodic depolarizations. In contrast, blockers of gap junctions, such as heptanol and cytoplasmic acidification, abolished the periodic depolarizations. More importantly, the periodic depolarizations of some of these pairs of electrotonically coupled
TRENDS in Neurosciences Vol.24 No.11 November 2001
neurons were correlated with coactivity in the connected cells, indicating that these depolarizations result from synchronized network activity among these neurons. Further studies by the authors showed that gap-junctional generation of periodic depolarizations involves activation of calcium-dependent potassium channels. These findings reveal the importance of electrotonic coupling in the generation of rhythmic neuronal network activity in an early embryo. They describe, perhaps, the earliest developmental time at which synchronized neural activity has been recorded in identified spinal neurons of a living vertebrate embryo. It will be
interesting to record the activities of coupled spinal neurons in mutant zebrafish embryos with defects in rhythmic movements. Such studies might identify the genes and proteins that are important for the in vivo regulation of electrotonic coupling and synapse formation during early neural development.
these efforts, the HHMI hopes to improve the quality of undergraduate science classes for both majors and non-majors, as well as create a community of scientisteducators who will lead larger-scale curriculum improvements. LO
Max-Planck Institute in Munich shows that individual neurons from the snail Lymnaea stagnalis, immobilized onto a microelectronic substrate establish a signaling circuit connected by strong electric synapses propagating action potentials, which can be measured and controlled electronically. With further technological refining, the neuroelectronic model described in this study will probably simplify the study of synaptic modulation in neuronal networks and help unravel the underlying mechanisms of memory. Proc. Natl. Acad. Sci. U. S. A. 98, 10457–10462. SS
1 Saint-Amant, L. and Drapeau, P. (2001) Synchronization of an embryonic network of identified spinal interneurons solely by electrical coupling. Neuron 31, 1035–1046
Peter V. Nguyen [email protected]
In Brief
Caged animal concerns Laboratory rodents housed in standard, empty cages exhibit stereotypic behaviors that could indicate brain abnormalities, reported Joseph Garner of the University of California, Davis, at the International Society for Applied Ethology Congress. The stereotypies – pacing, incessant grooming, repetitive cage biting and scratching – are most prevalent in these nocturnal animals at night, and are often underappreciated by researchers who work with animals during the day. As stereotypies in humans are associated with basal ganglia damage, and mice raised in enriched environments have been shown to have more neurons and better memory, these findings have implications for many studies in the neurosciences. LO
Teaching worth a million The Howard Hughes Medical Institute (HHMI) has announced new grants to promote innovative undergraduate science education strategies and to support university research scientists who also make teaching a priority. Eighty-four research universities have been invited to nominate tenured faculty members to compete for one of the 20 US$1 million grants that will be awarded to proposals that infuse education programs with more of the excitement, enthusiasm, creativity and spirit of research strategies. Through http://tins.trends.com
Wellcome Trust sets new standards of conduct Next year, research institutions receiving funding from the Wellcome Trust will have to adhere to new guidelines for good science practice and new procedures for handling cases of misconduct, plagiarism and falsification. Among the changes: the trust might carry out misconduct investigations independently from the investigations carried out by research institutions. The Wellcome Trust guidelines are more extensive than the existing governmental research council guidelines, but as the trust funds nearly 20% of biomedical research in the United Kingdom, the majority of universities will probably adopt the Wellcome Trust stipulations and effectively make them the new British standard. LO
Cyborg: ‘cybernetic + organism’ ?!! Well, no, not yet. However, the successful development of a noninvasive neuroelectronic interface system consisting of an elementary circuit of two neurons synaptically connected to a semiconductor chip presages the advent of an era of neurocomputation and neuroengineering. The study by Zeck and Fromherz at the
A complex role for genetics in autism Autism results from a complex interaction between several different genes involved in brain signaling and development. In a large-scale collaboration between the United States and Europe, researchers have now found that two regions on chromosomes 2 and 7 are strongly linked to autism, and that chromosomes 16 and 17 also contain genes involved in autism although a weaker correlation was observed. Excitement arose from the fact that chromosome 7 is known to be associated with several language disorders. The investigators have announced that trials will now be performed to determine how environmental factors influence these genes to produce the wide range of symptoms that
0166-2236/01/$ – see front matter © 2001 Elsevier Science Ltd. All rights reserved.