From mick6116 from googlemail.com Wed Jul 2 09:03:42 2008 From: mick6116 from googlemail.com (Mick Craig) Date: Wed Jul 2 12:55:34 2008 Subject: [Neuroscience] Re: rat brain perfusion and fixation Message-ID: <826ea9f0807020703m2dbbade9l82f3159dc82e496a@mail.gmail.com> > > > > Hello, > > > > I am working on perfusion and fixation of rat brains for the purpose of > Fluoro-Jade staining after the brain has been sectioned with a cryostat. > I am having problems with the brain sections looking like "Swiss > cheese". Has anyone else had this problem? What can I do about this > problem? I am using 4% paraformaldehyde in PBS. Any info/hints will be > greatly appreciated. > > > > Thank you, > > > > Mary Brownson, Ph.D. > > School of Pharmacy After perfusing the brains, I normally sit them in 4% paraformaldehyde for a day, and then put them into a 30% sucrose solution overnight for a second day. This helps to cryoprotect the brains and stop them disintigrating when you cut them. Mick Craig From jonesmat from physiology.wisc.edu Wed Jul 2 17:57:56 2008 From: jonesmat from physiology.wisc.edu (jonesmat) Date: Wed Jul 2 18:45:48 2008 Subject: [Neuroscience] Re: What electrophysiology software are people using? References: <7968f31c-773e-45cf-8cd6-3a1e7cb83a81@j33g2000pri.googlegroups.com> <2ab2068f-c4aa-4e24-b98a-f6d93331dfa2@k30g2000hse.googlegroups.com> <40fbac55-326c-45ae-bc6f-3e0ac6b8f3ae@w4g2000prd.googlegroups.com> Message-ID: <15c3e634-0506-4e1c-9a4c-0073c561d14f@m73g2000hsh.googlegroups.com> On Jun 24, 3:30?pm, Bill wrote: > On Jun 25, 5:42?am, jonesmat wrote: > > > But even with bugs I think it's better than most other packages. I am > > not sure it will do the stats you need (but maybe). We always use > > Prism for KS tests and such, after doing detection & measurement in > > Axograph. > > > Matt > > Wait, hold the phone. Prism can do KS tests? I know it uses them to > test for normality, but I didn't think you could use them to test > between two distributions of your choice. Is that a standard feature? > What version? > > Axograph is good (indeed the best I have seen), and I was at a > neuroscience course in Australia (ACANhttp://acan.jcs.anu.edu.au/acan.html) > with John Clements, the guy who makes Axograph. We were running the PC > version and it still wasn't 100% stable, certainly not stable enough > for me to use it for acquisition of data (though John was bug fixing > throughout the course, so maybe its better now). > > Indeed, if I could get it to work with our CED data loggers I would > probably be trying to convince the boss the use it. Sorry, you're right. Prism uses KS to test for normaility but doesn't have it built in as a standard nonpar test. It does, however, have the Mann-Whitney, which is the one I always use. It compares median ranks and is more powerful than KS, except in the case where there are a lot of identical values between groups (i.e., "ties" - this will presumably be rare in mini analysis, as long as your gain is set reasonably high), or when the two groups differ in shape, rather than in means (i.e., if both have a similar mean, but one has larger tails, so that the cuulative distributions cross near the middle - also rare in mini analysis). I'm using Prism 4.0a (2003), so maybe a newer version would also have KS. Anyway, I think this program rocks, and the help documentation is actually better than any statistics textbook I've ever seen. Plus the author (Harvey Motulsky) has been known to respond helpfully to emails about stats questions (my former postdoc once got a lot of advicefrom him). Axograph X v.1.2 is the latest one, and this is a "synchronized update of both Mac OS X and Windows versions" - according to the recent announcement. The new website is http://www.axograph.com/. Cheers, Matt From bkateb from ibmisps.org Fri Jul 4 15:21:44 2008 From: bkateb from ibmisps.org (International Brain Mapping & Intraoperative Surgical Planning Society (IBMISPS)) Date: Sun Jul 6 12:20:12 2008 Subject: [Neuroscience] CALL FOR ABSTRACTS & PAPER: 5th Annual World Congress for Brain Mapping & Image Guided Therapy (August 26-29 at UCLA-CNSI) Message-ID: <486E8676.00000298@xtinmta06-42.exacttarget.com> IBMISPS Newsletter http://ibmisps.org/ 5th Annual World Congress for Brain Mapping and Image Guided Therapy - Location and Time - Registration - Hotels and Lodging - Deadlines - Scientific Program - Senatorial Support - Contact Us - Unsubscribing - http://ibmisps.org/content.php?x=aboutus About IBMISPS http://ibmisps.org/content.php?x=aboutus Program CommitteeAaron A. Cohen GadolU of INDIANAAlexandra GolbyHARVARDAmir VokshoorThe Spine InstituteBabak KatebIBMISPSBehnam BadieCOHChris MacedoniaTATRC, ARMYDavid F. MooreMAC, The US ARMYDeborah WardenWRAMC, the US ARMYElaine BearerBROWNEdtzabeth BdldtttUNCFarzad MassoudiUCLAFerenc A. JoleszHARVARDHeidi TerrioEACH-Ft CARSON, the US ARMYJean-Jacques LemaireUNIVERSITY OF AUVERGNE, FRANCEJohn HallerNIBIBKayvan FarahaniNCIKen CurleyTATRC, the US ARMYLouis LemieuxUCL, UKMary KratzU. of MICHIGANMichael JaffeeAMEDD, the US ARMYMichael OkunUNIVERSITY OF FLORIDAMike ChenCOHMireille GuyaderFRENCH EMBASSYMitsunori MatsumaeTokai U, JAPANPatrick Soon-ShiongABRAXIS BIOSCIENCEPeter GruenUSCRamesh RamanFDAReed SmithEACH-FT CARSON, The US ARMYSarat ChandraInst. Med. Sci., INDIAShoichiro IshiharaSITAMA U, JAPANShodleh NikzadNASA/JPLVicky YamamotoUSCWalter KoroshetzNINDSWarren GrundfestUCLALocation and Time Location: http://www.cnsi.ucla.edu/ California NanoSystems Institute (CNSI) 570 Westwood Plaza, Building 114 Los Angeles, CA. 90095 Time and Dates: August 26 -29, 2008Topics 4D, Neuro-mathematics and bio-informatics Anatomy Biophotonics Brain Mapping and Intra-operative Surgical Planning using Endoscopy Brain mapping/functional imaging for rehab medicine and PTSD Diffusion Tensor Imaging Ethical issues Functional brain mapping (fMRI, PET...) General surgical issues an case reports Healthcare Policy, Ethics and Regulatory affairs High-field and low-field magnetic resonance Image guided systems Imaging modalities for detecting mild/mod TBI, micro-TBI ISP & Image guided surgery (OR of the future) Magnetic resonance Spectroscopic Imaging Minimally invasive therapy for TBI Molecular and cellular imaging including: the use of nano-particles for stem cell and T-cell imaging. Multi-modality imaging and ultrasound Multimodality imaging for TBI and PTSD (DTI technology,...) Nanoscience, genomics, computational informatics genetics in brain mapping Neural Prosthesis & Robotics (Human Brain machine Interface technology) Neurophysiology (EEG, MEG,...) Operational issues Perfusion imaging, micromagnetic resonance imaging Psychiatry (PTSD,...) Rehabilitation Medicine (neural repair and regeneration for TBI,...Patients) SPECT functional Brain Mapping and histopathology in brain mapping Stereotactic Radiosurgery Transcranial Magnetic Stimulation Vascular & Blood flow imaging Registration Register for the 2008 IBMISPS conference http://ibmisps.org/register.php here to gain access to member services such as abstract submission. Hotels and Lodging Location 1: UCLA Tiverton House (walking distance) 900 Tiverton Ave. Los Angeles, CA 90024-3013 Phone: (310) 794-0151 | Fax: (310) 794-0153 Email: mailto:tivertonhouse@mednet.ucla.edu tivertonhouse@mednet.ucla.edu Website: http://www.tivertonhouse.ucla.edu tivertonhouse.ucla.edu Location 2: Hotel Angeleno (2.35 miles from venue) 170 N. Church Lane Los Angeles , California 90049 P: 310.476.6411 | F: 310.472.1157 Reservations: 1.866.ANGELENO Website: http://www.hotelangeleno.com hotelangeleno.com To make hotel reservations, please click https://reservations.ihotelier.com/crs/g_reservation.cfm?groupID=140728&hotelID=6272 here Deadlines AbstractsThis is just a reminder that the deadline for abstract submission for the 2008 IBMISPS meeting is July 30, 2008. Please login as a member at the top of the http://ibmisps.org/ website , and click http://www.ibmisps.org/content.php?x=papersubmission here for submission guidelines. Please note that you should be http://ibmisps.org/register.php registered as a member prior to submitting your abstract online. Please allow the IBMISPS peer review committee 7 days to review your submission for the meeting. Full PapersPlease note that by presenting in IBMISPS, you are qualified submit a full original paper to our Special Issue of IBMISPS-NeuroImage by December 1, 2008. Submissions are subject to rigorous peer review. You can submit these papers online http://www.elsevier.com/wps/find/journaldescription.cws_home/622925/description#description here at the Elsevier website. Scientific Program The program will be drawn from submitted abstracts and will include categories ranging from basic translational research to multidisciplinary clinical practice and surgery. These categories are listed at the bottom of http://ibmisps.org/content.php?x=aboutus this page . Abstracts will be scored, peer reviewed by prominent members of the program committee who are leaders in the field, and organized as oral presentations and posters. In summary, the deadline for electronic submission of the abstracts is July 30, 2008, while the deadline for the full paper submission is December 1, 2008. Please contact the IBMISPS-NeuroImage managing editor, Babak Kateb at mailto:Bkateb@IBMISPS.Org Bkateb@IBMISPS.Org should you have any questions. Senatorial Support http://www.youtube.com/watch?v=EORCmAU8lGA Here is the Honorable Senator Barbara Boxer's message from last year's conference. Contact Us Babak Kateb Executive Director International Brain Mapping & Intraoperative Surgical Planning (IBMISPS), Global Headquarter, 8159 Santa Monica Blvd. Suite #200 West Hollywood, CA 90046 Tel: (310) 500-6196 Fax: (323) 654-3511 Email us at: mailto:Bkateb@IBMISPS.ORG Bkateb@IBMISPS.ORG Visit us at http://ibmisps.org/ our website Unsubscribing from IBMISPS newsletter Please click the http://cl.exct.net/unsub_center.aspx?s=fe2f157774650c7b701671&j=fe8a117676650c7573&mid=fefa1374736400&lid=febe1c777c600478&jb=ffcf14&ju=%%ex2;joburlid%% here and follow the instructions on the new page to successfully unsubscribe. This email was sent by:IBMISPS 8159 Santa Monica Blvd., Suite 200 West Hollywood, CA, 90046, USA http://cl.exct.net/profile_center.aspx?s=fe2f157774650c7b701671&mid=fefa1374736400&j=fe8a117676650c7573&l=febe1c777c600478&jb=ffcf14&ju=%%ex2;joburlid%% Update Profile From LorenzoPiaHomePage from gmail.com Sun Jul 6 07:21:13 2008 From: LorenzoPiaHomePage from gmail.com (LorenzoPiaHomePage@gmail.com) Date: Sun Jul 6 12:20:18 2008 Subject: [Neuroscience] NEW HOME PAGE Message-ID: Hi, My researchs attempts to clarify the neurocogntive mechanisms underpinning the subjective experience of being aware. In particular I'm focusing on the phenomenological experience of willed actions and space representation. If you're interseted please visit http://lorenzopiahomepage.googlepages.com/ Regards From boris.prilutsky from ap.gatech.edu Mon Jul 14 16:25:40 2008 From: boris.prilutsky from ap.gatech.edu (Priloutski, Boris I) Date: Mon Jul 14 17:13:52 2008 Subject: [Neuroscience] Postdoctoral position at Georgia Tech Message-ID: <039c01c8e5f8$564917a0$284cd78f@BP670> Postdoctoral position at Georgia Institute of Technology, Atlanta, USA The Center for Human Movement Studies at the School of Applied Physiology of Georgia Tech (http://www.ap.gatech.edu/) is inviting applications for a postdoctoral position to work on a project "Sensorimotor Control of Locomotion after Peripheral Nerve Injury". The scope of the project will include investigations of (1) mechanical response of the local musculoskeletal system to peripheral nerve injury and repair, (2) short-term compensation of muscle coordination during the recovery from self-reinnervation of selected ankle extensors in the cat, and (3) contribution of proprioception from intact muscles to adaptation of the motor patterns to the loss of feedback in selected ankle extensors. The research will involve close collaboration with the groups of Dr. Arthur English (Emory University) and T. Richard Nichols (Georgia Tech). The Center for Human Movement Studies has a 6-camera Vicon system, three small Bertec force platforms, and equipment for in vivo recordings of activity, force and fascicle length in selected muscles and for peripheral nerve stimulations and recordings. The appointment will start immediately and be for two years initially and renewable up to a total of 4 years. Successful candidate is expected to have a background in human/animal movement science, biomedical engineering, neurophysiology or related fields. Experience in motion analysis, animal surgery and chronic physiological recordings is beneficial. Existing research programs at the School of Applied Physiology use a systems physiology approach to study movement and mobility at all levels, from molecule to organism. Research areas include muscle and exercise physiology, neural control, biomechanics, and prosthetics and orthotics. Opportunities for collaboration exist on campus and with the Emory School of Medicine, Georgia State University and the Atlanta VA Medical Center. Georgia Tech is one of the top 10 US public research universities and is situated on an attractive 400 acre campus in the heart of Atlanta, a culturally-rich and dynamic city. Please send CV, research summary, and contact information of three references to Boris I. Prilutsky at boris.prilutsky@ap.gatech.edu. -- Boris I. Prilutsky, PhD School of Applied Physiology Georgia Institute of Technology 281 Ferst Drive Atlanta, GA 30332-0356, USA Phone: 404-894-7659 Fax: 404-894-7593 E-mail: boris.prilutsky@ap.gatech.edu From hlee from medsci.usyd.edu.au Sun Jul 20 04:06:50 2008 From: hlee from medsci.usyd.edu.au (Hyunchul Lee) Date: Sun Jul 20 06:05:50 2008 Subject: [Neuroscience] Golgi stain Message-ID: <461465.97466.qm@web31405.mail.mud.yahoo.com> Hi, I need help... I've been trying out a Golgi impregnation protocol- it was my first try and it wasn't great, but it worked... in a tiny corner of my brain anyways... I'd cut it on a freezing microtome. After having a quick look and taking a couple of photos, I decided to leave them in distilled water overnight. I came back the next day, and mounted them, only to find that the staining had vanished with only brown blobs dotting where the cell profiles used to be... so here's a question- does Golgi staining dissolve in water? I was thinking of double staining with immunohistochemistry, but obviously, if the Golgi reaction product dissolves in water in a space of only a few hours, this is impossible- yet I HAVE heard of others doing immunocytochemistry on Golgi-labeled sections... Also- a reddish brown precipitate (which I guess is the silver chromate reaction product of the Golgi stain) forms a coat around my brain, and little label happens deep within the brain (I'm staining tiny black six mouse brains)... is this normal? I am washing my brain for 30 min in distilled water after the chromation step. BTW, here's the protocol I'm using: Gonzalez-Burgos et al., 1992. Golgi method without osmium tetroxide for the study of the central nervous system. Biotechnic & Histochemistry 67 (5):288-296 Thanks for any helpful suggestions! Hyunchul Lee PhD student SystemsNeuroscience Laboratory N121 Anderson Stuart Bldg.(F13) The University of Sydney , NSW, 2006 Email:hlee@medsci.usyd.edu.au From connelly.bill from gmail.com Mon Jul 21 03:36:28 2008 From: connelly.bill from gmail.com (Bill) Date: Mon Jul 21 06:32:34 2008 Subject: [Neuroscience] Re: Golgi stain References: Message-ID: Are you sure you fixed the slices properly? i.e. is it possible you just lysed the cells with the H2O? On Jul 20, 9:06?pm, Hyunchul Lee wrote: > Hi, I need help... > > I've been trying out a Golgi impregnation protocol- it was my first try and it wasn't great, but it worked... > in a tiny corner of my brain anyways... I'd cut it on a freezing microtome. ?After having a quick look and taking > a couple of photos, I decided to leave them in distilled water overnight. > > I came back the next day, and mounted them, only to find that the staining had vanished with only brown blobs dotting > where the cell profiles used to be... so here's a question- does Golgi staining dissolve in water? ?I was thinking of > double staining with immunohistochemistry, but obviously, if the Golgi reaction product dissolves in water in a space of > only a few hours, this is impossible- yet I HAVE heard of others doing immunocytochemistry on Golgi-labeled sections... > > Also- a reddish brown precipitate (which I guess is the silver chromate reaction product of the Golgi stain) forms a coat > around my brain, and little label happens deep within the brain (I'm staining tiny black six mouse brains)... is this normal? > I am washing my brain for 30 min in distilled water after the chromation step. > > BTW, here's the protocol I'm using: > Gonzalez-Burgos et al., 1992. Golgi method without osmium tetroxide for the study of the central nervous system. Biotechnic & Histochemistry 67 (5):288-296 > > Thanks for any helpful suggestions! > > Hyunchul Lee > PhD student > > SystemsNeuroscience Laboratory > N121 Anderson Stuart Bldg.(F13) > The University of Sydney , NSW, 2006 > Email:h...@medsci.usyd.edu.au From hlee from medsci.usyd.edu.au Tue Jul 22 05:07:53 2008 From: hlee from medsci.usyd.edu.au (Hyunchul Lee) Date: Tue Jul 22 19:19:59 2008 Subject: [Neuroscience] Re: Golgi stain Message-ID: <998912.9573.qm@web31408.mail.mud.yahoo.com> Dear Bill, thanks for your suggestion. As embarrassing as it may be to think that it was something so simple- I think you're right. I left another batch of sections in 30% sucrose overnight, and they seem fine. Sorry for causing a ruckus everyone... but I would like to know why people seem so worried about the Golgi product deteriorating... and why many groups (though not all) go to the trouble of doing single-section Golgi staining on immunolabeled sections instead of performing immunolabeling on Golgi impregnated sections. Also, many investigators choose to section paraffin-embedded brains and some papers seem to imply that this is important to maintain the integrity of labeling. The number of different chemical tricks used to preserve Golgi labeling, as well as techniques such as gold-toning and deimpregnation makes me wonder... what makes them necessary? At least for now, I'm one happy dude! Hyunchul Lee PhD student Systems Neuroscience Laboratory N121 Anderson Stuart Bldg. (F13) The University of Sydney, NSW, 2006 Email: hlee@medsci.usyd.edu.au ----- Original Message ---- From: Bill To: neur-sci@magpie.bio.indiana.edu Sent: Monday, July 21, 2008 6:36:28 PM Subject: [Neuroscience] Re: Golgi stain Are you sure you fixed the slices properly? i.e. is it possible you just lysed the cells with the H2O? On Jul 20, 9:06 pm, Hyunchul Lee wrote: > Hi, I need help... > > I've been trying out a Golgi impregnation protocol- it was my first try and it wasn't great, but it worked... > in a tiny corner of my brain anyways... I'd cut it on a freezing microtome. After having a quick look and taking > a couple of photos, I decided to leave them in distilled water overnight. > > I came back the next day, and mounted them, only to find that the staining had vanished with only brown blobs dotting > where the cell profiles used to be... so here's a question- does Golgi staining dissolve in water? I was thinking of > double staining with immunohistochemistry, but obviously, if the Golgi reaction product dissolves in water in a space of > only a few hours, this is impossible- yet I HAVE heard of others doing immunocytochemistry on Golgi-labeled sections... > > Also- a reddish brown precipitate (which I guess is the silver chromate reaction product of the Golgi stain) forms a coat > around my brain, and little label happens deep within the brain (I'm staining tiny black six mouse brains)... is this normal? > I am washing my brain for 30 min in distilled water after the chromation step. > > BTW, here's the protocol I'm using: > Gonzalez-Burgos et al., 1992. Golgi method without osmium tetroxide for the study of the central nervous system. Biotechnic & Histochemistry 67 (5):288-296 > > Thanks for any helpful suggestions! > > Hyunchul Lee > PhD student > > SystemsNeuroscience Laboratory > N121 Anderson Stuart Bldg.(F13) > The University of Sydney , NSW, 2006 > Email:h...@medsci.usyd.edu.au _______________________________________________ Neur-sci mailing list Neur-sci@net.bio.net http://www.bio.net/biomail/listinfo/neur-sci From erocon from gmail.com Tue Jul 22 06:14:18 2008 From: erocon from gmail.com (erocon@gmail.com) Date: Tue Jul 22 19:20:04 2008 Subject: [Neuroscience] PhD. position at Bioengineering group, CSIC - Spain Message-ID: <4bea526d-8b02-4917-8c65-351f4d52984f@l64g2000hse.googlegroups.com> PhD Position and Work description A Ph.D. position is available in the Bioengineering Group of the Consejo Superior de Investigaciones Cient?ficas, Spain. The selected candidate will work in the framework of both international and Spanish projects in the area of BCI. The selected candidate will work in ? New experimental paradigms, signal processing techniques, and pattern recognition procedures to model brain activity and to on-line detect mental states from spontaneous EEG signals. ? Implemention of Electroencephal ography (EEG)-based brain- computer interfaces (BCIs). ? Application of BCIs to compensate or restore human lost functionalities, particularly the suppression of tremor. This work is part of two European and National funded projects, and it will be carried out in a dynamic Bioengineering group leading world- class research on Human Functionality. Candidate profile Candidates must have an outstanding academic record and a University degre e in one of the following specialties: Physics, Electronic Engineering, Biomedical Engineering, Telecommunications Engineering, or Electrical Engineering. The profile of the candidate should cover as much as possible the following distinctive features: - Strong background on one or some of the following techniques: Digital Signal Processing, Pattern Recognition, System Modeling, and Measurement and Instrumentation. - Programming experience in MATLAB? - High motivation for research, originality and initiative - Fluent in English, or fluent in Spanish plus good written and verbal communication skills in English. - Good interpersonal communication skills. Application procedure: Interested applicants should send their CV by e-mail to: E. Rocon, erocon@iai.csic.es From fredo from hotmail.com Sat Jul 26 09:06:58 2008 From: fredo from hotmail.com (Fredo) Date: Sat Jul 26 12:11:16 2008 Subject: [Neuroscience] Backpropagation in biological neurons Message-ID: <-9-dnV6Kdf7ishbVnZ2dnUVZ_tHinZ2d@giganews.com> I've been reading a bit about neurophysiology and neurobiology. A number of texts refer to backpropagation in real neurons, where the signal backpropagates, though significantly attenuated, up the dendrites. I can't seem to find out much detail on the matter, beyond the fact that it exists. In particular, what is the significance? The backpropagation might affect gap junction-connected neurons, but it can't back-propagate through synapses, can it? If it can, what's the mechanism? Surely not neurotransmitter release in the dendrites... Thanks From r_s_norman from _comcast.net Sat Jul 26 09:23:01 2008 From: r_s_norman from _comcast.net (r norman) Date: Sat Jul 26 12:11:21 2008 Subject: [Neuroscience] Re: Backpropagation in biological neurons References: <-9-dnV6Kdf7ishbVnZ2dnUVZ_tHinZ2d@giganews.com> Message-ID: <1icm84hv01a1ed1nfc3o06lpusjnc1hemd@4ax.com> On Sat, 26 Jul 2008 09:06:58 -0500, "Fredo" wrote: >I've been reading a bit about neurophysiology and neurobiology. A number of >texts refer to backpropagation in real neurons, where the signal >backpropagates, though significantly attenuated, up the dendrites. > >I can't seem to find out much detail on the matter, beyond the fact that it >exists. In particular, what is the significance? The backpropagation might >affect gap junction-connected neurons, but it can't back-propagate through >synapses, can it? If it can, what's the mechanism? Surely not >neurotransmitter release in the dendrites... > Yes, most surely neurotransmitter release in the dendrites. There are an enormous number of dendro-dendritic synapses. There are an enormous number of "local" neurons with no axon or with very short axons where the local propagation of potentials does all the work. There are an enormous number of "microcircuits", closely interacting groups of synapses working as a unit within the dendritic field. There are reciprocal synapses : A synapses on B and B synapses back on A right next door. There are serial synapses: A on B and B on C, all in the same microciruit area. G. Shepherd, "The Synaptic Organization of the Brain" is a good resource. From fredo from hotmail.com Sat Jul 26 09:49:39 2008 From: fredo from hotmail.com (Fredo) Date: Sat Jul 26 12:11:25 2008 Subject: [Neuroscience] Re: Backpropagation in biological neurons References: <-9-dnV6Kdf7ishbVnZ2dnUVZ_tHinZ2d@giganews.com> <1icm84hv01a1ed1nfc3o06lpusjnc1hemd@4ax.com> Message-ID: "r norman" wrote in message news:1icm84hv01a1ed1nfc3o06lpusjnc1hemd@4ax.com... > On Sat, 26 Jul 2008 09:06:58 -0500, "Fredo" wrote: > >>I've been reading a bit about neurophysiology and neurobiology. A number >>of >>texts refer to backpropagation in real neurons, where the signal >>backpropagates, though significantly attenuated, up the dendrites. >> >>I can't seem to find out much detail on the matter, beyond the fact that >>it >>exists. In particular, what is the significance? The backpropagation might >>affect gap junction-connected neurons, but it can't back-propagate through >>synapses, can it? If it can, what's the mechanism? Surely not >>neurotransmitter release in the dendrites... >> > > Yes, most surely neurotransmitter release in the dendrites. There are > an enormous number of dendro-dendritic synapses. There are an > enormous number of "local" neurons with no axon or with very short > axons where the local propagation of potentials does all the work. > There are an enormous number of "microcircuits", closely interacting > groups of synapses working as a unit within the dendritic field. There > are reciprocal synapses : A synapses on B and B synapses back on A > right next door. There are serial synapses: A on B and B on C, all > in the same microciruit area. > > G. Shepherd, "The Synaptic Organization of the Brain" is a good > resource. > Okay, that makes sense, I guess. I wasn't thinking in terms of dendrite-to-dendrite communication so much as dendrite-to-axon communication which didn't make as much sense to me. I also wasn't aware that dendrites could release neurotransmitters though after reading your response and doing some quick searching, came across the text, "Dendritic Neurotransmitter Release" edited by M. Ludwig. I'll try to get a copy of "The Synaptic Organization of the Brain". Thanks a ton. From usenet02 from out-of-phase.de Sat Jul 26 10:14:04 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Sat Jul 26 12:11:30 2008 Subject: [Neuroscience] Re: Backpropagation in biological neurons References: <-9-dnV6Kdf7ishbVnZ2dnUVZ_tHinZ2d@giganews.com> Message-ID: <1ikp0nl.118mhaox0rspgN%usenet02@out-of-phase.de> While dendritic neurotransmitter release is one function, backpropagating APs are also considered important in other phenomena. One important thing to consider is that backpropagation can have two separate mechanisms: A merely passive electrotonic spread of actionpotentials from the soma/initiation site into the dendrites. This is often weak and not found in all neurons. Alternatively, voltage sensitive ionchannels in the dendrites can cause an active backpropagation. One role of backprops is the unblocking of NMDA-channels at synapses, allowing them to open when they are activated by glutamate released from the presynapse. This coincidence of pre- and post-synaptic activity can lead to changes in the strength of the involved synapses. You might want to have a look at: M. London and M. H?usser. Dendritic computation. Annual Reviews Neuroscience, 28:503-532, 2005. Best, Christian From r_s_norman from _comcast.net Sat Jul 26 13:06:35 2008 From: r_s_norman from _comcast.net (r norman) Date: Sun Jul 27 13:55:08 2008 Subject: [Neuroscience] Re: Backpropagation in biological neurons References: <-9-dnV6Kdf7ishbVnZ2dnUVZ_tHinZ2d@giganews.com> <1ikp0nl.118mhaox0rspgN%usenet02@out-of-phase.de> Message-ID: On Sat, 26 Jul 2008 16:14:04 +0100, usenet02@out-of-phase.de (Christian Wilms) wrote: >While dendritic neurotransmitter release is one function, >backpropagating APs are also considered important in other phenomena. > >One important thing to consider is that backpropagation can have two >separate mechanisms: A merely passive electrotonic spread of >actionpotentials from the soma/initiation site into the dendrites. This >is often weak and not found in all neurons. Alternatively, voltage >sensitive ionchannels in the dendrites can cause an active >backpropagation. > >One role of backprops is the unblocking of NMDA-channels at synapses, >allowing them to open when they are activated by glutamate released from >the presynapse. This coincidence of pre- and post-synaptic activity can >lead to changes in the strength of the involved synapses. > >You might want to have a look at: > >M. London and M. H?usser. Dendritic computation. Annual Reviews >Neuroscience, 28:503-532, 2005. Yes, that one I forgot about completely. My bad, it is a very important phenomenon. From david_olmsted from sbcglobal.net Sun Jul 27 07:43:19 2008 From: david_olmsted from sbcglobal.net (David Olmsted) Date: Sun Jul 27 13:55:13 2008 Subject: [Neuroscience] Backpropagation in biological neurons In-Reply-To: <-9-dnV6Kdf7ishbVnZ2dnUVZ_tHinZ2d@giganews.com> Message-ID: <34335.86471.qm@web82805.mail.mud.yahoo.com> Fredo wrote: I've been reading a bit about neurophysiology and neurobiology. A number of texts refer to backpropagation in real neurons, where the signal backpropagates, though significantly attenuated, up the dendrites. I can't seem to find out much detail on the matter, beyond the fact that it exists. In particular, what is the significance? The backpropagation might affect gap junction-connected neurons, but it can't back-propagate through synapses, can it? If it can, what's the mechanism? Surely not neurotransmitter release in the dendrites... Thanks Back-propagation is the natural result of injecting any ionic current into a neuron. These ions will spread out in both directions. In neurons 3 ionic currents do this: Sodium ions, Potassium ions, and Calcium ions. Sodium ions are the "normal" neural charge, Potassium ions reverse the Sodium effects and thus are considered an inhibitory response, Calcium ions are involved in neural modulation and adaptability. As others have mentioned the Sodium back-propagation can be actively amplified (the NMDA receptors) and modulated further via dendritic micro-circuits. Yet you asked about the significance of all this. The answer is that the interactions of these back-propagating currents determine the response characteristics of the neuron which in turn is governed by the purpose of the neuron its local circuit which is in turn governed by the behavioral needs of the animal. By response characteristics I mean control over latency, time horizon, burstiness, frequency, connective type (more Sum-like or OR-like) etc. for a given set of input types, If you are really interested in how these back-propagating currents interact and want to play with their various control parameters I have a demo brain circuit simulation program for windows computers at my site (softstatemagic.com) where you can create your own neuron or use a neuron in an example brain circuit that you can download. And in an answer to Stephen Wolstenholme I hope you can see that the backpropagation technique used in artificial neuron networks is nothing like the neural backpropagation in question here. Dave _____________________________________________________________ Brain Circuit Simulation Resources: http://www.softstatemagic.com From bkateb from ibmisps.org Tue Jul 29 03:09:46 2008 From: bkateb from ibmisps.org (International Brain Mapping & Intraoperative Surgical Planning Society (IBMISPS)) Date: Tue Jul 29 12:39:47 2008 Subject: [Neuroscience] CALL FOR ABSTRACTS & PAPER: 5th Annual World Congress for Brain Mapping & Image Guided Therapy (August 26-29 at UCLA-CNSI) Message-ID: <488ED06E.00000E16@xtinmta03-36.exacttarget.com> IBMISPS Newsletter http://ibmisps.org/ 5th Annual World Congress for Brain Mapping and Image Guided Therapy - Location and Time - Registration - Hotels and Lodging - Deadlines - Scientific Program - Senatorial Support - Contact Us - Unsubscribing - http://ibmisps.org/content.php?x=aboutus About IBMISPS http://ibmisps.org/content.php?x=aboutus Program CommitteeAaron A. Cohen GadolU of INDIANAAlexandra GolbyHARVARDAmir VokshoorThe Spine InstituteBabak KatebIBMISPSBehnam BadieCOHChris MacedoniaTATRC, ARMYDavid F. MooreMAC, The US ARMYDeborah WardenWRAMC, the US ARMYElaine BearerBROWNEdtzabeth BdldtttUNCFarzad MassoudiUCLAFerenc A. JoleszHARVARDHeidi TerrioEACH-Ft CARSON, the US ARMYJean-Jacques LemaireUNIVERSITY OF AUVERGNE, FRANCEJohn HallerNIBIBKayvan FarahaniNCIKen CurleyTATRC, the US ARMYLouis LemieuxUCL, UKMary KratzU. of MICHIGANMichael JaffeeAMEDD, the US ARMYMichael OkunUNIVERSITY OF FLORIDAMike ChenCOHMireille GuyaderFRENCH EMBASSYMitsunori MatsumaeTokai U, JAPANPatrick Soon-ShiongABRAXIS BIOSCIENCEPeter GruenUSCRamesh RamanFDAReed SmithEACH-FT CARSON, The US ARMYSarat ChandraInst. Med. Sci., INDIAShoichiro IshiharaSITAMA U, JAPANShodleh NikzadNASA/JPLVicky YamamotoUSCWalter KoroshetzNINDSWarren GrundfestUCLALocation and Time Location: http://www.cnsi.ucla.edu/ California NanoSystems Institute (CNSI) 570 Westwood Plaza, Building 114 Los Angeles, CA. 90095 Time and Dates: August 26 -29, 2008Topics 4D, Neuro-mathematics and bio-informatics Anatomy Biophotonics Brain Mapping and Intra-operative Surgical Planning using Endoscopy Brain mapping/functional imaging for rehab medicine and PTSD Diffusion Tensor Imaging Ethical issues Functional brain mapping (fMRI, PET...) General surgical issues an case reports Healthcare Policy, Ethics and Regulatory affairs High-field and low-field magnetic resonance Image guided systems Imaging modalities for detecting mild/mod TBI, micro-TBI ISP & Image guided surgery (OR of the future) Magnetic resonance Spectroscopic Imaging Minimally invasive therapy for TBI Molecular and cellular imaging including: the use of nano-particles for stem cell and T-cell imaging. Multi-modality imaging and ultrasound Multimodality imaging for TBI and PTSD (DTI technology,...) Nanoscience, genomics, computational informatics genetics in brain mapping Neural Prosthesis & Robotics (Human Brain machine Interface technology) Neurophysiology (EEG, MEG,...) Operational issues Perfusion imaging, micromagnetic resonance imaging Psychiatry (PTSD,...) Rehabilitation Medicine (neural repair and regeneration for TBI,...Patients) SPECT functional Brain Mapping and histopathology in brain mapping Stereotactic Radiosurgery Transcranial Magnetic Stimulation Vascular & Blood flow imaging Registration Register for the 2008 IBMISPS conference http://ibmisps.org/register.php here to gain access to member services such as abstract submission. Hotels and Lodging Location 1: UCLA Tiverton House (walking distance) 900 Tiverton Ave. Los Angeles, CA 90024-3013 Phone: (310) 794-0151 | Fax: (310) 794-0153 Email: mailto:tivertonhouse@mednet.ucla.edu tivertonhouse@mednet.ucla.edu Website: http://www.tivertonhouse.ucla.edu tivertonhouse.ucla.edu Location 2: Hotel Angeleno (2.35 miles from venue) 170 N. Church Lane Los Angeles , California 90049 P: 310.476.6411 | F: 310.472.1157 Reservations: 1.866.ANGELENO Website: http://www.hotelangeleno.com hotelangeleno.com To make hotel reservations, please click https://reservations.ihotelier.com/crs/g_reservation.cfm?groupID=140728&hotelID=6272 here Deadlines AbstractsThis is just a reminder that the deadline for abstract submission for the 2008 IBMISPS meeting is July 30, 2008. Please login as a member at the top of the http://ibmisps.org/ website , and click http://www.ibmisps.org/content.php?x=papersubmission here for submission guidelines. Please note that you should be http://ibmisps.org/register.php registered as a member prior to submitting your abstract online. Please allow the IBMISPS peer review committee 7 days to review your submission for the meeting. Full PapersPlease note that by presenting in IBMISPS, you are qualified submit a full original paper to our Special Issue of IBMISPS-NeuroImage by December 1, 2008. Submissions are subject to rigorous peer review. You can submit these papers online http://www.elsevier.com/wps/find/journaldescription.cws_home/622925/description#description here at the Elsevier website. Scientific Program The program will be drawn from submitted abstracts and will include categories ranging from basic translational research to multidisciplinary clinical practice and surgery. These categories are listed at the bottom of http://ibmisps.org/content.php?x=aboutus this page . Abstracts will be scored, peer reviewed by prominent members of the program committee who are leaders in the field, and organized as oral presentations and posters. In summary, the deadline for electronic submission of the abstracts is July 30, 2008, while the deadline for the full paper submission is December 1, 2008. Please contact the IBMISPS-NeuroImage managing editor, Babak Kateb at mailto:Bkateb@IBMISPS.Org Bkateb@IBMISPS.Org should you have any questions. Senatorial Support http://www.youtube.com/watch?v=EORCmAU8lGA Here is the Honorable Senator Barbara Boxer's message from last year's conference. Contact Us Babak Kateb Executive Director International Brain Mapping & Intraoperative Surgical Planning (IBMISPS), Global Headquarter, 8159 Santa Monica Blvd. Suite #200 West Hollywood, CA 90046 Tel: (310) 500-6196 Fax: (323) 654-3511 Email us at: mailto:Bkateb@IBMISPS.ORG Bkateb@IBMISPS.ORG Visit us at http://ibmisps.org/ our website Unsubscribing from IBMISPS newsletter Please click the http://cl.exct.net/unsub_center.aspx?s=fe2f157774650c7b701671&j=fe9611767364007c76&mid=fefa1374736400&lid=febe1c777c600478&jb=ffcf14&ju=%%ex2;joburlid%% here and follow the instructions on the new page to successfully unsubscribe. This email was sent by:IBMISPS 8159 Santa Monica Blvd., Suite 200 West Hollywood, CA, 90046, USA http://cl.exct.net/profile_center.aspx?s=fe2f157774650c7b701671&mid=fefa1374736400&j=fe9611767364007c76&l=febe1c777c600478&jb=ffcf14&ju=%%ex2;joburlid%% Update Profile From connelly.bill from gmail.com Thu Jul 31 04:42:12 2008 From: connelly.bill from gmail.com (Bill) Date: Thu Jul 31 10:25:05 2008 Subject: [Neuroscience] What can I fill neurons with to disrupt vesicle release? Message-ID: <7fd87241-2996-4a07-88e1-8cb713aaa9cb@v39g2000pro.googlegroups.com> Hi, I need something to put in my intracellular patch solution to stop a neuron in a slice releasing GABA. I don't want to use BAPTA because it will mess with Calcium activated K channels. Botox and Tetanus toxins are possibilities, but they both make me a little nervous (not because they are deadly, but because they are expensive (botox) and because they don't hit all synapses (tetanus) and I'm not sure how many uses I'd get out of one vial). Anything else? Thanks.