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Spring 2010 Vol 1 Issue 2 thenerve The Neuroanatomy of Homosexuality The Religious Brain Neuroscience and the Military The Rise of the Cyborgs Mind and Brain Society The Mind and Brain Society (MBS; formerly known as the BU Organization for the Mind and Brain Sciences) was founded in the fall of 2008 in concert with BU’s new Undergraduate Program in Neuroscience. The group aims to create a network for un- dergraduate students who wish to take an active role in current issues and research. MBS serves as a hub for not only Neuroscience majors, but all students interested in Psychology, Biology, Philosophy, Computer Science, etc. Our goal is to support an ea- ger multidisciplinary undergraduate community with the conversations and resources fundamental to Neuroscience today. Throughout the academic year, MBS hosts events spotlighting many different fac- ets of Neuroscience. We hold discussion sessions during which we informally discuss a topic of interest over coffee; previous topics include “The Neuroscience of Religion” and “NeuroEthics.” The group also hosts research presentations by BU professors and screenings of thought-provoking films containing neuroscience motifs. Cover: Brainbow mouse hippocampus. Image by Tamily Weissman. The Brainbow mouse was produced by Livet J, Weissman TA, Kang H, Draft RW, Lu J, Bennis RA, Sanes JR, Lichtman JW. Nature (2007) 450:56-62. CONTENTS Spring 2010 Vol. 1 Issue 2 RESEARCH IN BRIEF 6 ARTICLES The Rise of the Cyborgs by Darrien Garay 12 Brain Battles: Neuroscience and the Military by Monika Chitre 15 The Religious Brain by Pinkey Shah 19 The Special K Challenge for Depression by Aisha Sohail and Jeff Wessell23 REVIEWS Recognition Memory: One process or two? by Danielle Miller 27 The Neuroanatomy of Homosexuality by Claire Bryson 33 Huemer’s Theory of Perception: Analysis and Objections by Ethan Rubin 37 OPINION Homemade Terror by Darrien Garay 46 SPRING 2010 | 3 FROM THE EDITORS he U.S. media has been consumed by healthcare Editors-In-Chief reform for the past year or so, arriving at a climax Grigori Guitchounts Twith the historic vote in the House of Representa- Kimberly LeVine tives on March 21. Whether or not the new legislation will Editors alleviate the country’s problems remains to be seen. No Neil Datta matter what your opinion on the changes making their way Doug Hidlay through America’s healthcare system, we cannot deny that they will have an impact on our community. Our hopes are Associate Editors that a new system will only enhance the neurological care Lauren Joseph for those around us. Here at The Nerve, we hope you will Monika Chitre take a few minutes to forget about the politics and enjoy the Natalie Banacos science. Jennifer Richardson Having set out to conquer the world by means of study- Frank DeVita ing abroad, our editorial team brings you the Second Issue Artwork from three continents, including Europe and South America. Kayla Ritchie Our goal was to collect articles as far-reaching as our staff. From the relationship of the military with neuroscience to MBS Staff Darrien Garay the neuroanatomy of homosexuality, we are confident you Megan Mataga willThis find andsomething other issues inside of to The stimulate Nerve wouldyour brain. not have been Macayla Donegan possible without the generous help of Howard Eichenbaum, Shea Gillet Paul Lipton, Lindsey Clarkson, Denise Parisi, Zachary Bos, Meghna Majithia and Jarret Frank. Advisors Paul Lipton - Grigori Guitchounts and Kimberly LeVine Zachary Bos Editors-In-Chief 4 | THE NERVE RESEARCH IN BRIEF Vast Parallel Processing in a Retinal Interneuron to support cellular depolar- ization in vivo. As such, this study’s ini- tial morphological data sug- gesting independent pro- cessing functions is lending studies into calcium’s activity significant credence. Further even though transient in- tensewithin Ca2+ A17 activitycells shows can result that, in GABA release, even stud- ies stimulating multiple Ca2+ neurite could not experimen- tallychannel propagate patches any along electronic an A17 information beyond other The eye is a truly wondrous processing organ synaptic contacts in the immediate vicinity, and only composed of six primary cell types separated into two weakly even then. primary plexiform layers. While rods and cones, the actual light responsive cell types, are well character- 150 Givenprimarily that independentthese A17 cells synapses, are able theto receive activity and of more complex in their activity and ability to modulate thisprovide type RBC of amacrine contact-specific cell mimics feedback the atdendritic greater intethan- visualized, horizontal input. In andtheir amacrine study, Grimes cells areet al.significantly examined gration seen in cortical processing interneurons. The morphological, biophysical, and synaptic properties for granted in upper cognitive pathways seems to be asone related specific to type their of amacrinefeedback cells,onto therod A17, bipolar and theircells mirroredfine-tuning even that within has been the essentials studied and of the may visual be takenpath- (RBCs); ultimately, concluding that, at least for the way. This phenomena likely accounts for some of the hundreds of parallel microcircuit feedback loops in stimulate the RBCs and the ability to perceive subtle A17, amacrine cells are uniquely structured to create- changesfine visual in acuity light stimulusseen under even low-light when conditionsthe magnitude that ing on the output of bipolar cells and the overall rod of stimulus is considerably lower than normal visual pathway,order to providewhich is an responsible incredibly forfine vision level ofunder process low parameters. Additionally, by condensing all the mul- ambient light. titude of microfeedback circuits into a single cell, the - visual system reduces the “wiring cost” necessary to ing in combination with cell modeling studies sug- Both fluorescent and electron microscope imag light rod pathway. The Grimes et al. study has laid im- cell extending into the layer of RBCs is able to receive maintain the fine level of feedback needed in the low- synapticgested that output each long,and unbranchingreturn appropriate neurite processing of the A17 responsibilities of the modulatory pathways that al- largely independent of the activity at any but the most lowportant for thegroundwork incredible for diversity finally piecingof signals out and the visual exact discrimination seen in the stimulus-transducing por- cell to reciprocally modify hundreds of inputs with tion of the optical pathway. limitedproximal overlap parts toof neighboringthe cell, allowing points for of synaptica single conA17- tact. Beyond these morphological features limiting — Doug Hidlay the ability of electronic conductance, examination of both sodium and potassium channel response to in- : Grimes WN et al. Retinal Parallel Processors: More than 100 Independent Microcir- do not cause more than a transient depolarization of cuitsoriginal Operate paper within a Single Interneuron. Neuron. 65, localjected portions current ofin neuritesA17 cells in shows vitro, thatwith these little evidencechannels 873–885, 2010. 6 | THE NERVE RESEARCH IN BRIEF Mindblind Eyes in Asperger Syndrome It is well known that autism spectrum disorders ing movement and did not assign a false-belief to the frequently plague sufferers with impairments in com- character in the task. munication and social interaction. A popular hypoth- The results show that adults with Asperger syn- esis breaking into what underlies these impairments drome do not spontaneously predict others’ actions is that autistic children lack Theory of Mind (ToM), in a nonverbal situation. This impairment charac- the ability to assign mental states to oneself or others; terizes mindblindess in autism spectrum disorder that is to say, one’s ability to understand others’ feel- patients. Senju et al suggest that nonverbal mental ings or viewpoints based on the unique set of infor- state assignment skills require spontaneous encoding mation available to one. In the Sally-Anne false-belief of socially relevant information, a skill that individu- task (FBT), a popular test of the Theory of Mind (ToM) als with Asperger syndrome lack, which lends to dif- skill, children are asked to predict a girl’s actions when she looks for a marble that has been moved from its study proposes that it is possible to enhance explicit, usual location without her knowledge. Do children verbalficulty withmental social state interactions. assignment On through the other compensa hand, the- with Asperger syndrome understand Sally-Anne’s tory learning. mental state or are they unable to distinguish their own omniscience from Sally’s misinformed view? — Kimberly LeVine Those with Asperger are, in fact, able to correctly predict Sally’s action, confounding the mindblindess : Senju A, Southgate V, White S, and hypothesis supporting impairment in Theory of Mind. Frith U. Mindblind Eyes: An Absence of Spontaneous Senju et al propose that Asperger patients have Theoryoriginal of paper Mind in Asperger Syndrome. Science the ability to reason through false belief scenarios but nevertheless maintain an impairment as- . 325, signing mental states. The study contrasts 883-885. 2009. results between verbal and nonverbal forms of the false-belief task to trace the divergence of mindblindess between typically develop- ing participants and those with Asperger Syndrome. An earlier study by Southgate et al, us- ing a paradigm similar to the Sally-Ann FBT, sheds light on the tendency of infants to not
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