Life Sciences Commons^™

Task-Invariant Brain Responses To The Social Value Of Faces., Alex Todorov, Chris Said, Nicholas Oosterhof, Andrew Engell

Andrew Engell

Autism Spectrum Traits In The Typical Population Predict Structure And Function In The Posterior Superior Temporal Sulcus., Elisabeth Von Dem Hagen, Lauri Nummenmaa, R Yu, Andrew Engell, Michael Ewbank, Andy Calder

Andrew Engell

A Comparison Of Three Computer-Based Methods Used To Determine Emg Signal Amplitude, Doug Renshaw

Doug Renshaw

No abstract provided.

Motor Neuron Synapse And Axon Defects In A C. Elegans Alpha-Tubulin Mutant, Renee Baran, Liliana Castelblanco, Garland Tang, Ian Shapiro, Alexandr Goncharov, Yishi Jin

Renee Baran

Regulation of microtubule dynamics underlies many fundamental cellular mechanisms including cell division, cell motility, and transport. In neurons, microtubules play key roles in cell migration, axon outgrowth, control of axon and synapse growth, and the regulated transport of vesicles and structural components of synapses. Loss of synapse and axon integrity and disruption of axon transport characterize many neurodegenerative diseases. Recently, mutations that specifically alter the assembly or stability of microtubules have been found to directly cause neurodevelopmental defects or neurodegeneration in vertebrates. We report here the characterization of a missense mutation in the C-terminal domain of C. elegans alpha-tubulin, tba-1(ju89), …

Amygdala And Dorsomedial Prefrontal Cortex Responses To Appearance-Based And Behavior-Based Person Impressions., Sean Baron, M Gobinni, Andrew Engell, Alex Todorov

Andrew Engell

Distributed Representations Of Dynamic Facial Expressions In The Superior Temporal Sulcus., Chris Said, Chris Moore, Andrew Engell, Alex Todroov, James Haxby

Andrew Engell

Brain, Mind And Behaviour - Emerging Biological Connections, Amresh Srivastava

Amresh Srivastava

No abstract provided.

Connectivity Analysis Reveals A Cortical Network For Eye Gaze Perception., Lauri Nummenmaa, Luca Passamonti, James Rowe, Andrew Engell, Andy Calder

Andrew Engell

Autism-Like Behavioral Phenotypes In Btbr Ttf/J Mice. Genes, Hewlet Mcfarlane

Hewlet McFarlane

No abstract provided.

The Effects Of Prenatal Stress On Motivation In The Rat Pup, Howard Cromwell

Howard Casey Cromwell

Exposure to prenatal stress (PNS) has been shown to induce a set of psychological and behavioral changes in developing offspring. We used the rodent model to investigate whether PNS produces changes in the ability of the pup to express social motivation.We used a set of behavioral tasks including monitoring ultrasonic vocalizations after isolation, a conditioned place preference, and a novel and familiar odor approach test. Pregnant Long–Evans rats were exposed to an unpredictable, variable stressor twice daily during the third week of gestation. Isolation vocalizations were assessed on postnatal day (PND) 10. Pup affinity for the dam was evaluated on …

Understanding Evaluation Of Faces On Social Dimensions., Alex Todorov, Said Chris, Andrew Engell, Nicholas Oosterhof

Andrew Engell

Nonclassical, Distinct Endocytic Signals Dictate Constitutive And Pkc-Regulated Neurotransmitter Transporter Internalization, Haley Melikian

Haley Melikian

Neurotransmitter transporters are critical for synaptic neurotransmitter inactivation. Transporter inhibitors markedly increase the duration and magnitude of synaptic transmission, underscoring the importance of transporter activity in neurotransmission. Recent studies indicate that membrane trafficking dynamically governs neuronal transporter cell-surface presentation in a protein kinase C-regulated manner, suggesting that transporter trafficking profoundly affects synaptic signaling. However, the molecular architecture coupling neurotransmitter transporters to the endocytic machinery is not defined. Here, we identify nonclassical, distinct endocytic signals in the dopamine transporter (DAT) that are necessary and sufficient to drive constitutive and protein kinase C-regulated DAT internalization. The DAT internalization signal is conserved across …

The Neural Bases Of Cognitive Conflict And Control In Moral Judgment., Joshua Greene, Leigh Nystrom, Andrew Engell, John Darley, Jon Cohen

Andrew Engell

Syd-1, A Presynaptic Protein With Pdz, C2 And Rhogap-Like Domains, Specifies Axon Identity In C. Elegans, Steven Hallam, Alexandr Goncharov, Jason Mcewen, Renee Baran, Yishi Jin

Renee Baran

Axons are defined by the presence of presynaptic specializations at specific locations. We show here that loss-of-function mutations in the C. elegans gene syd-1 cause presynaptic specializations to form in the dendritic processes of GABA-expressing motor neurons during initial differentiation. At a later developmental stage, however, syd-1 is not required for the polarity respecification of a subset of these neurons. The SYD-1 protein contains PDZ, C2 and rho–GTPase activating protein (GAP)-like domains, and is localized to presynaptic terminals in mature neurons. A truncated SYD-1 that lacks the rhoGAP domain interferes with neurite outgrowth and guidance. Our data indicate that syd-1 …

Getting A Grip On Liprins, Renee Baran, Yishi Jin

Renee Baran

Two papers in this issue of Neuron add a new dimension to our understanding of liprin and LAR RPTP function during synapse formation. Kaufmann et al. (2002) present evidence that Dliprin-α interacts with Dlar to regulate presynaptic morphogenesis of the Drosophila neuromuscular junction. Wyszynski et al. (2002) demonstrate that mammalian liprin-α1 forms a complex with the PDZ protein GRIP and LAR in both pre- and postsynaptic compartments of hippocampal neurons and is required for the clustering of the GluR2 glutamate receptor in dendritic spines.

Genes That Guide Growth Cones Along The C. Elegans Ventral Nerve Cord, Bruce Wightman, Renee Baran, Gian Garriga

Renee Baran

During nervous system development, growth cone pioneering and fasciculation contribute to nerve bundle structure. Pioneer growth cones initially navigate along neuroglia to establish an axon scaffold that guides later extending growth cones. In C. elegans, the growth cone of the PVPR neuron pioneers the left ventral nerve cord bundle, providing a path for the embryonic extensions of the PVQL and AVKR growth cones. Later during larval development, the HSNL growth cone follows cues in the left ventral nerve cord bundle provided by the PVPR and PVQL axons. Here we show that mutations in the genes enu-1, fax-1, unc-3, unc-30, unc-42 …

Neuromuscular Junction Development In The Cutaneous Pectoris Muscle Of Rana Catesbeiana, Diana Linden, Susan Jerian, Michael Letinsky

Diana Linden

Synaptic specializations were studied in the developing cutaneous pectoris muscle of Rana catesbeiana tadpoles and froglets to correlate nerve terminal morphology (by light and electron microscopy), accumulation of acetylcholine receptors, and the ability of the muscle to contract following nerve stimulation. This correlated approach was used to determine the developmental timing and possible causal relationship of events in nerve and muscle maturation at the neuromuscular junction. Initially, the cutaneous pectoris nerve trunk was present in the undifferentiated presumptive cutaneous pectoris mesenchyme, prior to muscle maturation. At stage XII when the muscle was first able to contract weakly in response to …

Correlated Muscle And Nerve Development In The Bullfrog Cutaneous Pectoris, Diana Linden, Michael Letinsky

Diana Linden

The development of the cutaneous pectoris muscle was studied and compared with the differentiation of its peripheral nerve in bullfrog (Rana catesbeiana) tadpoles and frogs by light and electron microscopic techniques. This muscle preparation was chosen for this study because it possesses a number of advantages for (and has become a model system for) the study of correlated nerve-muscle development. At the earliest stage examined (stage XI) the presumptive muscle did not contain any contractile or morphologically distinguishable myotubes, but was contacted by the well-defined cutaneous pectoris nerve trunk. Myotubes were present at stage XII, the same time that nerve-associated …

Rapid Decline In Acetylcholine Release And Content Of Rat Extensor Digitorum Longus Muscle After Denervation, Diana Linden, Michael Newton, Alan Grinnell, Donald Jenden

Diana Linden

The amount of acetylcholine (ACh) and choline (Ch) in normal and denervated rat extensor digitorum longus (EDL) muscles, as well as that released spontaneously from these muscles, was determined by an extremely sensitive gas chromatographicmass spectrometric assay method. We found decreases in ACh content and spontaneous, resting ACh release as early as 8 h after denervation. The ACh content decreased to a plateau of 30% of control by 11 h; ACh release attained a plateau of 50% of control several hours later. These results showed that in denervated EDL muscles ACh content and spontaneous release (measured biochemically) decreased before nerve-evoked …

Biosynthesis And Degradation Of Acetylcholine Receptors In Rat Skeletal Muscles. Effects Of Electrical Stimulation, Diana Linden, D.M. Fambrough

Diana Linden

Synthesis and degradation of acetylcholine receptors in rat skeletal muscles were measured in organ culture. The rate of de novo biosynthesis and incorporation of acetylcholine receptors into extrajunctional membranes of denervated muscles was measured by determining the rate of appearance of [1] [2H, 13C, 15N]-acetylcholine receptors when muscles were cultured in medium containing [1] [2H, 13C, 15N]-amino acids. Denervated extensor digitorum longus and soleus muscles were found to synthesize new receptors for several days in organ culture at an average rate of 1.4%/h. The degradation rates for extrajunctional and junctional acetylcholine receptors were estimated by irreversibly labeling acétylcholine receptors on …

A Forebrain Visual Projection In The Frog (Rana Pipiens), Edward Gruberg, Victor Ambros

Victor R. Ambros

In the frog (Rana pipiens) using a modification of the Fink-Heimer degeneration stain, a projection was traced from the lateral anterior thalamus via the lateral forebrain bundle to the ipsilateral striatum in the ventrolateral area of the forebrain. Striatal degeneration extended from the anterior commissure to the olfactory bulb. Single-unit microelectrode recording revealed that this area contained visual units that responded to the on and off of light.