Difference between revisions of "Previous weeks"

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== Previous Semesters ==
 
== Previous Semesters ==
 
+
<h3>[[2011]]</h3>
 
<h3>[[Winter 2010]]</h3>
 
<h3>[[Winter 2010]]</h3>
 
<h3>[[Fall 2010]]</h3>
 
<h3>[[Fall 2010]]</h3>

Revision as of 00:39, 29 November 2011

Contents

2011

January

February

Feb 25th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title :A selective role for dopamine in stimulus–reward learning

Speaker: Michael Faneslow

Summary: Flagel et al Nature 469, 53–57 (06 January 2011)

Relevant Information:

Paper

Supp



March

Mar 4th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : Maladaptive Cortical Plasticity and Plasticity

Speaker: Dean Buonomano

Summary: Engineer ND, Riley JR, Seale JD, Vrana WA, Shetake JA, Sudanagunta SP, Borland MS, Kilgard MP (2011) Nature 470:101-104. Reversing pathological neural activity using targeted plasticity

Relevant Information:

Paper


Mar 11th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : Memory enhancement and PKM Zeta

Speaker: Yong-Seok Lee

Summary: Yong-Seok Lee will present the newest paper from the Dudai Lab regarding overexpression of PKM in the neocortex and its enhancement of LTM.


Relevant Information:

Paper


Mar 18th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : Notch Signaling

Speaker: Kelsey Martin

Summary: Notch signaling plays critical roles during the development of the nervous system. Several studies have suggested that Notch signaling in neurons is also involved in learning and memory and synaptic plasticity in the mature brain. However, these studies have been suggestive rather than conclusive. Moreover, studies from Ben Barres indicate that Notch receptor and ligands are expressed at very low levels in mature neurons, and at very high levels in glia. I will present a paper from Nick Gaiano's lab that argues that Notch signals from synapse to nucleus in mature hippocampal neurons and that this signaling is required for long-term potentiation and memory acquisition. Gaiano's data further indicates that the immediate early gene arc regulates Notch signaling in neurons.

The reference for the primary paper is:

Activity-induced notch signaling in neurons requires arc/arg3.1 and is essential for synaptic plasticity in hippocampal networks.

Relevant Information:

Paper

Review


April

01st Apr


Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : A critical role for IGF-II in memory consolidation and enhancement

Speaker: Ravi Ponnusamy

Summary: not provided

Relevant Information:

Paper


08th Apr


Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : The dendritic branch is the preferred integrative unit for protein synthesis-dependent LTP.

Speaker: Walter Babiec

Summary: The late-phase of long-term potentiation (L-LTP), the cellular correlate of long-term memory, induced at some synapses facilitates L-LTP expression at other synapses receiving stimulation too weak to induce L-LTP by itself. Using glutamate uncaging and two-photon imaging, we demonstrate that the efficacy of this facilitation decreases with increasing time between stimulations, increasing distance between stimulated spines and with the spines being on different dendritic branches. Paradoxically, stimulated spines compete for L-LTP expression if stimulated too closely together in time. Furthermore, the facilitation is temporally bidirectional but asymmetric. Additionally, L-LTP formation is itself biased toward occurring on spines within a branch. These data support the Clustered Plasticity Hypothesis, which states that such spatial and temporal limits lead to stable engram formation, preferentially at synapses clustered within dendritic branches rather than dispersed throughout the dendritic arbor. Thus, dendritic branches rather than individual synapses are the primary functional units for long-term memory storage

Relevant Information:

Paper

Supp


Apr 15th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : Mushroom Body Output Neurons Encode Odor-Reward Associations

Speaker: David Glanzman

Summary: The paper describes neural correlates of odor representation and olfactory reward learning in honeybees using both population and single unit recording from the mushroom bodies.

Relevant Information: Paper


Apr 22nd

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title :From Drosophila olfaction to a general circuit model for behavioral habituation.

Speaker: Mani Ramaswami

Summary:

Relevant Information:


Date: Apr 27th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title :The role of Thorase in the surface expression of glutamate receptors and its implications for synaptic plasticity and behavior

Speaker: Adam Roberts

Summary: Zhang et al., 2011 indicate that the AAA+ ATPase Thorase is required for the internalization of AMPARs by dissociating the GRIP1-GluR2 interaction. Genetic manipulation of Thorase expression modifies the surface expression of GluR1 and GluR2 in an ATP-dependent manner. Thorase KO mice have enhanced LTP, deficits in LTD, and larger AMPAR-dependent currents. These alterations in nervous system function result in deficits in learning and memory.

Relevant Information:

Paper


May

Date: May 13th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title :The role of Thorase in the surface expression of glutamate receptors and its implications for synaptic plasticity and behavior

Speaker: Adam Roberts

Summary: Zhang et al., 2011 indicate that the AAA+ ATPase Thorase is required for the internalization of AMPARs by dissociating the GRIP1-GluR2 interaction. Genetic manipulation of Thorase expression modifies the surface expression of GluR1 and GluR2 in an ATP-dependent manner. Thorase KO mice have enhanced LTP, deficits in LTD, and larger AMPAR-dependent currents. These alterations in nervous system function result in deficits in learning and memory.

Relevant Information:

Paper


Date: May 17th

Time 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title: Action-Potential Modulation During Axonal Conduction

Speaker: Besim Ugzil"

Summary: Once initiated near the soma, an action potential (AP) is thought to propagate autoregeneratively and distribute uniformly over axonal arbors. We challenge this classic view by showing that APs are subject to waveform modulation while they travel down axons. Using fluorescent patch-clamp pipettes, we recorded APs from axon branches of hippocampal CA3 pyramidal neurons ex vivo. The waveforms of axonal APs increased in width in response to the local application of glutamate and an adenosine A1 receptor antagonist to the axon shafts, but not to other unrelated axon branches. Uncaging of calcium in periaxonal astrocytes caused AP broadening through ionotropic glutamate receptor activation. The broadened APs triggered larger calcium elevations in presynaptic boutons and facilitated synaptic transmission to postsynaptic neurons. This local AP modification may enable axonal computation through the geometry of axon wiring.

Releavant Information:

Paper


Date: May 17th

Time 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title: Action-Potential Modulation During Axonal Conduction

Speaker: Besim Ugzil"

Summary: Once initiated near the soma, an action potential (AP) is thought to propagate autoregeneratively and distribute uniformly over axonal arbors. We challenge this classic view by showing that APs are subject to waveform modulation while they travel down axons. Using fluorescent patch-clamp pipettes, we recorded APs from axon branches of hippocampal CA3 pyramidal neurons ex vivo. The waveforms of axonal APs increased in width in response to the local application of glutamate and an adenosine A1 receptor antagonist to the axon shafts, but not to other unrelated axon branches. Uncaging of calcium in periaxonal astrocytes caused AP broadening through ionotropic glutamate receptor activation. The broadened APs triggered larger calcium elevations in presynaptic boutons and facilitated synaptic transmission to postsynaptic neurons. This local AP modification may enable axonal computation through the geometry of axon wiring.

Relevant Information:

Paper


Date: May 27th

Time 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title: "What makes a place cell?"

Speaker: Justin Shobe"

Summary: Once initiated near the soma, an action potential (AP) is thought to propagate autoregeneratively and distribute uniformly over axonal arbors. We challenge this classic view by showing that APs are subject to waveform modulation while they travel down axons. Using fluorescent patch-clamp pipettes, we recorded APs from axon branches of hippocampal CA3 pyramidal neurons ex vivo. The waveforms of axonal APs increased in width in response to the local application of glutamate and an adenosine A1 receptor antagonist to the axon shafts, but not to other unrelated axon branches. Uncaging of calcium in periaxonal astrocytes caused AP broadening through ionotropic glutamate receptor activation. The broadened APs triggered larger calcium elevations in presynaptic boutons and facilitated synaptic transmission to postsynaptic neurons. This local AP modification may enable axonal computation through the geometry of axon wiring.

Releavant Information: Paper


June

Date: Jun 17th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : "Insulin Signaling and Dietary Restriction Differentially Influence the Decline of Learning and Memory with Age"

Speaker: Kelsey Martin

Summary: This paper from Coleen Murphy's lab at Princeton describes a novel assay for short and long-term associative memory in the worm c. elegans. Using this assay, the authors show that long-term memory declines very early in c elegans, before any deficits in chemotaxis or motility. Analysis of genetic mutants identifies a specific role for CREB during long-term memory, and further reveals that long-term memory is differentially regulated by the insulin/IGF-1 and dietary restriction longevity pathways.

Relevant Information:

Paper


July

Date: Jul 08th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : "The Origin of Time (in the Songbird Motor Pathway)"

Speaker: Michael A. Long

Summary: Not Provided

Relevant Information:

Lab Homepage



Date: Jul 22nd

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : ""Maps for navigating published work and informing experiment planning""

Speaker: Alcino J Silva and Anthony Landreth

Summary: The increasing volume and complexity of published studies in neuroscience have made it difficult to determine what is known, what is uncertain, and how to contribute effectively to one’s field. Therefore, there is a pressing need for strategies to derive simplified useful representations (i.e. maps) of previous findings and to help experiment planning. Toward these goals, we introduce a framework for classifying experiments and an approach for integrating experimental results based on implicit and explicit research practices in molecular and cellular studies of cognitive function. The development and explicit use of approaches like this one will enable researchers to systematically identify convergent evidence critical for assembling maps of published information. These maps will not only provide succinct summaries of published information, they will also be invaluable during experiment planning.

Relevant Information:

Internally circulated PDF (check your LMP email)


Date: Jul 29th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : ""A neural prosthesis for memory? ""

Speaker: Dean Buonomano

Summary: A discussion on the following paper:

A cortical neural prosthesis for restoring and enhancing memory.

Berger TW, Hampson RE, Song D, Goonawardena A, Marmarelis VZ, Deadwyler SA, Journal of Neural Engineering 8:046017 (2011).

Relevant Information:

http://iopscience.iop.org/1741-2552/8/4/046017/pdf/1741-2552_8_4_046017.pdf


August

Date: Aug 05th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : ""Intact Performance on Feature-Ambiguous Discriminations in Rats with Lesions of the Perirhinal Cortex ""

Speaker: Walter Babiec

Summary: clark et al., have developed a behavioral paradigm for the rat that makes it possible to separate the evaluation of memory functions from the evaluation of perceptual functions. Animals were given extensive training on an automated two-choice discrimination task and then maintained their memory performance at a high level while interpolated probe trials tested visual perceptual ability. The probe trials systematically varied the degree of feature ambiguity between the stimuli. As feature ambiguity increased, performance declined in an orderly, monotonic manner. Bilateral lesions of the perirhinal cortex fully spared the capacity to make feature-ambiguous discriminations and the performance of lesioned and intact animals was indistinguishable at every difficulty level. In contrast, the perirhinal lesions did impair recognition memory. The findings suggest that the perirhinal cortex is important for memory and not for perceptual functions.


Relevant Information:

http://www.cell.com/neuron/abstract/S0896-6273(11)00197-8?switch=standard


Date : Aug 12th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : " Mushroom body efferent neurons responsible for aversive olfactory memory retrieval in Drosophila "

Speaker: David Glanzman

Summary: In this paper Preat and colleagues identify specific neurons in the fly's brain that are essential for the retrieval of a conditioned olfactory memory. These neurons (MB-V2) are found in the mushroom bodies of the Drosophila brain, an area previously identified as critical for olfactory conditioning, during which flies learn to avoid an odor that is paired with shock. Interestingly, the MB-V2 neurons, although essential for the retrieval of both short-term and long-lasting memory, are not required for either memory formation or memory consolidation. The authors propose that MB-V2 neurons recruit the olfactory pathway involved in innate odor avoidance during memory retrieval.

Relevant Information:

Nat. Neurosci. (2011) vol. 14 (7) pp. 903-10



Date: Aug 19th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : " Drosophila mutants undercover functional specificity in mushroom body architecture and a novel role for Importin- (alpha)2 in mushroom body development and classical conditioning "

Speaker: Christine Serway

Summary: The interplay between brain anatomy, neural network organization and behavior has been well studied in Drosophila for over three decades. The first experimental evidence implicating the mushroom bodies (MBs) as centers of sensory integration and association in flies came from anatomical and behavioral work on brain structure mutants. Here we present a detailed analysis of three genes using mutant alleles initially described by Martin Heisenberg et al. more than 25 years ago. We characterized the different levels of associative conditioning and mushroom body defects seen in mushroom body miniature B (mbmB), small mushroom bodies (smu) and mushroom bodies reduced (mbr). This work has allowed us to implicate subsets of the MBs in different forms of associative conditioning. Surprisingly most of the mutants created in this screen have yet to be molecularly characterized. Extensive complementation analysis and sequencing revealed mbmB to be synonymous with the Drosophila Importin-2 (Imp-2). We present rescue experiments, western blot analysis, and have demonstrated that all Imp-2 domains are required for normal MB development. In Drosophila, imp-2 mediated nuclear transport is necessary for proper axon guidance, neuronal injury response, synaptic plasticity, cell proliferation and apoptosis, while its role in central brain development has not been investigated until now. This work provides a novel link between Importin--2 and MB development and offers insight on the cell biology of developmental and behavioral plasticity.



September

Date: Sep 02nd

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : ""Prior experience modulates a natural threshold for memory formation ""

Speaker: Kiriana Cowansage

Summary: Our current understanding of the molecular requirements for long–term memory come largely from studies that use experimental manipulations to alter average behavior. Few studies, on the other hand, have investigated the contribution of plasticity-related proteins, like CREB, to existing behavioral differences in memory strength that emerge naturally from genetically diverse populations. In this talk I will begin by presenting work from the labs of Joe LeDoux and Eric Klann (in collaboration with Sheena Josselyn) to identify rats from a normally distributed group that fail to form typical cued fear associations and express reduced baseline levels of phospho-CREB. Memory in this subset of rats was selectively improved by both pre-training exposure to contextual novelty and by virally mediated enhancement of amygdala CREB activity. These results provide some conceptual basis for current plans to investigate the cellular dynamics of weak versus strong associative memory traces in the lab of Mark Mayford, using a novel genetically encoded fluorescent timer expressed in mice under the control of neural activity.


Relevant Information:

Subach et al (2009) Nat. Chem Biol


Date: Sep 23rd

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : " 2½ Short Stories of Pavlov's Flies "

Speaker: Steven de Belle

Summary: Not provided


Date: Sep 30th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : " Talk 1: Grid cells, theta oscillations, and a novel code phase code of the head direction signal Talk 2: Septotemporal variation in theta rhythm dynamics "

Speaker: Mark Brandon and Jake Hinman

Summary: Not provided


Relevant Materials:

http://www.sciencemag.org/content/332/6029/595.full

http://jn.physiology.org/content/105/6/2675.full.pdf+html


October


Date: Oct 14th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : " AMPA receptor trafficking in reconsolidation of context fear memories "

Speaker: Tom O Dell

Summary: Not provided


Relevant Materials:

http://www.nature.com/neuro/journal/v14/n10/full/nn.2907.html



Date: Oct 28th

Time: 09:30 am

Place : 2nd Floor Conference Room, Gonda building.

Title : " Mental Schema and its Neural Correlates"

Speaker: Balaji

Summary: Not provided


Relevant Materials:

http://www.sciencemag.org/content/333/6044/891.full

November

Date: Nov 04th

Time: 09:00 am

Place : 1st Floor Conference Room, Gonda building.

Title : " The Cytoplasmic Fragile X Mental Retardation Protein1 CYFIP1 is a Key Player in Neurodevelopment: The Link with Autism"

Speaker: Claudia Bagni

Summary: Not provided

Previous Semesters

2011

Winter 2010

Fall 2010

Summer 2010

Spring 2010

Fall 2009