Recent Paper:  Neuroscience. 2002;115(4):1261-79

The amygdala has been implicated in processing information about the emotional significance of the environment and in the expression of emotions, through robust pathways with prefrontal, anterior temporal areas, and central autonomic structures. We investigated the anatomic organization and intersection of these pathways in the amygdala in rhesus monkeys with the aid of bidirectional, retrograde and anterograde tracers. Connections of the amygdala with orbitofrontal and medial prefrontal areas were robust and bidirectional, whereas connections with lateral prefrontal areas were sparse, unidirectional and ascending. Orbitofrontal axons terminated densely in a narrow band around the borders of the magnocellular basolateral nucleus, surrounded by projection neurons along a continuum through the nuclei of the basal complex. In contrast, the input and output zones of medial prefrontal areas were intermingled in the amygdala. Moreover, medial prefrontal axonal terminations were expansive, spreading into the parvicellular basolateral nucleus, which is robustly connected with hypothalamic autonomic structures, suggesting that they may influence the expressive emotional system of the amygdala. On the other hand, orbitofrontal axons heavily targeted the intercalated masses, which issue inhibitory projections to the central nucleus, at least in rats and cats. The central nucleus, in turn, issues a significant inhibitory projection to hypothalamic and brainstem autonomic structures. This evidence suggests that orbitofrontal areas exercise control on the internal processing of the amygdala. In addition, the results provided direct evidence that the connections of anterior temporal visual and auditory association cortices occupy overlapping territories with the orbitofrontal cortices particularly in the posterior half of the amygdala, and specifically within the intermediate sector of the basolateral nucleus and in the magnocellular part of the basomedial nucleus (also known as accessory basal), suggesting a closely linked triadic network. This intricate network may be recruited in cognitive tasks that are inextricably linked with emotional associations.

This seminar is co-sponsored by the Center for the Brain Basis of Cognition
 

November 17
11:00 - 12:00

Pharmacology
Library

Recent Paper:  Modulation of GABA_A Receptors by Hydrogen Ions Reveals Synaptic GABA Transient and a Crucial Role of the Desensitization Process

This seminar is co-sponsored by the Department of Pharmacology
 

12:00 - 1:30

Research Bldg.
Auditorium

Dr. Insel will also give an update on NIMH priorities

This seminar is co-sponsored by the Center for the Brain Basis of Cognition
 

January 13

12:30

Auditorium

Research Bldg.

Professor, Department of Human Genetics
University of Michigan
Dr. Meisler's website

"Sodium Channel Mutations in Epilepsy and Movement Disorders"

Recent Paper  "SCNM1, a putative RNA splicing factor that modifies disease severity in the mice. Science 301: 967-969, 2003"

Mutations in sodium and calcium channels produce a variety neurological disorders, including seizures, tremor, dystonia, ataxia, and paralysis. We identified mutations in the sodium channel gene SCN1A in families with an inherited epilepsy syndrome, GEFS+. To examine the pathological mechanisms, we are generating mouse models of the specific human mutations. In related projects, we are cloning several new mouse mutants, using new genomic tools including human/mouse genomic sequence comparisons to identify candidate genes and noncoding regulatory sequences.

Sponsored by the Department of Pharmacology

Friday

January 23

Warwick Evans

12:00

Senior Investigator
National Institute of Neurological Diseases and Stroke
Dr. Hallett's website

"Physiology of Free Will"

Dr. Hallett's research activities focus on the physiology of human voluntary movement and its pathophysiology in disordered voluntary movement and involuntary movement.

Sponsored by the Department of Neurology
 

February 10

Laboratory for Integrative Neuroscience
National Institute for Alcohol Abuse and Alcoholism
Dr. Lovinger's website

"Endocannabinoids are Retrograde Messengers Involved in Short- and Long-Term Synaptic Plasticity"

Recent Paper "Postsynaptic endocannabinoid release is critical to long-term depression in the striatum. Nature Neuroscience 5(5):446-451, 2002"

Dr. Lovinger's research interests include:

Interactions of intoxicating and general anesthetic agents with ligand-gated ion channels in mammalian neurons, and the contributions of such interactions to intoxication and anesthesia.

Characterization of the biophysical properties of 5-HT3 receptor-linked ion channels.

Synaptic transmission, modulation and plasticity in the striatum.

"How would you model autism in mice?"

Recent Paper "Central Galanin Administration Blocks Consolidation of Spatial Memory"

Laboratory on Behavioral Neuroscience investigates the behavioral actions of brain neurotransmitters, using rodent models of symptoms of neuropsychiatric diseases. Approaches include behavioral neuropharmacology and behavioral genetics.

       Galanin is a neuropeptide that acts as an inhibitory modulator of acetylcholine and glutamate pathways relevant to learning and memory. We found that galanin induces delay-dependent working memory deficits on T-maze delayed alternation and operant delayed nonmatching to position, prevents selective quadrant search in the Morris water task, impairs consolidation via a forskolin-reversible mechanism, and inhibits acetylcholine release from the septohippocampal pathway. Galanin is overexpressed in the basal forebrain in Alzheimer’s disease, while other neurotransmitters are declining, suggesting a unique role for galanin in this disease. We are now evaluating galanin receptor antagonists in cognitive paradigms, to test the hypothesis that blocking excess endogenous galanin may help alleviate the memory deficits characteristic of Alzheimer’s disease.

       Transgenic knockout mice with mutations in genes expressed in the brain, provide powerful new tools for understanding the genetic substrates of behavior. Using a wide variety of relevant behavioral paradigms, our laboratory developed a strategy for behavioral phenotyping that is becoming widely used. Galanin overexpressing transgenic mice are normal on measures of general health, neurological reflexes, sensory abilities, and motor functions, but show selective deficits on the Morris water maze probe trial, trace cued fear conditioning, and social transmission of food preference. Several fascinating new targeted gene mutations are presently being phenotyped, including galanin receptor GAL-R1 knockout mice and serotonin transporter knockouts. Social behaviors and cognitive flexibility are being evaluated in mouse models relevant to autism. DNA microarray analyses of behaviorally tested rats and mice are designed to discover genes mediating cognitive processes and social behaviors.

March 16

Department of Pharmacology and Molecular Sciences
   and Department of Neuroscience
The Johns Hopkins School of Medicine
schnaar@jhu.edu
Dr. Schnaar's homepage

"Axon regeneration inhibitors - Receptors and ligands limiting
recovery from CNS injury"

Recent paper:  "Gangliosides are functional nerve cell ligands for myelin-associated glycoprotein (MAG), an inhibitor of nerve regeneration"  

Dr. Schnaar's laboratory explores the molecular mechanisms neural cells use to communicate with each other when they come into contact. This type of communication, also called Cell-Cell Recognition, is important to nervous system development, and the maintenance of proper intercellular contacts in the adult brain.
 

March 23

Margaret M. McCarthy, Ph.D.

Department of Physiology
Director of Graduate Education,
Program in Neuroscience
University of Maryland
mmccarth@umaryland.edu
Dr. McCarthy's homepage

"Stacking the Building Blocks of the Male Brain"

Recent paper "A Novel Mechanism of Dendritic Spine Plasticity Involving Estradiol Induction of Prostaglandin-E2"

Dr. McCarthy's research program focuses on the influence of steroid hormones on the developing brain. During perinatal life, there is a sensitive period for hormone exposure during which permanent cytoarchitechtural changes are established. Males and females are exposed to different hormonal milieus and this results in sex differences in the brain. These differences include alterations in the volumes of particular brain nuclei and patterns of synaptic connectivity. The mechanisms by which sexually dimorphic structures are formed in the brain remains poorly understood.

March 30

"Amphetamine's neurotoxicity: Bridging drugs of abuse and neurodegenerative disorders"

Recent paper "Methamphetamine produces neuronal inclusions in the nigrostriatal system and in PC12 cells"

Recent paper "A Comparison of Primate Prefrontal and Inferior Temporal Cortices during Visual Categorization.  J. Neurosci. 23: 5235, 2003"

Previous studies have suggested that both the prefrontal cortex (PFC) and inferior temporal cortex (ITC) are involved in high-level visual processing and categorization, but their respective roles are not known. To address this, we trained monkeys to categorize a continuous set of visual stimuli into two categories, "cats" and "dogs." The stimuli were parametrically generated using a computer graphics morphing system (Sheltonelton, 2000) that allowed precise control over stimulus shape. After training, we recorded neural activity from the PFC and the ITC of monkeys while they performed a category-matching task. We found that the PFC and the ITC play distinct roles in category-based behaviors: the ITC seems more involved in the analysis of currently viewed shapes, whereas the PFC showed stronger category signals, memory effects, and a greater tendency to encode information in terms of its behavioral meaning.

This seminar is co-sponsored by the Center for the Brain Basis of Cognition

April 13

Nathan E. Crone, M.D.

Department of Neurology 
Johns Hopkins University
ncrone@jhmi.edu
Dr. Crone's website
        
"Human Brain Mapping with Electrocorticography"

Intracranial Electrophysiological Recordings in Humans and Their Relation to 
Cognitive Functions and Epilepsy"Dr.Crone's laboratory is developing 
electrocorticographic (ECoG) spectral analysis as a method for mapping brain 
function in real time, in order to minimize functional deficits during brain surgery 
for epilepsy. These methods are also being applied to electroencephalographic (EEG) 
recordings in normal subjects so that they may be used to noninvasively study the 
brain mechanisms of human language and other higher cognitive functions. 
        

Harvard University
Faculty of Neuroscience
benesf@mclean.harvard.edu

"GABA Neurons in Schizophrenia and Bipolar Disorders"

Recent paper "Amygdalo-cortical sprouting continues into early adulthood:  Implications for the development of normal and abnormal function during adolescence.  J. Comp. Neurol. 453: 116, 2002."

The Brain Collector

From her website:
Francine Benes is both a cellular neuroanatomist and a psychiatrist investigating how the brain may be miswired in schizophrenia and other neuropsychiatric disorders. Although she started her career studying simple systems such as peripheral nerve and frog neuromuscular junction, she now uses neuroscientific techniques to identify how neural circuitry in the cerebral cortex is altered in postmortem brains of patients with schizophrenia. An important corollary issue that her laboratory is exploring is how normal brain development may help to trigger the typical onset of schizophrenia during late adolescence and early adulthood. Toward this end, studies of brain maturation in human postmortem material, as well as in rodents, are being used to define the precise ways in which normal ontogeny may interact with the risk factors for schizophrenia and produce the altered neural circuitry being identified in this disorder. Her studies have been directly influenced by the knowledge she has gained from treating patients with schizophrenia and other psychiatric disorders. Benes has published many original research articles in distinguished neuroscience and psychiatric journals. She is an expert in neuroscience, psychiatry, and developmental psychopathology.
 

Auditorium

Research Building

"Studies of Perception, Memory, and Metacognition in Rhesus Monkeys"

Journal club in W202 Research Bldg 9:00-10:00

10:00 am

NE201C

Recent Paper "Delayed Rectifier K+ currents, IK are Encoded by Kv2 a-Subunits and Regulate Tonic Firing in Mammalian Sympathetic Neurons"

From her website:
Ongoing research in this laboratory is focused on delineating the mechanisms involved in the regulation and modulation of voltage-gated ion channels in cardiac myocytes and cortical neurons. In the myocardium, our interest is in the Ca++- independent depolarization-activated K⁺ channels that determine the heights and the durations of cardiac action potentials. In addition to examining the electrophysiological properties of these channels, we are exploring the molecular basis of the functional diversity of K⁺ channels found in cardiac cells and the molecualr mechanisms controlling the regulation of functional K⁺ channel expression in the normal as well as the diseased heart. In addition, we are exploiting dominant negative and targeted deletion strategies to effect the functional knockout of K⁺ channels in the mouse heart and examining the physiological and pathophysiological consequences of these maniplations. 

May 11

Head, Cellular and Molecular Biology Division
Toronto Western Research Institute
Tanenbaum Chair in Molecular Neuroscience

"Transmitter Release Site:  A Cannon or a Catapult?"

Recent Paper:  "Single calcium channels and acetylcholine release at a presynaptic nerve terminal"  Neuron 11: 1007, 1993  (classic paper - In the Library)

Research Area:  Understanding information processing in the brain which is necessary for sensation, muscle movement, memory, learning and thought

Dr. Stanley's website

May 18

Special Neurolunch
NE201 C

Graduate Student, IPN
         
“Regulation of DNA Repair Following Seizures”

Thesis Defense Seminar  - Warwick Evans Room -  Bldg D 9:00 am

Graduate Student, IPN

"Phonological Processing Studied with Functional MRI"