PNP/Medical School Lunchtime Seminar: 12:30 pm, Medical School Campus*
*2nd Floor Lrg. Conference Rm., (2311), East Building, 4525 Scott Avenue

(In progress, will be updated upon receipt of information)

Current/Future

Sept. 9		TBA
Oct. 14		TBA
Nov. 11		Deanna Barch, Psychology
Dec. 9		TBA

Past Spring 2009

Jan. 21		Stanley Finger, Washington University Abstract: The medical usage of electric fish deserves more attention than it has been given. The Romans, who discovered electric fish therapy by accident, first used live torpedoes (saltwater rays) for treating headaches and the symptoms of gout. Reference to live fish cures can also be found in Arabic texts prior to the European Renaissance. During the second half of the 18th century, when electricity came into vogue, South American electric "eels" were used to treat paralyses and other disorders, much like medicinal Leyden jars. These clinical trials led to the revolutionary idea that a few living creatures might be electrical --- a notion that Galvani would subsequently extended to the neuro-muscular system of other organisms, including people. Historically, the death of nerve spirits and the birth of modern electrical neurophysiology began with fish, not frogs.
Feb. 11		Steve Small, University of Chicago Context, Language, Action, and the Brain: Revisiting the Milieux Intérieur and Extérieur Abstract: The milieu extérieur and the milieu intérieur of Claude Bernard have a modern relevance to research in brain imaging. In particular, we interpret these as analogous to ecological context (the external environment), on one hand, and neural context (neuronal interactions) on the other. In this talk, we discuss the roles of ecological and neural context in the investigation of the neurobiology of human language. People understand language quickly and effortlessly, an experience that reflects the operation of powerful adaptive mechanisms that work to reduce the degrees of uncertainty during processing of an incoming speech signal. Visual observation of the speaker, particular the motor behaviors of the speaker, represents one set of important disambiguating factors for understanding speech and language. Consistent with existing behavioral research, we have proposed that action observation by listeners, specifically observable speech-associated mouth movements and hand gestures, plays a critical role in this process. The neural mechanism by which this occurs cannot be characterized by localizational neurology or modular psychology, but instead requires analysis of population codes and regional interactions. This talk will discuss these conceptual issues in the course of presenting several experiments that aim to understand the brain mechanisms involved in using observable actions to decrease ambiguity during face-to-face language comprehension.
March 18		Erik Herzog, Washington University "The politics of periodicity: A network of circadian pacemakers in the brain."

Past (Fall 2008)

Sept. 10

Randy Larsen, William R. Stuckenberg Professor of Human Values and Moral Development and Chair, Psychology
"Automatic vigilance for threatening information: Misperceiving weapons and other dangerous objects"
Priming techniques can be used to investigate a number of cognitive processes. Examples of racial priming will be discussed, and re-interpreted as being due to the activation of affective factors rather than solely relying on the activation of racial categories. Results of several experiments will provide evidence that affective information can bias responses to a number of stimulus categories. Other techniques for investigating the roll of affect in the cognitive system will be reviewed, e.g., perceptual search paradigms, attentional capture paradigms, and emotional Stroop-like paradigms. An ongoing research program using these paradigms to study age differences in emotional cognition will be introduced.

Oct. 15

William Thomas Thach, M.D., Professor of Anatomy and Neurobiology, Neurology
"Changing roles of the Basal Ganglia and the Cerebellum in the control of Posture and Movement"
Because the basal ganglia project to certain brainstem nuclei concerned with bodily posture, and because basal ganglia disease in humans causes fixed postures (e.g., Parkinson’s Disease), they had been designated posture generators (Denny-Brown). When the basal ganglia were then shown to project as well to the thalamus and thence to cerebral cortex (Mehler), and since their disease in humans may cause involuntary movements (e.g., Huntington’s Chorea), they were then also designated generators and initiators of movement (Denny-Brown). Because the cerebellum was thought at the time to receive mainly or only afferent information from sensory receptors via the spinal cord, it was presumed to modify movement (depending on movement feedback) only after movement initiation (Sherrington, Ruch). Newer information. 1) Timing: basal ganglia output neurons fire only after muscle activation and movement onset. By contrast, the cerebellar output precedes both muscle activation and movement onset and even the earliest changes in motor cortex (to which it projects via thalamus) (Anderson , Mink). Damage of the cerebellum delays both motor cortex activation and movement onset (Brooks and colleagues). 2) Output coding: the output of the basal ganglia is inhibitory (GABA) to all targets (Penney and Young); the output of the cerebellum is excitatory to all targets (Eccles, Ito, Sasaki). These results lead to the following formulations: The cerebellum acts to generate an initiate compound movements comprising many muscles and joints. Simpler movement components are not similarly cerebellar controlled: cerebellar lesions cause incoordination of compound movements with relative sparing of simpler movements (Babinski). The cerebellum also is key in learning novel compound movements (Marr, Albus, Ito, Gilbert, Thach, Thompson). By contrast, the basal ganglia act upon movement generators in other parts of the motor system either to inhibit those many possible movements we don’t want to make, and to disinhibit those movements that we select to make (Hikosaka and Wurtz, Mink)—after movement has already begun. Basal ganglia lesions release these many potential movement and posture generators to compete, causing rigidity and involuntary movements. Questions of great current interest: Do both play roles in motor learning? In cognition and affect?

Nov. 12

Timothy Holy, Assistant Professor, Anatomy and Neurobiology
"The nature of mammalian communication signals: songs and smells"

Abstract:
Mice and other mammals communicate socially using signals detected by several different sensory modalities. In this talk I will describe our in-depth characterization of two of these classes of signals: the ultrasonic songs of male mice, and the chemical signals (sometimes called pheromones) detected by the accessory olfactory system.

Dec. 10

Abraham Z. Snyder, Ph.D., M.D.
Departments of Radiology and Neurology
Title: 'On the mind-body problem ("consciousness")'

Past (Spring 2008)

Jan. 16

Todd Braver, Psychology
"Neural mechanisms of higher cognition: Anterior prefrontal cortex
and goal-subgoal coordination"

Feb. 27

Carl Craver, PNP Program
"Laws and Explanation in Neuroscience"

March 19

Kurt Thoroughman, Biomedical Engineering; Anatomy & Neurobiology
"Neural Computation and Human Motor Behavior"

April 9

Larry Snyder, Anatomy & Neurobiology
Title: TBA

May 14

Steven Small, Neurology & Psychology, Chicago
Title: TBA

Past

Sept. 12, 2007

Joseph Price, Anatomy & Neurobiology
"Differential Subregion and connectional circuits within the prefontal cortex"

Oct. 10, 2007

Jason Hill MD/PhD student (Dr. Jeffrey Neil's lab), Dept. Neurology, Pediatrics, & Radiology, Washington University in St Louis (Medical School Campus)
"Baby Brains: A surface based approach to studying cortical development in neonates. "

Nov. 14, 2007

Ian Dobbins, Psychology
"Lateral prefrontal cortex and strategic memory retrieval"

Dec. 12, 2007

Charles Anderson, Anatomy & Neurobiology; Physics
"The Brain is an Analog Computer" (*subject may change)