...home of ulrik r beierholm...
...home of ulrik r beierholm....
I am currently a post-dotoral researcher at California Institute of Technology,
working with Prof. Peter Bossaerts on Neuro Economics and decision making.
However I am about to move to London to take a position at the Gatsby at University College London, should be really exciting!
I got my PhD in May 2007 at Caltech, working with Prof. Steven Quartz and Ladan Shams on Bayesian modeling of perception, specifically multisensory.
I grew up in Copenhagen, Denmark, probably the coolest city in the world, and got my Bachelor of Science and Masters of Science (Physics) from the
University of Copenhagen where I studied at the Niels Bohr Instiute.
Interests include, but are not limited to, Computation, Neural encoding, Statistical models of decision making, Biological Diversity, Epistemology and Ontology, comic books, rock and electronic music as well as the rare imbibement of malt beverages.
Current Research
I am currently working on several projects studying human perception and decision making through Bayesian modeling.
One project with Steven Quartz and Ladan Shams at UCLA studies how humans combine information from several modalities.
The human nervous system is constantly bombarded by input from several senses. How does it decide to combine the information and how
does such a processing take place?
The example we are using is of the Ventriloquist Illusion. When a ventriloquist moves his puppet, we perceive the sound coming from the
puppet despite the fact that we know that the puppetmaster is generating the sound. The visual stimuli 'captures' the auditory stimuli
giving rise to the sensation of the sound coming from the puppet.
Using statistical models, such as Bayesian, we are trying to describe and test how such illusions arise in the central nervous system.
Another project, together with Cedric Anen and Peter Bossaerts at Caltech, involves modeling of human decision making and tracking the brain activity using functional MRI.
Subjects are asked to play simple games while being scanned in Caltech's 3 T Trio magnet, and we study correlations between their performance,
theoretical properties from Bayesian models and the BOLD signal from the scanner. This is still an ongoing project.
Talks
A hierarchical Bayesian ideal observer accounts for entire range of auditory-visual integration-segregation in humans
SFN 2006 .
The Ventriloquist Illusion as an Optimal Percept
Vision Sciences Society annual meeting 2005 .
Publications
Koerding K*, Beierholm U*, Ma WJ, Quartz S, Tenenbaum J & Shams L
Causal inference in multisensory perception.
PLOS ONE 9, e943 Aug 2007.
Shams L, Ma WJ , Beierholm U Sound-induced Flash illusion as an optimal percept.
NEUROREPORT 16 (17) 1923-1927 NOV 2005.PDF
Beierholm U, Nielsen CD, Ryge J, Alstrom P, Kiehn O Characterization of reliability of spike timing in spinal interneurons during oscillating inputs.
JOURNAL OF NEUROPHYSIOLOGY 86 (4): 1858-1868 OCT 2001 PDF
Alstrom P, Beierholm U, Nielsen CD, Ryge J, Kiehn O Reliability of neural encoding.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS 314 (1-4): 61-68 NOV 1 2002 PDF
Beierholm U, Jacobsen JCB, Alstrom P, Holstein-Rathlou NH
Characteristics of blood vessels forming ‘Sausages-on-a-String’ patterns during Hypertension
Accepted for publication in PHYSICA A.
Jacobsen JCB, Beierholm U, Mikkelsen R, Gustafsson F, Alstrom P, Holstein-Rathlou NH "Sausage-string" appearance of arteries and arterioles can be caused by an instability of the blood vessel wall.
AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY 283 (5): R1118-R1130 NOV 2002 PDF
Posters
Beierholm U, Quartz S, Shams L Bayesian inference as a unifying model of auditory-visual integration and segregation.
SFN 2005. PDF
Beierholm U, Quartz S, Shams L The Ventriloquist Illusion is Bayes-Optimal.
IMRF 2005. PDF
Beierholm U, Quartz S, Shams L Do within modality and cross-modality sensory integration follow the same rules?
Cosyne 2006.
Teaching
Nothing currently but I have been a teaching assistant for
CNS 186 Vision
CNS 187 Neural Computation
Projects
Master thesis
Rat project
A little guest appearence on page 27 of E & S no 2, 2002: PDF
Book of the moment:
Paul Glimchers "Decisions, Uncertainty, and the Brain: the Science
Of Neuroeconomics".
An interesting combination of description of classical neurophysiology and modern ideas about decision making.
CD of the moment:
Peeping Tom, "Peeping Tom", 2006.
Is it a bird? Is a plane? No, it is Mike Patton making pop music??? Well, almost.
Links:
ullers.dk A small diary I keep in danish.
Quartz lab
Ladan Shams
Wei Ji Ma
Contact
Ulrik Beierholm
Caltech MC 139-74
1200 E California Blvd
Pasadena, CA 91125
email : beierh at caltech . edu
