Mark Dow

 Mark's gradient at skin surface skin surface unwrapped Brodmann labelled brain human brain, rendered from Colin27T1, link to axial MRI slices of various contrasts, link to axial MRI slices of various contrasts, link to axial MRI slices of various contrasts, link to axial MRI slices of various contrasts, link to axial MRI slices of various contrasts, link to  Pell spirals similarity tiling link Brigid's cross tilings, link to Thue-Morse sequence tiling link Thue-Morse cube, link to Logarithmic spirals, waves and tilings, link to Three symbol symmetric systems with two terminating rules, link to

Research Assistant
Brain Development Lab, University of Oregon

e-mail: dow[at]uoregon.edu
*cell*954-6780**

Visual system mapping
Geek art, geometric images and algorithms
Space Software, volumetric data manipulation and visualization
Scale Space Edges software, Matlab edge detection
My BDL and LCNI stuff, publications, presentations, etc.
My other stuff, some of
Other people's great stuff

Visual system mapping

    I work on software for image and functional MRI time series analysis, and currently am involved with fMRI projects involving retinotopy and visual spatial attention.

Segmentation software tools for neuroimaging

    These include 3-D surface extraction and segmentation algorithms, and volume navigation and editing tools that provide a framework for semi-automatic region of interest generation and landmark specification. The approach we are developing is based on edge/surface detection using Gaussian derivative filters, over-segmentation, and hierarchical region combination. The goal is to quickly identify primary surfaces, landmarks, and other image based features, and to use maps of these features to inform segmentation or parcellation of 3-D images.

Far peripheral human vision

    These fMRI experiments are designed to investigate the organization, operation, and plasticity of cortical areas involved in visual processing at large (20-80 degree) eccentricities. We use light guiding fibers to present flashing stimuli at peripheral locations during functional imaging. Retinotopically mapped visual areas and areas that preferentially respond to peripheral visual stimulation are identified. We are investigating the extent and organization of these visual areas, and how they are modulated by spatial attention. Comparison of hearing and congenitally deaf adults results will elucidate how visual cortical networks are modified and modulated by profoundly different auditory experience.
    These studies are done in collaboration with Greg Scott and James Dugan.

Geek art, geometric images and the algorithms that generate them

My deviantArt gallery
I, phone, link to Sodium cherry, link to
Space Software example volume and slice renderings
Quail chick rendered from MRI, link to Quail and human visual hardware, link to Four knot 1, link to virion structure rendering, link to
Space Software example animations
Human brain, blended Brodmann area coloring, link to Virion_structure_animations, link to
About Mark's fractal geek art
Simple recursive systems and fractal patterns
Pell spirals tesselation link Bar rotation similarity motifs squeel tesselations link Brain Frieze
Thue-Morse sequence tilings
Thue-Morse sequence tiling link Thue-Morse cube, link to Three bars motifs, link to Thue-Morse mesh tiling Thue-Morse X tiling, link to Thue-Morse diag1 tiling, link to Thue-Morse dual twist tiling, link to Thue-Morse half-diagonal tiling, link to Thue-Morse half-diagonal shaded tiling, link to
Squeel tessellations
2x2 4-rotation cyclic L-systems
2x2 symmetric L-systems
 Three symbol symmetric systems with two terminating rules, link to Five symbol symmetric systems with two terminating rules, link to Five symbol symmetric systems with two terminating rules, link to Five symbol symmetric systems with two terminating rules, link to Seven symbol symmetric systems with two terminating rules, link to Square wave quarter-twist system, link to Square waves system, link to 

Brigid's cross tessellations
Brigid's octomino Thue-Morse tesselations link Brigid's cross similarity tilings, link to Brigid's cross similarity tiling thumbnail Brigid's pyramids articulated thumbnail Brigid's pyramid spiral face thumbnail
Pell spirals
Oak cubes and hexagonal tilings
Binary fractal images
Mobius bands and tilings
Logarithmic spirals, waves and tilings

Logarithmic spirals, waves and tilings, link to Orthologia, link to

Directional edge contrast motion illusion comparison   
Minimal arrays containing all sub-array combinations of symbols
miscellaneous MRI related images
brain art fodder


Space software

MRI Space software animation Free volume navigation, visualization, and editing software (MS Windows). In active development, in collaboration with Greg Scott.

        Space software download, description, and examples
        program description
        example volumes
        animation examples
        rendered image example


Scale Space Edges software

eye edges, SS_Edges

Matlab tools for 2-D edge extraction and segmentation.

        Scale Space Edges download, description, code, and examples


My BDL and Lewis Center for Neuroimaging stuff

  Publications:
 Scott, G., Dow, M., Neville, H. J. (2003). Human retinotopic mapping of the far periphery. Society for Neuroscience 2003 poster. [.pdf ]
 Dow, M., Nunnally, R. (2004). An edge based image segmentation method. ISMRM 2004 poster. [abstract .doc , poster .pdf ]

  Reports:
Dow, M., Dow, A. (2003). Measuring the earth's shape: Maximum solar elevation observations, through space and time. [ .ppt (13 MB)] [print/high res. version:  .ppt (32 MB)]
Dow, M. (2005). LCNI science meeting 2/9/05: BOLD localization of short visual events. [.ppt (8 MB)]

  miscellaneous, BDL and LCNI:
Psych 607 class resources , winter 2004
LCNI resources
LCNI historical
MATLAB class, summer 2008

Some of my other stuff

Other projects

Programmers Anonymous, an informal programming class I lead
Thermodynamic entropy and information, their relationship as I understand it
Dense Image Space, photographic/software project, in process

Miscellaneous

Internet Black Hole Discovered, computer fiction science journalism (inspired by Sean Michael Ragan's fiction science)
0-bit for Brie, a laptop's obituary
   

 Family and friends

Wayne Dow's web site, my dad's personal, family and family history material
pics, Yoshiko's party 6/06
Tonn Nua, the group my son Ansel makes music with
Tonn Nua, link to
pics, Kristen and Jasper-Jon's wedding
Kristen and Jasper's wedding, link to

Other people's great stuff 

The Geometry Junkyard
Sean Michael Ragan, great ideas
Enzymind, Peter's online Laboratory (currently in development). I blog occasionally on this site (mwd).
deviantART, great art, searchable. Here are a few of my favorites.
Mathematical imagery, Jos Leys
The Brain From Top To Bottom, tour of human brain functional neuroanatomy
fMRI 4 Newbies, tutorials
Tatjana van Vark's instuments, particularly her The Harmonium for mechanical Fourier analysis and synthesis
Making Art the Otto Lange Way (I recommend subscribing to the blog through email)

Some great free software

World Wind, virtual spherical navigation
MRIcro, Chris Rorden's free, great volume display software
IrfanView,  Irfan Skiljan's free, great 2-D image software
Nvu, free, great web page generation, web authoring software
MRIcro, Chris Rorden's free, great volume display software
Google Desktop, hard drive indexed search
MRIConvert, Jolinda Smith's free, great GUI batch DICOM file conversion program