VS131 VISUAL NEUROSCIENCE

Timothy Gawne, VS131 Coursemaster Worrell Bldg, Rm. 664 (Office) 235/236 (Lab) Office Phone: Lab Phone: Lectures: Monday, Tuesday, Wednesday AM. Grading: Four equally-weighted exams. THE EXAMS ARE CUMULATIVE. Your grade is the highest of the average of the four exams, or the final by itself. No assigned text, all handouts.

So what is the visual system anyhow? -> Optical System -> Phototransduction (rods and cones) -> Computation ***** Largest part by far ***** Something like 1/3 to ½ of the brain required for our full visual capability.

Basic Anatomy

More brain Anatomy.

More brain Anatomy.

So how does the visual system work? -> Don’t really know! But learning fast – this course will be on what we have discovered so far, and as you will duly realize, it’s quite a lot. -> One of the most fundamental and exciting problems in modern science -> Ultimately bears on the issue of what is the mind, and what is consciousness. -> But for now, robots that ‘see’ are still very much science fiction. A video camera can RECORD an image, but it can not understand what it means and is thus perceptually blind…

Science fiction robots! Not there yet…

More science fiction robots…

(But perhaps some things are best left undone) (Roll film)

In the last 30 years computer science has taught us biologists something very important: 1.Tasks that are fundamentally EASY include playing chess at the master level, solving calculus problems, and factoring prime numbers. 2.Tasks that are fundamentally HARD include recognizing objects by looking at them, walking, playing with LEGO blocks, and ‘common sense’. 3.Category 1 only seems hard because it’s not what our nervous systems are well adapted for.

Problem: write a computer program to take an array of numbers that represent a 2D pattern of light on a retina, and have the program figure out if there is a teapot in the external scene. Nobody knows how to do this just yet …

The fallacy of the homunculus!

VS131 Course Overview: -> The Neural Retina -> Retinal Recipient Nuclei -> Visual Cortex (the ~95% of the visual system that is not in the eye!) -> Development (normal and abnormal) -> Clinical Applications: -> Visual Correlates of Central (Brain) Problems -> Interpreting an Electroretinogram -> Interpreting a Visual Evoked Potential (VEP)

VS131 Course Goals: -> Pass the boards -> Get the basic knowledge required for a professional working with vision: the groundwork for future teaching, research, changes in the field of optometry -> Intellectual foundation for differential diagnosis: especially visual problems not in the eyeball. -> Background for ordering and interpreting clinical tests including the electroretinogram (ERG) and cortical visual evoked potential (VEP).