May 7, 2019, Andre Fenton and I interview Jim Ranck. The interview is quite long — 90 minutes — and is organized in a decade-by-decade manner. For each segment we discuss Jim’s personal history, his scientific accomplishments, and some major events in Neuroscience.
watch, above, or go directly to youtube: https://youtu.be/i6hIVqXPNdQ
The interview contains lots of hippocampal minutia. Best suited for people in the field … but I think there are other gems.
The timeline is something like this:
0:00:00 1930-40s birth thru college:
0:04:50 1950s med school, Univ chicago, Public Health
0:20:10 1960s Univ Washington, Biophysics, Brain Impedance, Mich
0:31:00 1970s Hippocampal Neurons, O'Keefe & Nadel
Phil Best, place cells are real
0:48:00 1975 Move to Brooklyn, single neurons
1:08:43 1980s (part 1) computerized data collection and
1:10:40 1980s (part 2) Head-Direction cells. Ego and allocentric
1:22:55 1990s Cognitive Neuroscience, the book.
Most important segment is on discovery and description of Head-Direction Cells,
1:10:40 – 1:23:00
The function of learning is clear: modifying behavior through experience. Memory, the storage of information that supports learning, is clearly necessary and valuable. Current psychology and neuroscience tell us that there are two memory systems enabled by separate neural systems. Procedural memory relies on reward circuitry and trial-and-error processes to mold efficient behaviors. Episodic memory stores specifc events in the life of the individual — but for what purpose? Continue reading
My post on the brainfacts blog, “Let’s stop using the term “Hard Wired“. Intended to get people to think more carefully and avoid sloppy metaphors.
In 1981 I was an eager post-doctoral fellow, learning to record place cell’s in Jim Ranck’s lab and beginning to understand John O’Keefe and Lynn Nadel’s “Cognitive Map” theory of the hippocampus. One afternoon, while I had a rat in the maze and watched traces of action potentials sweep by on the oscilloscope, Jim Ranck looked over my should and said …
“This is terrific! Place cells are the gateway to understanding how the brain produces cognition.”1
This was both inspirational and opaque. Continue reading
Years ago, when my daughter was 6, her friend Daisy1 proudly announced,
“I still believe in Santa Claus. I think I’ll believe in Santa one more year.”
There are several amazing things in this statement. Continue reading
I’ve made a posting on the BrainsFacts Blog site on Grid Cells and Path Integration. Aimed at High School and College students, but I think it gets complicated. Write your comments here!
Also, planning a third post or the Modular organization of Grid Cells. Based on new paper “Specific evidence of low-dimensional continuous attractor dynamics in grid cells” (Yoon et al) published in Nature Neuroscience.
Three years ago the New England Journal of Medicine published a remarkable case study : “Cycling for Freezing Gait”. The report from doctors in the Netherlands describes a man with severe Parkinson’s disease who was virtually unable to walk, but, when put on a bike, rode beautifully, including the ability to turn, raise off the seat for power, and comfortably dismount.
Yesterday evening Deron Williams drained 8-straight 3-point shots at the start of the Brooklyn Nets’ win against the Washinton Wizzards (Nets, my team!). He was ‘hot’. He was on a streak. He was in rhythm. As Deron said, at the end of the streak, “yeah, I was on a heat check”.
Was it a real streak? Was he hot? In synch? If there are streaks, what does that say about human athletic performance and neuroscience?
Stephen Gould addressed the question* of whether there are streaks in athletic performance 25 years ago in a lovely article in the NY Review of books (1988). Interestingly, Gould focused on two types of streaks: streak shooting in basketball, and Joe Dimaggio’s 56-game hitting streak. He summarized then current work by Arvin Tversky and Ed Purcell, using fairly simple probability techniques. Conclusion: from NBA shot statistics were there no evidence of “hot streaks” or “hot hands” in basketball; but the DiMaggio’s streak was truly unusual. I don’t have ready access to the background work (correction: Golovich et al, 1985**), nor more recent analysis, but I did a back-of-the envelope calculation this morning.
My calculations: Continue reading
(Updated with comparison to Mankin et al Feb 20; in red text)
“Long-term dynamics of CA1 Hippocampal Place Codes” is an important study published in the current issue of Nature Neuroscience. The paper is noteworthy in terms of technical achievement, theoretical implications and the potential for future work
Headstage on mouse brain. Ziv et al fig 1a.
First, the technical achievement. Ziv et al, working in Mark Schnitzer’s group at Stanford have managed to record the firing activity of hundreds of hippocampal neurons over a period of approximately one month. They do this by permanently mounting a miniature camera on the mouse’s head and using Ca+ imaging to identify the firing pattern of each neuron. Continue reading
The term “egocentric” has nothing to do with Freud or selfishness. It’s a geometric term meaning that part of the self is the center of the spatial coordinate frame (“ego” = self). The contrasting term, “allocentric” means something other than the self is the center of the coordinate frame (“allo”= other). A comparison has helped me: think of geocentric and heliocentric models of the solar system.
The question I’m going to address is whether our brains, our perception of the world, our behavior, and our consciousness operate in egocentric or allocentric coordinate frames.