Athletic Streaks and Neuroscience

deron williams jumpYesterday 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

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Optical Recording of Maps in the Hippocampus

(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

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

Are Brains Egocentric?

Hippocampal Representations

Hippocampal Representations
egocentric? allocentric?

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.

Continue reading

Features of Consciousness

midsagFeature lists:

List 1: “essential consciousness (level 1)”. I suggest these are the core features of consciousness, common to all conscious creatures on planet earth.

List 2 : “Level 2 consciousness”. Level 2 consciousness is a higher consciousness, present in most humans and, likely some other mammals. Level 2 is qualitatively different from level 1 and some consider it to be true “conscious”. I’ve taken the approach of distinguishing two levels. My dogs are conscious, but not level 2.

List 3: “Biological Features Connected to Consciousness” A speculative list of behavioral and structural features whose evolution may be tied to consciousness.

Continue reading

Does a thermostat have consciousness?

 

(the following is a short piece I wrote two years ago in a private blog. I’m making it public and reposting because of similarities to arguments in John Searle’s review of Chistof Koch’s book in the NYRB. I found Searle’s review excellent. Unfortunately, most is behind NYRB firewall)

David Chalmers proposes that consciousness is inherent in informational structures1,2. As a reductionist example, he suggests that a computer, which organizes large quantities of information, or a thermostat, which organizes much smaller quantities, has a measure of consciousness. Some physicists (Penrose, Wheeler) have proposed that when natural phenomena are better understood, ‘information’ (non-random organization) will be recognized as a principal feature. Continue reading

David Marr was brilliant, but wrong

David Marr was a brilliant Neuroscientist who died too young, in 1980, at the age of 35. Marr’s work was theoretical — he was at the leading edge of a computational wave.* Marr’s contributions spanned many areas of Neuroscience: cerebellum, hippocampus, and especially vision. Marr is also well known for proposing that brain/behavior function should be approached in three phases that are largely sequential:

  1. The computational level: what is the problem that confronts the animal?
  2. The algorithmic level: How is it logically solved? (including shortcuts)
  3. The implementation level: How does the brain do it?

Continue reading

Hypothalamic Rage

rage ratA year ago Dayu Lin and co-authors published a landmark study in Nature on the hypothalamic nucleus which, when optically stimulated, produces undifferentiated rage. At that time Ed Yong wrote a wonderful summary of the work.

The point: in the mouse there is a region in the hypothalamus which, when stimulated, produces undifferentiated rage. There is reason to believe there is an equivalent region in humans. While we don’t go around with optogenetic probes in our brains, the state of undifferentiated rage is not uncommon. Many of us have experienced times when rage is out of control — difficult to keep in check by reason or logic. This is why I don’t like having guns within easy reach.