Based on a true story – how progress is made in the field of adult neurogenesis* A group of scientists reduce neurogenesis and report a memory deficit. A second group repeats the experiment, with only a few minor differences in protocol, and fails to find a memory deficit. A third…
And here we have the latest, craziest hypothesis of granule cell function. Crazy not because the authors have lost their minds but because the story of the dentate gyrus, where adult neurogenesis occurs, is becoming more peculiar every day. The underlying premise of this paper by Alme et al. (which we…
And now for a journey outside (rostral, to be precise) of my comfort zone. These three pictures show new neurons in the mouse olfactory bulb at successively greater magnifications. Probably inspired by the science magazine I read as a kid that would show high mag photos of everyday objects (with corresponding…
I was recently reading a number of old papers on memory and synaptic tagging and found myself wondering whether they were bloggable. My instincts said yes but the more I thought about it the more I realized they’re several years old and that is ancient by the standards of Twitter…
It’s fun to zoom out and get the big picture sometimes. This is one such picture I took long ago when I wanted to see if staining for zinc transporter 3 effectively labels the mossy fiber axons of the dentate gyrus. You can see by the perfect overlap with calbindin…
A fundamental property of the hippocampus is its ability to rapidly encode memories while simultaneously keeping them distinct. Recording from hippocampal neurons one can clearly see that different populations of neurons are active as a rat explores two environments. This is thought to be one mechanism by which information is…
Dendrites are the extensions of neurons that receive incoming information. Neurons have primary dendrites that further split off into secondary and tertiary dendritic branches. On each of these branches are thousands of synaptic connections with axons of neurons carrying incoming information. The result is a dendritic tree that is capable of receiving…
Yesterday I was taking pictures of 1-day-old neurons, which was irritating me for several reasons. First, at this age they’re small, irregular and uglier than the mature neurons I’m used to examining. Second, very immature neurons are located amongst a mess of proliferating cells and fellow young neurons so it…
Two recent papers have attracted a lot of media attention because they draw direct links between adult neurogenesis and behavioral disorders: Noonan et al. showed that rats lacking adult neurogenesis (stopped with irradiation) are more susceptible to cocaine addiction. Jin et al. showed that mice lacking adult neurogenesis (using a…
I recently became re-acquainted with the neurogenesis literature while writing the last post, re-finding data in papers whose gist, but not details, I had remembered. I reached out a little bit, asking others if I had forgot any studies and indeed I had, including this study by Okano, Pfaff and…
Most studies of adult neurogenesis are concerned with neuronal age. Or at least they should be. This is because new neurons develop from a stage where they have no excitatory synapses to one where they have many. If we assume the traditional view that information is stored at excitatory synaptic…
Studies of adult neurogenesis often begin with the following sentence: “Adult neurogenesis occurs in all mammals examined, including humans.” More detail-oriented papers might say, “Adult neurogenesis occurs in all mammals examined, including humans…but not bats.” Here, the similarities between bats and humans become more evident than one might expect: it…
At 0.6% of the way into the decade, we’re well beyond the timeframe when most “things of the decade” articles appear. Now that “decade hype” has settled down I thought it would be fun to write a series of posts that discuss some of the major themes in adult neurogenesis…
The list as a Google spreadsheet (also excel | HTML | RSS feed of updates) List last updated 3/9/2011. I’ve always enjoyed making lists. As a kid I can remember writing lists of rhyming words, lists of all the Ocean Pacific clothes I owned, lists of all the people I knew.…
Kitamura et al. (2009) Adult Neurogenesis Modulates the Hippocampus-Dependent Period of Associative Fear Memory. Cell. 139:814-827. It’s great to see this paper finally in print. At SFN 2008 the authors had a poster that generated a lot of excitement, at least in our circles. And the poster was quite a…