More Being Learned About Memory, Neuron by Neuron

Psychiatric News   |   June 01, 2012

Volume 47 Number 11 page 24a-24a

Clinical and Research News

Aaron Levin

Infusing a single neuron with a transcription factor can make a memory, and a bit of diphtheria toxin can take it away. …

Yet more recent work finds that single, specific neurons in the human hippocampus are indeed part of a memory trace, said Sheena Josselyn, Ph.D., a senior scientist in neurosciences and mental health at the Hospital for Sick Children in Toronto and an associate professor of physiology at the University of Toronto. …

…a 2008 report by Hagar Gelbard-Sagiv, Ph.D., …“the activity of single neurons in the human hippocampus and surrounding areas when subjects first view cinematic episodes consisting of audiovisual sequences and again later when they freely recall these episodes.”

Among the test sequences was the often-shown clip of Tom Cruise jumping up and down on Oprah Winfrey’s couch.

“That single neuron fired only when viewing the Tom Cruise video or when remembering it, but not at other times,” said Josselyn. …

Next she used diphtheria toxin to kill only the cells previously infected with the viral CREB. …

However, killing neurons to eliminate memories was an extreme step, so Josselyn sought to block the action of the affected cells in some less drastic way. …

Leave a comment


  1. Altus

     /  06/04/2012


    Not sure how memories work with infants. I have just been reading about memory in adults. I’ve read a bunch of articles on PKMzeta, including ones in scientific journals, but attached is a link of one of the more readable ones. ZIP is not in the brain…it is an enzyme that undoes PKMzeta a protein which is the glue of memories and is needed everytime you recall something (reconsolidate) to hold the memory together. Memories are fragile and can break down without the right amount of PKMzeta or be altered through the reconsolidation process by information that comes in or is lost during reconsolidation. As an experiment with 9-11 memories in people shows, the act of accessing a memory corrupts it. Still, many therapists hold onto the old “flashbulb” idea of memory.

    The fact that Mosaics might be being fed concepts of memory (and diagnosed) by a therapist who probably has no understanding of medicine or science is a little concerning. This is how the repressed memory movement got going. It’s was a belief system of therapists feeding impressionable patients…it’s not science and it’s dangerous. So wonder the DSM is under fire and insurance companies are demanding therapy be more rooted in research. Leading someone to dangerous conclusions based on untested theories and beliefs has no place in healthcare.


    • Altus,

      Another aspect that needs to be added is the vulnerability of patients and their probable distress experienced when seeking mental health treatment. These people (including me) can be taken advantage of and may not understand, for example, papers signed before admittance to a hospital is permitted. That too, happened to me.


  2. Jessica

     /  06/04/2012

    as part of my ba i took a course on neuromotor science of children, could have sworn they said that children can’t make reliable memories that can be recalled in adult hood til 3 yrs to 5 yrs. I’ll have to see if i can refind the book from it.


  3. Altus

     /  06/04/2012

    The neurons are only part of the picture. There is a glue that holds them together called PKMzeta which is a protein.This protein has to be in place to maintain memory. Experiments show that an enzyme called ZIP can counteract the glue effect of PKMzeta and inhibit memory reconsolidation until the memory is erased. Every time you recall something you are “reconsolidating” it by reorganizing it in your brain…if the glue goes so does the ability to reorganize the memory—and all fear that goes with it. What neuroscience shows is that memories are very, very fragile. These old Freudian theories of memory that were just pulled out the air by people who have no knowledge of science and have never stepped into lab are just ideas, but sadly people treat them of fact.


    • Very interesting, Altus.

      Question. Do humans have ZIP or PKMzeta when an infant?

      The belief that humans can create memories after a few months old is, as you know, is often reported.



What do you think?

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s