Navigation Links
IU discovery on animal memory opens doors to research on memory impairment diseases

BLOOMINGTON, Ind. -- If you ask a rat whether it knows how it came to acquire a certain coveted piece of chocolate, Indiana University neuroscientists conclude, the answer is a resounding, "Yes." A study newly published in the journal Current Biology offers the first evidence of source memory in a nonhuman animal.

The findings have "fascinating implications," said principal investigator Jonathon Crystal, both in evolutionary terms and for future research into the biological underpinnings of memory, as well as the treatment of diseases marked by memory failure such as Alzheimer's, Parkinson's and Huntington's, or disorders such as schizophrenia, PTSD and depression.

The study further opens up the possibility of creating animal models of memory disorders.

"Researchers can now study in animals what was once thought an exclusively human domain," said Crystal, professor in the Department of Psychological and Brain Sciences in the College of Arts and Sciences. "If you can export types of behaviors such as source memory failures to transgenic animal models, you have the ability to produce preclinical models for the treatment of diseases such as Alzheimer's."

Of the various forms of memory identified by scientists, some have long been considered distinctively human. Among these is source memory. When someone retells a joke to the person who told it to him, it is an everyday example of source memory failure. The person telling the joke forgot the source of the information -- how he acquired it -- though not the information he was told. People combine source information to construct memories of discrete events and to distinguish one event or episode from another.

Nonhuman animals, by contrast, have been thought to have limited forms of memory, acquired through conditioning and repetition, habits rather than conscious memories. The kind of memory failures most devastating to those directly affected by Alzheimer's have typically been considered beyond the scope of nonhuman minds.

The study owes much to another quality these rodents share with humans: They love chocolate. "There's no amount of chocolate you can give to a rat which will stop it from eating more chocolate," Crystal said.

Using chocolate as bait in an eight-arm radial maze, the study was made up of a series of five experiments that together provide converging evidence. In the first two, in order to obtain the chocolate, the rats needed to remember the source by which they acquired it, whether they were placed near the trough containing the chocolate or had to run on their own to get there. Using different mazes helped rule out the possibility that overlearned cues from a particular maze led to the positive results.

A third experiment showed that the rats' source memory, the means by which it retrieved the chocolate, lasted for a week rather than the one day that other, more ordinary forms of memory last. This provided converging evidence, said Crystal, that the rats were relying on source memory insofar as source memories decay more slowly than other memory systems.

In the fourth experiment, the rats could obtain the chocolate when the researcher placed them at the trough. The rats remembered this rule, too. Finally, in the fifth experiment, researchers temporarily disabled the rats' hippocampus, the brain region thought to be crucial for accurate source memory. If the task requires source memory, inactivating that area would impair the ability to remember source information, which it did.

"What we're trying to do is to develop behavioral approaches with rodents that tap into those types of memory systems," Crystal said. "This study is the demonstration, the proof of the concept that source memory exists in animals. But the mechanism that supports it is open. We're now interested in working out the sub-areas of the hippocampus that are involved in episodic memory, testing hypotheses about different regions being involved in short-term and long-term episodic memory, working out the neuroanatomical pathways."


Contact: Liz Rosdeitcher
Indiana University

Related biology news :

1. Cell discovery could hold key to causes of inherited diseases
2. New scorpion discovery near metropolitan Tucson, Arizona
3. The discovery of a new genus of crustacean and 5 new species
4. A*STAR scientists groundbreaking discovery of nucleus structure crucial to understanding diseases
5. Discovery of sexual mating in Candida albicans could provide insights into infections
6. New discovery in autism-related disorder reveals key mechanism in brain development and disease
7. Discovery of Africa moth species important for agriculture, controlling invasive plants
8. Discovery may pave way to genetically enhanced biofuel crops
9. LSUHSC research discovery provides therapeutic target for ALS
10. Discovery of pathway leading to depression reveals new drug targets
11. Discovery of 100 million-year-old regions of DNA shows short cut to crop science advances
Post Your Comments:
Related Image:
IU discovery on animal memory opens doors to research on memory impairment diseases
(Date:11/4/2015)... 2015 --> ... by Transparency Market Research "Home Security Solutions Market - Global ... - 2022", the global home security solutions market is expected to ... The market is estimated to expand at a CAGR ... 2022. Rising security needs among customers at homes, the ...
(Date:10/29/2015)... , Oct. 29, 2015  Rubicon Genomics, ... for U.S. distribution of its DNA library preparation ... and Rubicon,s new ThruPLEX Plasma-seq kit. ThruPLEX Plasma-seq ... the preparation of NGS libraries for liquid biopsies--the ... diagnostic and prognostic applications in cancer and other ...
(Date:10/27/2015)... 27, 2015 Munich, Germany ... Mapping technology (ASGM) automatically maps data from mobile eye ... , so that they can be quantitatively analyzed ... Munich, Germany , October 28-29, 2015. SMI,s ... from mobile eye tracking videos created with SMI,s ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... ... November 24, 2015 , ... InSphero AG, the leading supplier ... models, has promoted Melanie Aregger to serve as Chief Operating Officer. , ... the management team and was promoted to Head of InSphero Diagnostics in ...
(Date:11/24/2015)... 2015 /CNW Telbec/ - ProMetic Life Sciences Inc. (TSX: PLI) ... Pierre Laurin , President and Chief Executive Officer of ... Piper Jaffray 27 th Annual Healthcare Conference to be ... 2015. st , at 8.50am (ET) and ... the day. The presentation will be available live via a ...
(Date:11/24/2015)... , Nov. 24, 2015 HemoShear ... on discovering drugs for metabolic disorders, announced today ... to its Board of Directors (BOD). Mr. Watkins ... of Human Genome Sciences (HGS), and also served ... Jim Powers , Chairman and CEO ...
(Date:11/24/2015)... YORK , November 24, 2015 ... in a European healthcare ... which the companies will work closely together in identifying European ... unmet medical need. The collaboration is underpinned by a significant ... fund. This is the first investment by Bristol-Myers Squibb in ...
Breaking Biology Technology: