Nav: Home

Scientists find first evidence for necessary role of the human hippocampus in planning

March 12, 2019

A team of scientists reports finding the first evidence that the human hippocampus is necessary for future planning. Its findings, published in the journal Neuron, link its long-established role in memory with our ability to use our knowledge to map out the future effects of our actions.

The results have implications for the way we think about afflictions that affect the hippocampus, like Alzheimer's disease, as not only impacting memory but also decision-making.

The work centers on the hippocampal "cognitive map," the brain's spatial localization system discovered by University College of London's John O'Keefe, who was awarded the 2014 Nobel Prize in Physiology or Medicine. The hippocampal cognitive map has been long thought to allow us to "mentally simulate" the future outcomes of our actions as we plan into the future. However, there had previously been no direct evidence in humans that the hippocampus is actually necessary for planning.

"Our results show that both goal-directed planning and remembering locations in space depend on the human hippocampus" says Oliver Vikbladh, a doctoral candidate at New York University's Center for Neural Science and the paper's lead author. "By clarifying the scope of hippocampal contributions to behavior, the study may have implications for diseases that affect the hippocampus, such as epilepsy and Alzheimer's disease."

"To better understand the contribution of the hippocampus to planning, we tested patients with epilepsy, a condition known to damage this brain region, and which is sometimes treated with surgical removal of damaged, hippocampal brain tissue," explains Orrin Devinsky, director of NYU Langone Medical Center's Comprehensive Epilepsy Center and a coauthor of the paper.

The study authors compared epilepsy patients to healthy adults, as both groups undertook computer-based tests that assessed their spatial memory and ability to plan into the future. Participants were asked to recall the locations of objects in a virtual-reality arena, and to perform another task that involved learning the relationship between actions and their outcomes and to plan using that knowledge. "These tasks aim to capture functions that let us find our car in a parking lot, or planning moves ahead in a game of chess by imagining how the game will play out," explains Vikbladh.

Their results revealed that, compared to non-epilepsy participants, epilepsy patients displayed inferior spatial memory and also showed a relative tendency to plan less. In fact, those with epilepsy more likely to form habits--repeating actions that had been rewarded in the past without considering their outcomes. The scientists also were able to link the planning deficit to the extent of hippocampal damage in the epilepsy patients.

"These findings are consistent with the long-held hypothesis that the hippocampus provides a 'cognitive map'--not only for spatial localization but also for planning into the future," observes Vikbladh. "More broadly, when we talk diseases that affect the hippocampus, such as Alzheimer's, we often focus on the memory deficits--such as forgetting where you are. But there might be additional challenges, specifically, an inability to plan properly. Given that approximately 50 million people suffer from Alzheimer's or related dementias, it is critical that we understand how damage to the hippocampus affects the way we make decisions."
-end-
The study was also led by researchers from Princeton University, Columbia University, and University College London, and was supported, in part, by a grant from the National Institutes of Health (DA038891).

DOI: 10.1016/j.neuron.2019.02.014

New York University

Related Epilepsy Articles:

Good news for kids with epilepsy
There's good news for kids with epilepsy. While several new drugs have come out in the last several years for adults with epilepsy, making those drugs available for children and teenagers has been delayed due to the challenges of testing new drugs on children.
People with epilepsy: Tell us about rare risk of death
People with epilepsy want their health care providers to tell them about a rare risk of death associated with the disorder, according to a preliminary study released today that will be presented at the American Academy of Neurology's 69th Annual Meeting in Boston, April 22 to 28, 2017.
New epilepsy gene network identified by scientists
Scientists have discovered a gene network in the brain associated with epilepsy.
Epilepsy -- why do seizures sometimes continue after surgery?
New research from the University of Liverpool, published in the journal Brain, has highlighted the potential reasons why many patients with severe epilepsy still continue to experience seizures even after surgery.
Redox biomarker could predict progression of epilepsy
Approximately 2.9 million people in the United States suffer from epilepsy, according to the CDC.
Many Malaysian children with epilepsy are vitamin D deficient
Long-term use of antiepileptic drugs is a significant risk factor for vitamin D deficiency in children with epilepsy.
Changes in heart activity may signal epilepsy
Researchers at Case Western Reserve University have found that the parasympathetic nervous system modulates breathing and slows the heart rate of sleeping children with epilepsy substantially more than in healthy children.
Few answers in understanding death from epilepsy
To increase understanding of mortality in epilepsy, including SUDEP, Partners Against Mortality in Epilepsy (PAME) unites physicians, scientists, health care professionals, people with epilepsy, caregivers and bereaved family members for a unique conference that facilitates collaboration and spurs action.
New insights into epilepsy drug Retigabine
A study published ahead of print in the Journal of General Physiology has revealed new insights into Retigabine, a known pharmacological treatment for epilepsy.
Are women with epilepsy using effective contraception?
In the largest study of contraceptive practices of women with epilepsy, 30 percent did not use highly effective contraception despite being at higher risk of having children with fetal malformations due to the anti-epilepsy medications they take.

Related Epilepsy Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Setbacks
Failure can feel lonely and final. But can we learn from failure, even reframe it, to feel more like a temporary setback? This hour, TED speakers on changing a crushing defeat into a stepping stone. Guests include entrepreneur Leticia Gasca, psychology professor Alison Ledgerwood, astronomer Phil Plait, former professional athlete Charly Haversat, and UPS training manager Jon Bowers.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".