Read This On Our Main Website: https://psoec.com/seizures-and-memory-problems-in-epilepsy-can-have-a-common-cause/?feed_id=906&_unique_id=61b000ebcb535
[ad_1]
Summary: Deficits in dentate gyrus operate that trigger reminiscence issues could also be linked to epileptic seizures, studies a brand new research. The irregular exercise results in over-extinction, which results in seizures.
Source: University of Wisconsin-Madison
Damage to part of the mind that regulates hyperactivity can contribute to each reminiscence issues and seizures in the commonest type of epilepsy, based on a research by the University of Wisconsin-Madison.
The research just lately revealed within the Journal of Neuroscience, could result in an earlier analysis of epilepsy and doubtlessly new methods to deal with epilepsy and different circumstances with widespread signs equivalent to Alzheimer's illness, traumatic mind damage, and autism spectrum dysfunction.
Temporal lobe epilepsy, characterised by seizures within the studying and reminiscence facilities of the mind, impacts greater than half of the three.4 million individuals within the United States identified with epilepsy. A portion of the temporal lobe known as the dentate gyrus has lengthy been suspected of appearing as a gate - it helps management mind exercise by being choosy about which patterns of mind cells are lively and that are silenced.
"You can think of any pattern as a memory," says Antoine Madar, now a postdoctoral fellow on the University of Chicago, who performed the analysis whereas doing his PhD at UW-Madison within the laboratory of neuroscience professor Matt Jones. “A sample represents the first visit to an art museum. Another, similar pattern will be your second visit to the museum. "
The unique features of each memory can be subtle - from the specific art you admired, different friends for the experience, or even the time of day - but they are important in guiding certain memories. Researchers like Madar hypothesized that the dentate gyrus helps differentiate between similar memories and holds back all but the matching patterns to avoid confusion.
“In epilepsy, there is this huge rewiring of the dentate gyrus. Some cells die, some new neurons and new connections between neurons are added in the wrong places, ”says Madar. "This is a dramatic distinction to a wholesome dentate gyrus."
This rewiring, together with molecular adjustments in any cell, allows seizures to develop. However, it's unclear how this reorganization of the dentate gyrus impacts reminiscence.
With the assistance of UW Madison neurologists Bruce Hermann and Rama Maganti, the researchers examined sufferers within the epilepsy monitoring unit on the UW School of Medicine and Public Health and requested them to carry out picture recognition assessments. These assessments confirmed that they'd problem distinguishing between related recollections in comparison with wholesome individuals of the identical age and gender.
The researchers additionally studied a mouse mannequin of epilepsy and examined their reminiscence by repeatedly releasing them into an enviornment with two an identical objects. Every time a mouse returned to the world, one of many objects was moved to a special location.
“Normal mice noticed and acted like something was different. They spent extra time exploring the property, which was in a new location, ”says Jones, whose work is supported by the National Institutes of Health. “Mice with epilepsy were examined, but they showed no preference for any object; they acted as if nothing had changed and mistook the new situation for their memory of the old one. "
In search of the cause of this confusion, Madar examined brain tissue from mice that had been subjected to a memory test. With a series of specific electrical impulses, he stimulated the nerve fibers that serve as entrances to the dentate gyrus and recorded the patterns of neural activity at the exit of the dentate gate.
In healthy mice, similar input patterns were converted into easily distinguishable patterns of output activity by the dentate gyrus network. The input patterns simulated different but similar memories. This process was interrupted in epileptic mice. A subset of the neurons did not do their job of separating patterns. Instead of transmitting a single pulse from Madar's electrodes, the epileptic neurons would transmit bursts of pulses.
“We wonder if the same deficiencies in the functioning of the dentate gyrus that cause memory problems are also causing the susceptibility to these seizures,” says Jones. "This abnormal activity leads to overexcitation, which leads to seizures."
The new research, supported by Madison's Lily's Fund for Epilepsy Research, improves our understanding of reminiscence mechanisms and hyperlinks the organic operate of the dentate gyrus and the flexibility to keep away from reminiscence confusion. This may result in higher look after sufferers with epilepsy and related issues with reminiscence impairment or seizures, particularly if the brand new findings assist researchers differentiate between broken and usually functioning mind cells.
"Identifying markers that specifically target pathological neurons could enable treatment of seizures and memory symptoms with fewer side effects than current anti-seizure drugs," says Madar.
Since reminiscence issues usually precede the seizure resulting in a analysis of epilepsy, they may very well be used to assist diagnose sufferers earlier.
"Take someone who has suffered a head injury: they could evaluate their own memory on a regular basis using inexpensive, non-invasive computer-based tests like the ones we have used," says Jones. "If you start to show progressive deficits, a doctor might suggest treatment to make sure you never have a first attack."
About this epilepsy and reminiscence analysis information
Author: Chris Barncard
Source: University of Wisconsin-Madison
Contact: Chris Barncard - University of Wisconsin-Madison
Image: The image is within the public area
Original analysis: Closed entry.
"Deficits in the separation of behavior and neural patterns in temporal lobe epilepsy“By Antoine D. Madar, Jesse A. Pfammatter, Jessica Bordenave, Erin I. Plumley, Swetha Ravi, Michael Cowie, Eli P. Wallace, Bruce P. Hermann, Rama K. Maganti, and Mathew V. Jones. Journal of Neuroscience
abstract
See additionally
Deficits within the separation of conduct and neural patterns in temporal lobe epilepsy
In temporal lobe epilepsy, the ability of the dentate gyrus to limit excitatory cortical input to the hippocampus breaks down, causing seizures. The dentate gyrus is also believed to help distinguish between similar memories by performing pattern separation, but whether epilepsy leads to a breakdown in this neural computation and thereby impairment of mnemonic distinction remains unknown.
Here we show that temporal lobe epilepsy is characterized by behavioral deficits in mnemonic differentiation tasks in both humans (females and males) and mice (C57Bl6 males, systemic low-dose kainate model). With a recently developed assay in brain slices from the same epileptic mice, we show a decreased ability of the dentate gyrus to perform certain forms of pattern separation. This is due to a subset of granular cells with abnormal bursting that can develop independently of early EEG abnormalities.
Overall, our findings, which combine physiology, computation, and cognition in the same mice, improve our understanding of episodic memory mechanisms and their dysfunction in epilepsy.
EXPLANATION OF MEANING
People with temporal lobe epilepsy (TLE) often have learning and memory disorders that sometimes occur before the first attack, but little is known about these symptoms and their biological basis.
We focused on the dentate gyrus, a region of the brain that is critical to avoid confusing similar memories and is anatomically disorganized in TLE. We show that both humans and mice with TLE experience confusion between similar situations. This impairment coincides with a failure of the dentate gyrus to distinguish similar input signals due to pathological bursting in a subset of neurons.
Our work combines seizure and memory-oriented views of dentate gyrus operate, suggests a mechanism for cognitive signs in TLE, and helps a long-standing speculation of episodic reminiscence theories.
[ad_2]
Read This On Our Main Website: https://psoec.com/seizures-and-memory-problems-in-epilepsy-can-have-a-common-cause/?feed_id=906&_unique_id=61b000ebcb535
Comments
Post a Comment