After a traumatic brain injury, why do some people quickly regain their skills while others face long-lasting setbacks? The researchers have been trying to answer this question by understanding which parts of the brain are used to process sensory information and remember different skills.
"From a biomedical standpoint, the question is whether certain parts of the brain are solely responsible for] certain types of function," says the senior author. The latest research published in Neuron, could eventually help us determine which abilities are particularly difficult to recover after a traumatic brain injury--likely because these skills are represented in only one area of the brain--and which are more resilient.
The team created a memory game for mice in order to examine the function of two brain areas that process information about the sensation of touch and the memory of previous events--areas of the brain they called S1 and S2. They wanted to see whether S1 and S2 both processed the same information (distributed processing), or if the areas each had specialized, independent roles (localized processing).
Mice were presented with a memory game that gently stimulated their whiskers with a moving device. For the mice, the goal of the game was to recognize whisker movement patterns to receive a reward. First, each mouse felt the device move its whiskers either forward or backward. Then, after a two-second pause, the device moved their whiskers again. If their whiskers were moved in opposite directions during both rounds--for example, if the device moved the whiskers forward first, paused, and then moved the whiskers backward--the mice learned they could lick a straw to receive a thirst-quenching drink. On the other hand, if the device moved their whiskers in the same direction during both rounds, the mice were supposed to refrain from licking. If the mice got it wrong, they instead received a small puff of air and a timeout before they could resume the game.
Meanwhile, the researchers were observing the mice's brain activity throughout the game and seeing how the S1 and S2 areas impacted the mice's skills. They used a technique called optogenetics, a genetic engineering method that allowed them to selectively activate groups of brain cells in the S1 or S2 areas of the mice's brains using light.
The researchers found that the S1 and S2 areas of the mice's brains do a lot of the same processing, frequently sending information back and forth to each other. But they also observed that the two brain areas carried out some specialized roles while the mice played the memory game. S1 seems to be more involved in processing immediate sensory information, making sense of how the mice's whiskers move in real time. In contrast, S2 seems to be particularly involved in helping the mice recall past events, with the mice relying on this brain area to remember what happened in the first round of the game.
The findings suggest that S1 and S2 are wired differently, as the brain cells in S2 are more strongly connected with each other than the brain cells inside S1. The authors speculates that these stronger connections relate to S2's role in recalling the past. When brain cells are more connected, it may be easier for a cue to set off a chain of cells and trigger a memory--a "domino effect" of neural activity. Together, the localized and distributed processing roles of S1 and S2 both contributed to the mice being able to correctly play the game and earn a sugary snack.
Although humans don't have whiskers, the team's experimental observations could represent the same kind of sensory information processed by human hands.
"We have just as much sensitivity and dexterity to process tactile information with our fingers as a mouse has with its whiskers," the senior author says. "So, if we were to study how we process tactile information in our hand and fingers, we might expect to see just as much distributed power as we would [in a mouse], because that's what we've evolved to use as one of our main senses."
Before these findings can help humans suffering from long-lasting loss of motor skills or other abilities after traumatic brain injury, the author says there's still a lot of research to be done.
"One factor to keep in mind is that a mouse has a smaller brain [than a human], and some of these areas are much more intermingled, so the processing in a mouse brain might be more distributed," the author says.
http://www.bu.edu/articles/2020/how-a-memory-game-for-mice-could-help-us-understand-the-effects-of-brain-injury/
https://www.cell.com/neuron/pdf/S0896-6273(20)30103-3.pdf?
Context-Dependent Sensory Processing in Mouse Brain
- 1,005 views
- Added
Edited
Latest News
More influence of environme…
By newseditor
Posted 24 Apr
The assembly of the human c…
By newseditor
Posted 24 Apr
Wiring of the human neocortex
By newseditor
Posted 24 Apr
Abusive drugs hijack natura…
By newseditor
Posted 23 Apr
Mechanism of action of the…
By newseditor
Posted 23 Apr
Other Top Stories
Copper is key in burning fat
Read more
How altered gut microbes cause obesity
Read more
Receptor in nasal cavity may be linked to preference for high-fat food
Read more
Signaling molecules can make neuronal extensions retract at a distance
Read more
Hunger' neurons in the brain are regulated by protein activated dur…
Read more
Protocols
A programmable targeted pro…
By newseditor
Posted 23 Apr
MemPrep, a new technology f…
By newseditor
Posted 08 Apr
A tangible method to assess…
By newseditor
Posted 08 Apr
Stem cell-derived vessels-o…
By newseditor
Posted 06 Apr
Single-cell biclustering fo…
By newseditor
Posted 01 Apr
Publications
Distinct genetic and enviro…
By newseditor
Posted 24 Apr
Hippocampus-to-amygdala pat…
By newseditor
Posted 24 Apr
Integrative spatial analysi…
By newseditor
Posted 24 Apr
Time-series reconstruction…
By newseditor
Posted 24 Apr
Harnessing gastrointestinal…
By newseditor
Posted 24 Apr
Presentations
Hydrogels in Drug Delivery
By newseditor
Posted 12 Apr
Lipids
By newseditor
Posted 31 Dec
Cell biology of carbohydrat…
By newseditor
Posted 29 Nov
RNA interference (RNAi)
By newseditor
Posted 23 Oct
RNA structure and functions
By newseditor
Posted 19 Oct
Posters
A chemical biology/modular…
By newseditor
Posted 22 Aug
Single-molecule covalent ma…
By newseditor
Posted 04 Jul
ASCO-2020-HEALTH SERVICES R…
By newseditor
Posted 23 Mar
ASCO-2020-HEAD AND NECK CANCER
By newseditor
Posted 23 Mar
ASCO-2020-GENITOURINARY CAN…
By newseditor
Posted 23 Mar