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There has been some truth behind the concept of memory alteration.

Has there been some truth to this concept? Yes, there has been some truth to this concept.

Scientists have discovered a way to alter memories. They have used mice as test subjects.

Who has discovered a way to alter memories? Scientists have discovered a way to alter memories. What kind of test subjects have they used? They have used mice as test subjects.

The scientists have discovered a gene in the brain called the tet1 gene.

What gene have they discovered? They have discovered the tet1 gene. Who has discovered the tet1 gene? Scientists have discovered the tet1 gene.

This gene is responsible for memory extinction, which is the process of new memories replacing old memories. The theory is, the higher the activity of the tet1 gene, the easier it will be to erase old memories.

To test this theory, they have placed each mouse into a cage, where once inside, each mouse has received an electric shock.

Where have they placed each mouse? They have placed each mouse into a cage. What has happened next? Next each mouse has received an electric shock.

The mice have begun to associate the cage with the electric shock, which has been a traumatic experience for them.

What kind of experience has this been? This has been a traumatic experience.

Then the scientists have split the mice into two separate groups.

Have they split the mice into three groups? No, they haven’t split the mice into three groups. How many groups have they split the mice into? They have split the mice into two groups.

The first group has retained their tet1 gene as normal, while the second group has had their tet1 gene removed.

What has happened to the first group? The first group has retained their tet1 gene. What has happened to the second group? The second group has had their tet1 gene removed.

The mice have then been placed inside of the cage again, this time without having received an electric shock.

Over time, the mice with the normal tet1 gene have learned to not be afraid of the cage.

What have the mice with the normal tet1 gene learned? The mice with the normal tet1 gene have learned to not be afraid of the cage.

Their painful memories have faded over time.

What has faded over time? Their painful memories have faded over time.

Their new memories have been replaced by the old, traumatic memory of the electric shock, and they have no longer had anything to fear.

What have been replaced, their new memories or their old memories? Their old memories have been replaced.