What Changes Occur In The Brain During The Teenage Years

The encephalon simmers with activity. Different groups of neurons (nerve cells), responsible for different thoughts or perceptions, drift in and out of action.

Memory is the reactivation of a specific group of neurons, formed from persistent changes in the strength of connections between neurons. But what allows a specific combination of neurons to be reactivated over any other combination of neurons?

The reply is synaptic plasticity. This term describes the persistent changes in the strength of connections – called synapses – betwixt brain cells. These connections can be made stronger or weaker depending on when and how ofttimes they have been activated in the past. Active connections tend to get stronger, whereas those that aren't used get weaker and can eventually disappear entirely.

A connection between two neurons becomes stronger when neuron A consistently activates neuron B, making it fire an action potential (spike), and the connection gets weaker if neuron A consistentlyfailsto make neuron B burn a spike. Lasting increases and decreases in synaptic forcefulness are called long-term potentiation (LTP) and long-term depression (LTD).

Irresolute the forcefulness of existing synapses, or even adding new ones or removing one-time ones, is critical to memory formation. Just in that location is too prove that another blazon of plasticity, not directly involving synapses, could be important for retention formation. In some parts of the adult brain, such as the important retentivity structure known as the hippocampus, brand new neurons can exist created in a process called neurogenesis. Studies in older mice accept shown that by increasing neurogenesis in the hippocampus, memory can be improved. In humans, exercise has been shown to increase the volume of the hippocampus – suggesting new neurons are being created – and at the aforementioned time improve functioning in retention tasks.

Different 'neuron ensembles' for dissimilar memories

Memories occur when specific groups of neurons are reactivated. In the brain, any stimulus results in a particular pattern of neuronal activeness—certain neurons become active in more than or less a particular sequence. If yous think of your cat, or your abode, or your fifth birthday cake, dissimilarensembles, or groups, of neurons get agile. The theory is that strengthening or weakening synapses makes particular patterns of neuronal activeness more or less probable to occur.

As a v-yr-old, if given the give-and-take 'business firm', yous might have imagined a drawing of a firm. As an adult, upon hearing the same word you may well picture your own house—a different response for the same input.

This is because your feel and memories accept changed the connections between neurons, making the sometime 'house' ensemble less likely to occur than the new 'house' ensemble.

In other words, recalling a retentivity involves re-activating a particular group of neurons. The idea is that past previously altering the strengths of detail synaptic connections, synaptic plasticity makes this possible.

Memories are stored past irresolute the connections between neurons. A 5-year-erstwhile child will activate a certain group of neurons (Ensemble A); whereas adults will actuate a dissimilar ensemble (Ensemble A') with the same stimulus. Synaptic plasticity driven by repeated feel can change the connection strengths between neurons. This is how there can exist the different neuronal responses to the aforementioned input. (Image: Alan Woodruff / QBI).

Sleep is important for retention formation

Sleep is some other of import factor for memory storage. During sleep, the hippocampus and neocortex take function in a carefully choreographed dialogue in which the hippocampus replays contempo events: the aforementioned hippocampal neurons agile during an experience become activated again during slow-wave sleep, over and over in a time-compressed manner, helping to update the neocortex every bit to what needs to be stored. This replay only occurs during sleep, and then if you lot're skimping on sleep, you lot aren't letting your encephalon consolidate memories.