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## Explain what an action potential is, and describe how it moves down the axon and across the synapse?

reudhreghs
Featured 6 months ago

The action potential (electrical impulse) is pulled along the cell by positive ions entering and attracting it before leaving again.

#### Explanation:

An action potential is the electrical signal that travels down the neuron cell.

The electrical signal is negatively charged, because it is, obviously, electrical. It is drawn along the neuron by a series of positive ions appearing in front of it and pulling it forward. Imagine if you tied a string to a ten pound note and pulled it along the street with a cartoon character chasing after it - that's how I like to think of it.

The inside of the neuron cell is normally negatively charged relative to the outside. Ion channels open when the electrical signal enters the cell and pump $N {a}^{+}$ ions inside, which attracts the electrical signal along the cell.

Since the cell is normally negative, or polar, the influx of positive ions is known as a depolarisation, because it turns the cell more positive in that area. However, once the cell has reached a certain level of depolarisation, the $N {a}^{+}$ supply cuts off and the cell begins pumping ${K}^{+}$ ions out of the cell instead. This turns the cell back to negative, causing a repolarisation.

While this is happening, some of the $N {a}^{+}$ spreads out and changes the charge slightly further along the cell, which activates more sodium gates and lets sodium flow in further along, which depolarises that segment of the axon and pulls the electrical signal even further along.

The series of depolarisation and repolarisation along the cell makes the action potential move down the axon.

When an electrical impulse reaches the synapse, it opens calcium channels. The calcium enters and causes vesicles (bubbles) of neurotransmitters to bind to the membrane and release the chemicals. The neurotransmitter molecules drift across the synapse and bond to receptors on the next neuron, which initiates the electrical signal and the process of de- and repolarisations repeats.

## What are the consequences of attachment theory?

Margaret
Featured 9 months ago

When the figure of attachment isn't there, the person attached starts feeling distressed.

#### Explanation:

The attachment theory was first introduced by John Bowlby in 1958. The theory describes interpersonal relationships between humans, but mainly focuses on infants' needs to be physically close to at least one primary caregiver.

Bowlby presented the main concepts of the theory, which were:

1. Infants seek proximity to attachment figures (usually the parents) because these would protect them if they were to face any dangers.

2. Proximity-seeking behaviours developed over the course of evolution because as mentioned previously, being close to one's parents provides security for the infant.

3. This attachment system is the most important during the early years of one's life, however, attachment is also vital later in life, especially during the adolescent years. A lack of attachment can often lead to the development of a range of neurological disorders.

Bowlby also described what it takes for a person to become attached to another person.

1. The figure of attachment is there in times of need.
2. The figure of attachment provides a physical and emotional "safe haven". This means that the person attached feels secure and comfortable when in the presence of their partner.
3. The figure of attachment provides a safe environment for a person to learn, explore, to develop their personality and to accomplish their goals.

When the above points are met, the partner then becomes a source of attachment.

The consequence of meeting the points listed above is that when one becomes attached to another person, he or she inevitably becomes dependent on them, too. This means that in times of separation from the figure of attachment, he or she tends to feel distressed.

Attachment figures tend to promote positive views about self and the world. However, when the figure of attachment is unavailable or begins to fail to meet one's expectations, the person attached might form negative representations of self and others. (low self-esteem and a pessimistic view of the world)

## What is a perceptual set?

Parzival S.
Featured 6 months ago

Perceptual set is a tendency to perceive or notice some aspects of the available sensory data and ignore others.

#### Explanation:

Our bodies are magnificent machines. One of the ways they demonstrate this is by taking repetitive motions and actions and reducing the resources needed to perform them. For instance, when a baby is learning to walk, each step is planned and performed. But after a relatively short period of time, they are running without giving it a thought - they just run (and run and run and run...)

Our brains do the same thing. The world is full of information that continually enters our senses. In order to speed up processing time and reduce the energy needed to perform those functions, it operates largely on what is expected and not necessarily on what is actually there.

And that is what Perception Set Theory gets into - how the brain "perceives" - or as the below link describes it - "Perceptual set theory stresses the idea of perception as an active process involving selection, inference and interpretation."

Perceptual set is a tendency to perceive or notice some aspects of the available sensory data and ignore others. For instance, have you ever seen this:

Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a toatl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.

The brain doesn't read every word but instead selects out important bits and teases out the rest based on expectation and inference.

Another kind of perceptual set is when we have a fear of snakes, to automatically assume that every suspicious looking thing in the grass is a snake - even though most times we're looking at a garden hose.

There are a number of ways perception sets can change. If we're hungry, the perception set will tend to look for food over other things.

http://www.simplypsychology.org/perceptual-set.html

## What is the opposite of anthropomorphism?

Parzival S.
Featured 6 months ago

Depending on how you define the opposite of anthropomorphism, it could be one of a few words. I suggest zoomorphism, dehumanize, and deanthropomorphism as possibilities.

#### Explanation:

Anthropomorphism is the attribution of human-like qualities onto non-human subjects, such as inanimate objects, plants, animals, and the like.

There would then be a couple of different ways we could find a word meaning the opposite. One would be a word that refers to the attribution of animal-like qualities onto a human. That word is zoomorphism. Examples include calling someone a "dirty dog", a "skunk", a "snake", etc.

Another way to take the opposite would be to have a word that refers to the removal of human-like traits from a human. That word is dehumanize.

The last way I can see an opposite is by finding a word that refers to the removal of human-like traits from non-humans. I think the best word for that would be deanthropomorphism

## How are night terrors related to psychosis?

Cara_Rose
Featured 1 month ago

They are both believed to be the result of excess dopamine

#### Explanation:

Although the causes of different sleep and personality disorders remain disputed by researchers. It is generally accepted that psychosis is the result of excess dopamine and over-activation of the dopaminergic system; similarly night terrors, a type of sleep disorder common in younger individuals is thought to also be associated with higher levels of dopamine.

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