Hi Jean,

I know the body reacts to anxiety by releasing hormones such as adrenaline and cortisol, which together promote a psychotic paranoid response.

As far as Neurologically goes, I find it interesting how environmental influences affects us.
Research has found that EMF levels emitted by a CRT computer monitor or a television can produce the same paranoid sensation of someone watching you and can affect the brain for over an hour after exposure to the field.

Paranoia can be accompanied by a number of illnesses too. It’s association is with certain neurological conditions, such as temporal lobe epilepsy and some forms of dementia associated with aging, such as Alzheimer disease. The cause can be from repeated use of drugs such as cocaine or amphetamines. Paranoia is also known to be associated with mental disorders such as schizophrenia and paranoid personality disorder.

Shan

@Jean 997 wrote:

What the type of hormonal/immun/neuronal signal increase paranoïa ?

Paranoia is extreme fear regarding the motivation of others.

Paranoia has a psychological (learned) component, a signaling component, and possibly a structural component.

Paranoia may be an adaptive response or a maladaptive exaggerated response or a psychotic symptom.

When a black man, for example, is repeatedly accosted for no reason by the police, who may be racially profiling people or who may themselves be engaging in illegal activities, then the person experiencing this may develop paranoia about the police which has a realistic and adaptive component (e.g. how to avoid being sent to prison when one is innocent).

When a soldier is at war, one may not even trust civilians – even children – since they may be carrying weapons or bombs. One learns they may have to kill such civilians or children for self-preservation. .

When in prison, one may not know when one will be assaulted, raped, or killed. Thus one learns to become paranoid as an adaptive response.

In these cases, paranoia starts with an environmental threat. This leads to the autonomic nervous systems reaction of elevated norepinephrine signaling, which starts a cascade of defensive reactions within the mind/body. The stressor and the autonomic responses leads to paranoia as a learned and autonomic behavior.

This behavior may become maladaptive when the threat is no longer there – such as when the black man moves to a good neighborhood with decent police, the soldier comes back from war, or the prisoner is paroled. The learned and autonomic components of the behavior may be ingrained and will have to be undone through experience or therapy.

When excessive norepinephrine signaling activates abnormal circuitry in the nervous system which results in illogical processing of information, then the paranoia may become delusional or psychotic. This means it becomes an indelible false belief, which can’t be challenged even by evidence to the contrary. The person may not even have awareness that it is a false belief since the illogical circuitry impairs judgment or prevents insight that something is wrong. Such is the case when someone has a mental illness such as paranoid schizophrenia.

The reverse process may also occur. Illogical circuitry may result in an exaggerated assessment of threat, which then leads to excessive norepinephrine signaling. The illogical circuitry then causes the mind to attempt to find a cause for the norepinephrine signaling. This results in an external object being identified as the cause of the fear response. This results in a paranoid delusion if the illogical circuitry prevents appropriate assessment of the threat.

With this pathophysiology in mind, paranoid delusions generally indicate the presence of both a psychotic illness and a mood disorder (the fear component).