Psychoneuroimmunology- the study of interaction between psychological processes and the nervous and immune systems of the human body.

1. Psychoneuroimmunology
SAGNIKA PANDA
CMBt 4th Semester

2. What is Psychoneuroimmunology
(PNI)?
❖“Psycho” means thoughts and emotions.
❖“Neuro” means that the physical brain is
involved.
❖“Immunology” is a branch of biology that covers
the study of immune systems in all organisms.
❖It is the study of interaction between
psychological processes and the nervous and
immune systems of the human body.

4. Origins
❖In 1975, Robert Ader and Nicholas Cohen coined
the term “Psychoneuroimmunology”.
❖They demonstrated “Classic conditioning” of the
immune system.
❖In the 1970s, Hugo Besedovsky, Adriana del Ray,
and Ernst Sorkin proposed that the immune system
acts as a sensorial receptor organ that can
communicate to the brain and associated neuro-
endocrine structures its state of activity.

5. Robert Ader Nicholas Cohen

6. Why is PNI an interesting field?
❖Prolonged stress and specific traumatic experiences change
the biochemistry of your brain and your hormones.
❖Stressful emotions also reduce the numbers and
effectiveness of immune system cells, including the
inflammation response, the t cells and the Natural Killer cells,
the macrophages, etc.
❖People who were abused or neglected as children can have
a permanent effect on their brain chemistry and the immune
system as a result.
❖Even loneliness can lead to immune system suppression.

7. How psychological factors affect our
immune system & vice-versa?
❖The nervous system affects the endocrine system via the pituitary
gland, controlling hormone secretion.
❖The endocrine system modulates the immune system through the
hormones secreted by the pituitary and adrenal glands. The HPA axis
plays a central role, as immune cells are equipped with receptors for
HPA molecules, and are altered in number, function, and distribution
as a result of the hormones secreted.
❖Through the autonomic nervous system, the nervous system has
direct effects on the immune system via the thymus gland, the
spleen, and bone marrow.
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8. How psychological factors affect our
immune system & vice-versa?
❖Cytokines produced by Th cells also impact the central nervous
system and the HPA axis.
❖Studies indicate that cytokines and their signaling pathways have
significant effects on the metabolism of multiple neurotransmitters
such as serotonin, dopamine and glutamate through impact on their
synthesis, release and reuptake.
❖Through their effects on neurotransmitter systems, cytokines impact
neurocircuits in the brain including the basal ganglia and anterior
cingulate cortex, leading to significant changes in motor activity and
motivation as well as anxiety, arousal and alarm.

9. How does increased stress lead to
immunomodulation?

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12. Stress Management
❖ Physical activity
▫ Increases neurotrophin (neuron growth factor) expression in
cortex and hippocampus
▫ Increases neurogenesis in dendate gyrus of hippocampus
❖ Pharmaceutical agents
▫ Sleep medication
▫ Antidepressants
❖ Social support and counseling.

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Thank You!!!