How psychedelics affect cognitive processes

Question 1

Hoe hebben psychadelica invloed op cognitieve processen?

Answer 1

Psychedelics act on serotonin receptors: highly distributed in the brain: high concentration in higher order association regions. Anterior temporallobe: integrating semantic information. Temporal parietal adjunction: multisensory integration from different senses. Medial prefrontal cortex: self-reflection and daydreaming. So  intervention at a high level in consciousness.

Question 2

Filter theory (thalamic filter hypothesis)

Answer 2

thalamus normally filters theinformation we receive: prefrontal cortex determines this. Under the influence of psychedelics, the prefrontal cortex is more active and thus the filter is “released”. So more sensory information is being sent to the brain  overwhelming experience of sensory stimuli

Question 3

Default mode network (DNM) model:

Answer 3

he DNM contains self-reflection and daydreaming etc. Psychedelics work primarily by breaking through the state of self-reflection, so breaking through the state of DMN.In the case of a task-positive network, the opposite is true: works proportionally. So, these two networks are balanced to each other. DMN also plays a role in depression: being stuck in your own thoughts and a strong focus on yourself. The DMN is less active under the influence of psychedelics so the continuous state of self-reflection is interrupted. This mechanism helps to understand how experience of loss of self under the influence of psychedelics can influence depression (mainly positive)

Question 4

Entropic brain hypothesis

Answer 4

under the influence of psychedelics, brainareas that do not normally communicate with each other suddenly make connections with each other. Brain areas normally communicate strongly with themselves. Under the influence of psychedelics, connections within networks decrease and between networks increase. DMN decreases,
Task-positive network increases, connection between them increase. This gives the possibility to e.g. feel colors or merge with architecture itself

Question 5

Predictive processing model

Answer 5

the brain is a predictive machine that continuously makes predictions about the world. Under the influence of psychedelics, that predictive machine is interrupted: more surprises and more open to the new experiences that are coming your way. REBUS model known within this: Loosening the precision of high-level priors, resulting in more sensitivity to bottom-up prediction errors. Consequenceof action predicts less well: moving hand resembles afterimage: because this does not predict that you will do this