Task 8: Altered states of consciousness Flashcards
Altered states of consciousness (ASC):
include drug-induced states, hypnosis, mental illness and mindfulness
How to define altered states of consciousness
a)OBJECTIVELY – define ASC in terms of how it was induced
Problem: how do we know whether two slightly different drugs produce the same or different ASCs? How can we measure similarity? What about dosage?
b) PHYSIOLOGICALLY AND BEHAVIORALLY – heart rate, cortical oxygen consumption, ability to walk in a straight line, expressions of emotions, etc.
Problem: very small changes in physiology may be associated with large changes in subjective state and vice versa.
c) SUBJECTIVELY – most common strategy. ACT it the qualitative alteration in the overall pattern of mental functioning, such that the experiencer feels his consciousness is radically different from the way it functions ordinarily.
Problem: what is normal? (people will always differ)
What is altered in an ASC?
a) Consciousness has changed – when we then would study what has altered, it should reveal what consciousness itself is
Problem: It is not possible to measure consciousness in isolation from changes in perception, memory and other cognitive-emotional functions
b) ASC compared to a normal state due to a change to mental function: all mental functions are involved – ASC cannot be fully understood without understanding changes to the whole system
3 major variables that often change during ASC
Attention: changes along 2 dimensions:
a) Direction: can be directed inwards and outwards
b) Focus: broad vs narrow
Memory: changes linked to effects on thinking and memory
Arousal: high vs. low
Mapping states of consciousness using a multidimensional space
PHENOMENAL STATE SPACE (C-space)a multidimensional space in which a persons current state is defined by hundreds of variables
TART- 2 dimensions: 1. irrationality 2. ability to hallucinate Out of that, 3 major clusters occur: 1. Dreaming 2. Lucid dreaming 3. Ordinary consciousness All other positions cannot be occupied or are unstable. The occupied areas are discrete states of consciousness. To move into another region, one has to cross a forbidden zone
STEVEN LAUREY: 2 dimensions:
1. level of arousal: physiological wakefulness
2. awareness of environmental self: content of consciousness - requires a functionally integrated cortex with its subcortical loops
Most states and contents are positively correlated you need to be awake in order to be aware
AIM model by Allan Hobson: 3 dimensions
a) activation energy - similar to arousal (EEG)
b) input source: external or internal sources of input
c) ratio of amines (high when awake) to choline (high during REM)
States can be positioned in the brain-mind space
4-D MODEL:
a)Activation (low to high arousal)
b)Awareness span (narrow vs. broad)
c)Self-awareness (diminished to heightened)
d)Sensory dynamics (reduced to heightened sensation)
First step towards constructing a C-space
B-space
the space of functional brain-states
Challenge: create a mapping btw c-space (the space of states of consciousness) and B-space
meditation
Maintained voluntary shifts if attention
Interpretations of meditation (what does it do?)
- Meditation ist more than sleep or dozing: EEG profiles show difference, yet many meditators take mini naps
- Meditators learn to hold themselves at the transitional level btw sleep and wakefulness
- Meditations induce altered states of consciousness: sometimes it is the goal to reach different ASC
- Stimulation of rewards system: flood of dopamine - increased noradrenaline and then endorphins - opioids fade. Shifts can be seen with EEG and fMRI - d-ASC: term says that we should look for recognizable isomorphism between phenomenology and physiology
- d-ASC expresses the discrete state of brain networks from baseline.Idea is to correlate specific d-ASCs with changes in brain activity
- gradual change of neural structure: states reached by novice meditators may overlap with normal functioning, but advanced may reach unique states (increased synchronization etc)..
Mental illness
Some kinds of mental illness can induce ACT:
1. Mental illness is never solely mental: all psychological disorders involve feedback loops between thought patterns, emotions and moods, behaviors and bodily states
- Factors sustaining mental illness is the difference btw nature of experience when ill and when healthy. This can make it hard to remember states of consciousness other then the pathological one
Is illness itself an ACT? ACT is temporary, not permanent (psychosis yes, schizophrenia no)
Theories of sleep and dreaming
Jung: dreams are meaningful reflection of unconscious processes whose psychic importance is equal to that of the conscious mind itself
Activation synthesis hypothesis: dreaming results from rapid-eye-movement (REM) sleep physiology.
More recent theories: dreams fulfill an adaptive function related to emotion-regulation, learning and memory consolidation. reactivate and consolidate novel and individually relevant experiences
- biological defense mechanism: stimulate threatening situations
REM sleep
-definition and lesions
global high-frequency and low amplitude EEG activity, increased heart rate, respiratory activity, and muscle atonia - vivid dreams Lesions: a) forebrain: REM sleep without dreams b) Hindbrain: dreams without REM sleep
REM SLEEP phenomenological characteristics
NARRATIVE: Loose, bizarre narratives, related to current concerns, reflect interest, personality, and mood
- Dreamer is often uncertain about time, space and personal identities but has the subjective experience of being awake
SENSATION AND PERCEPTION: DREAMS share similarities with experiences during wakefulness:
- Visual and auditory sensations, physical activities, and language
- Tactile percepts, odors and tastes, as well as pleasure and pain are less commonly reported
Alterations from waking experiences: sensory distortions, misidentifications of characters and places, changes in the integration of time and location…
Emotions: most emotional content in that dreams (some emotions are more displayed than others)
Consciousness during REM
Dreams that occur during REM sleep show mostly aspects of primary but not secondary consciousness.
- Less metacognitive activity, reflective thoughts and volitional capabilities
Brain activity during REM
Large similarities with wakefulness
HYPERACTIVITY:Several brain regions become particular active during REM:
- Higher-order occipitotemporal visual association areas – vivid dreaming
- Motor regions, cerebellum, basal ganglia – motor content
- Pontine tegmentum, thalamus, basal forebrain, limbic and paralimbic structures – emotional processing
- Medial PFC, medial temporal lobe region, posterior cingulate cortex – memory and self-referential processing
- Default mode network
HYPOACTIVITY: Less active regions during REM sleep
- Right inferior parietal cortex – waking volition. Might allow the dreamer to participate in both first and third-person perspectives
- Executive regions – lack of insight, restricted volitional capacities, impaired metacognition
NREM SLEEP
Divided into three different stages (N1, N2, N3).
It is characterized by a global low-frequency and high amplitude EEG activity, slow and regular breathing and heart rate, as well as low blood pressure
Awakening from NREM yielded reports of dreaming as well (80-90%), but reports tend to be shorter.
- Sleep inertia – grogginess following abrupt awakening makes the evaluation of theses reports difficult
- dreams are often only recall of REM dreams or confabulations
BUT dreams also have been reported before occurrence of REM
Wakefulness, REM and NREM sleep are not necessarily mutually exclusive phenomena. Dreaming might be described along a continuum.
