PSYC 444 Lecture Notes - Lecture 1: Parasomnia, Neuroplasticity, Memory Consolidation
14 May 2018
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PSYC 444 – LECTURE 1
WHAT IS SLEEP?
Behavioral view: inactivity
Sleep scientist view: polysomnographic markers
Subjective experience: feeling of being asleep, dreaming; parasomnias
It is difficult to distinguish a sleeping person and a person in a coma as the physical indicators are the same.
• Must use electrodes and brain patterns to infer stage of sleep
• Even if not dreaming, there is the subjective experience of having slept; it is different from being in a coma or being knocked out
THEME: DYNAMIC BALANCE
Homeostasis: organism needs to maintain internal stability in face of environmental perturbations
Dynamic balance: system looks stable and unchanging but it is actually constantly adapting to changes in both its internal states and
environment
Themes: activity, cyclic, waking, amount and self-world
Organisms must sleep in order to survive, be cognitively available and to regenerate. However, this must be balanced with vigilance when
awake. Thus, demands from the world and bodily needs must be in a state of equilibrium.
WHO STUDIES SLEEP?
Psychologists, neurologists, neuroscientists, clinicians and philosophers
• Philosophers study sleep and consciousness
Every physiological or psychological function is related to sleep to some extent.
• However, despite ubiquity of sleep, there are very little resources available to the general population
• Very few are trained in sleep therapy, and sleeping pills are not a good solution
HISTORY OF SLEEP RESEARCH
As far as I ko, the oly reaso e eed to sleep that is really, really solid is eause e get sleepy” (DT Max)
• An experiment that kept rats awake demonstrated that without sleep, animals die
If sleep does’t sere a asolutely ital futio, it is the iggest istake the eolutioary proess has eer ade” (Alan Rechtschaffen)
• We are completely vulnerable while asleep. Thus, there must be an evolutionary reason for sleeping
There is no single accept theory on sleep
Homeostatic theory: life is energy-demanding, and sleep allows us to conserve energy
• Sleep is involved in thermoregulation
Cognitive theory: sleep is the price for brain plasticity
• Downscaling synaptic strength in sleep allows for more cognitive function in wake
• Sleep for memory consolidation and optimal emotion and attention functioning
BASIC NOTIONS
Sleep is ubiquitous
All animals sleep: Unicellular organisms, insects, amphibians, fish, birds and mammals
• Even unicellular organisms without a nervous system show patterns of rest
• Unclear whether plants have patterns of sleep
SLEEP AND CONSCIOUSNESS
It is difficult to define the relationship between sleep and consciousness
• Many taxonomies have been proposed
• What’s the differee etee soeoe asleep, uosious or oatose?
Main problem: definition of consciousness varies widely between researchers in the same domain, and especially between domains
THREE CLASSIC STATES OF CONSCIOUSNESS/AWARENESS
1. Wake
• Awareness of self and environment
• Fast reflexes
• Mental activity is spontaneous and intentional
2. Deep sleep
• Slow wave, delta, non-rapid-eye-movement (NREM) sleep
• Dreamless
find more resources at oneclass.com
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Document Summary
Subjective experience: feeling of being asleep, dreaming; parasomnias. It is difficult to distinguish a sleeping person and a person in a coma as the physical indicators are the same: must use electrodes and brain patterns to infer stage of sleep. Even if not dreaming, there is the subjective experience of having slept; it is different from being in a coma or being knocked out. Homeostasis: organism needs to maintain internal stability in face of environmental perturbations. Dynamic balance: system looks stable and unchanging but it is actually constantly adapting to changes in both its internal states and environment. Organisms must sleep in order to survive, be cognitively available and to regenerate. However, this must be balanced with vigilance when awake. Thus, demands from the world and bodily needs must be in a state of equilibrium. Every physiological or psychological function is related to sleep to some extent.
