psychology 101 chapter 4

Active attention, multitasking, cocktail party effect

• assessed via continuous performance task

• maintain focus on one stimulus/task

• interrupts focused attention…humans are not good at this…rapidly shift between 2 stimuli 

• even though there’s loads of convos around you…you can selectively ignore others and selectively pay attention to who you are speaking with

how long can humans sustain active attention v. passive attention?

• 15 min

• 1 hour 15 min

inattentional blindness

• failure to notice something clearly perceivable b/c attention is directed elsewhere 

ex: Simons + Chabris 1999…gorilla on screen…only 50% notice it…

change blindness 

• failure to notice CHANGES in environment b/c attention is directed elsewhere 

• Simons & Levin 1998…on campus, someone would approach asking for directions, person asking would switch behind plywood…50% didn’t notice the switch b/c they were paying attention to the map not the person 

why isn’t sleep the same as unconsciousness?

• it is an altered state of consciousness

• we are still aware of ourselves and our environment

• less aware but still vaguely aware…don’t fall out of bed b/c you are aware of the bounds of your bed…aware of external environment

• aware of internal environment…dont pee ourselves

what are the 4 theories of why we sleep?

1. rest

• not the only purpose b/c we should be able to get the same result from lying quietly in bed with eyes open…conserve same energy and digest same energy

1. protection from the dark

• ancestors evolved to sleep when its dark…survival function…no one could see when it became dark…animals can…protection from predators

1. to consolidate memories

• when you get a good night of sleep, you remember things better the next day…if you wake someone up during certain portions of sleep they will be thinking about something that happened that day

1. to get rid of unused brain pathways

• new synapses in the central nervous system…having too many synapses is not better…more maze like it becomes…use it or lose it policy…prune synapses not being used…makes synapses that you use stronger and clearer…the longer you stay awake the more synapses develop

circadian rhythm

• internal clock…synchronized to environment

• adheres to a 24 hour cycle

• process of sleep v wakefulness processes in this time

light impact on circadian rhythm

• light travels to optic nerve to hypothalamus which reh homeostasis…SCN part of hypothalamus(suprachiasmatic nucleus) which signals the pineal gland to inhibit melatonin production

• melatonin is a hormone that causes sleepiness

• when it gets darker…inhibition stops and more melatonin is released 

sleep homeostat

• keeps track of how much you slept

• achieve sleep homeostasis…balance between sleep and wakefulness…different people need different amounts

• hypothetical…not mapped onto physiological process

• if you tip too far towards wakefulness…body will make it hard for you to stay awake

sleep debt 

• if you don’t make up the amount of hours your body needs according to your sleep homeostat 

• can only be made up to an extent 

• if its consistent debt builds up and becomes impossible to pay back causing issues 

1. poorer cognitive performance 

• cant think as well…more errors…slower rxn times

• cognitive tasks given…half kept awake for 24 hours…other half drunk…drunks performed better

1. increased body fat storage 

• sleep deprivation releases stress hormone cortisol…makes us hungry…encourages body fat storage…heart disease 

1. immune system suppression 

• harder time fighting viral infections 

1. increased risk for depression 

• 71% increase 

stages of sleep

1 : vaguely aware, hallucinations

2: light, unaware

3: deep sleep

REM: Rapid Eye Movement…dreams…increased HR, BR…motor neurons are inhibited (our body is still)…prone to sleep paralysis is you wake up abruptly during this part of the cycle

During what stage are we half awake/half asleep?

• stage 1

• still taking in new info from environment and forming new memories

During what stage are we prone to hallucinations & unusual sensations?

1 

During what stage do we experience sleep spindles & k-complexes?

2

• rapid change in short time

• large increase of voltage, large decrease, level out

both rep brain working to keep asleep despite outside

During what stage are we fully asleep, but still easy to wake up?

2

During which stage do we think about events from our day?

• 3

During what stage do we dream?

REM…always dream during rem even if we don’t remember it

During what stage is most of our body paralyzed?

REM

What do we commonly dream about?

• things we do in real life

• bad stuff happening…embarrassing or traumas re-lived

• outside stimuli

ex:waking up w/ water during rem → more likely to dream about water

• sex (3-50% of dream content)

Lucid dreaming

• awareness that you are dreaming and the ability to control these dreams

• dream journal….look for patterns…oddities…reality check when awak…realize youre in a dream…stand in one spot…look at feet…spin in a circle

4 theories of why we dream…

1. symbolic meaning 

2. brains making sense of random neural activity 

…not scientific 

1. cognitive perspective says that it is for filing away memories…enhance existing ones…less REM…poorer recall 

2. neurosci perspective says that is provides stimulation…promotes growth of neural pathways…areas of brain that are responsible for an activity in real life are activated during sleep when you are doing that activity in sleep…

What is the difference between: concentrative meditation & mindfulness meditation?

• focus on 1 set of stimulus…ex: breathing in and out…mental image like a beach or forest…mantra like ommm

• allow thoughts to flow freely…pay attention to thoughts BUT don’t react…let it go…don’t try to solve the problem

can we say that meditation causes any of its associated benefits?

• no, studies are correlational

• not sure how and why meditation has these impacts

Can everyone be hypnotized?

• no 

• depends on susceptibility

• good focused attention 

• rich imagination 

• easily absorbed in activities  

• 5-10% can’t be hypnotized at all 

hypnosis

• heightened state of suggestibility

Can hypnosis enhance recall of the past?

• not supported by research

• not everything is stored in mems…hypnosis cant make us remember if we never stored it

• if a hypnotist asks a leading question it can be incorporated into memory as something that actually happened

can it force you to act against your will? 

• no 

is it an effective form of therapy?

• not sure how it works

• possible placebo affect…equal treatment of subjects

• report getting better…self fulfilling prophecy…beliefs cause to change behavior to make something become true

• belief in hypnosis might be what makes it affective