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Introduction to Psychology

Myers PSYCHOLOGY (7th Ed)Chapter 3 States of Consciousness

James A. McCubbin, PhDClemson University

Worth Publishers

1Waking ConsciousnessConsciousnessour awareness of ourselves and our environments

2What is the dual processing being revealed bytodays cognitive neuroscience?

3Dual Processing: The Two-Track Mind

Blindsight

4Subliminal & blindsight processing pathway

Fig. 1. Colliculo-pulvinar secondary visual pathway. Activation maps showsignificant BOLD signal in the left superior colliculus (SC) and left pulvinaras a result of the ROI analysis ( P b 0.05 small volume corrected). Coloredt-bars are provided to indicate the level of significance of observed BOLDactivation. The observed activity in these regions to undetected fear signalssuggest a crude relay of stimulus information from the retina to the superiorcolliculus, which conveys stimulus information to the pulvinar in theposterior thalamus. Such information is of a lower spatial resolution thanthe dominant visual processing stream involving the lateral geniculatenucleus in the thalamus and the striate cortex, but may facilitate somedegree of processing when this primary pathway is unavailable, such as insubliminal processing or blindsight.5Threat-related signal processing (fight/flight response)

Fig. 2. Brainstem (locus coeruleus) and amygdalae. Activation maps show significant BOLD activity in the bilateral amygdalae (A) and the left brainstem,encompassing the locus coeruleus (LC). This was a result of the ROI analysis ( P b 0.05 small volume corrected). Amygdala activations are presented at a P =0.1 threshold for illustration purposes only. Colored t-bars are provided to indicate level of significance of observed BOLD activation. Evidence suggests thatthe pulvinar is functionally connected with the amygdala (A), which may facilitate rapid processing to the amygdala in response to threat-related signals(Morris et al., 1998). Such signals may initiate the fight/flight mechanisms of the brainstem, including the involvement of the locus coeruleus (LC) from whichthe ascending noradrenergic pathways are triggered in times of stress or in response to significant stimuli (Aston-Jones et al., 1996).6Brainstem activated neural alarm system (alerting/orienting)

Fig. 3. Frontal and temporal regions. Activation maps shown here are as a result of the whole brain analysis ( P b 0.001 uncorrected). Only the key regions aredisplayed. Colored t-bars are provided to indicate level of significance of observed BOLD activation. The brainstem (primarily the locus coeruleus) caninnervate diffuse regions of the cortex and subcortical structures, including amygdala (A), via ascending collateral noradrenergic pathways. Such a broadinnervation of the cortex, including frontal (anterior cingulate, inferior, superior frontal gyri, premotor, cingulate and medial prefrontal cortex), temporal(superior, middle, and inferior temporal gyri), and somatosensory [insula (presented at P = 0.01 for illustration purposes only), post central gyrus] regions, wasobserved to undetected fear signals in this study. This may resemble a neural alarm system, incorporating aspects of alerting and orienting, to most efficientlyprocess threat-related stimuli.7Brainstem-amygdala-cortical alarm system for subliminal signals of fear

Fig. 4. Brainstemamygdalacortical dalarmT system for subliminal signals of fear: a heuristic model. Figs. 13 demonstrate possible interconnections betweenactivated brain regions in response to undetected signals of fear, as observed in this study, based on substantial neuroscientific evidence (as outlined in thediscussion). We propose that these systems are integrated to form the neural basis of an initial alarm mechanism, offset to provide an evolutionary adaptivemechanism to respond optimally, with heightened vigilance, to threat-related stimuli in the environment. The fear faces in this study are presented briefly,followed immediately by a superimposed but spatially offset neutral face mask, in a backward masking procedure. The fear face is thus consciously undetected.Crude sensory information most likely reaches the amygdala (A) via a colliculo (SC)pulvinar pathway, bypassing the primary visual cortex. Activationobserved within the anterior midbrain region of the brainstem, which encompasses the locus coeruleus (LC), suggests that these regions may play an importantrole in initiating basic fight/flight responses. The brainstem can provide broad excitatory collateral innervation of the cortex, including anterior cingulate andother frontaltemporal structures, to facilitate an increase in the alert state.8Selective AttentionOur conscious awareness processes only a small part of all that we experience. We intuitively make use of the information we are not consciously aware of. 9Preview Question 2: How much information do we consciously attend to at once?

Inattentional BlindnessInattentional blindness refers to the inability to see an object or a person in our midst. Simons & Chabris (1999) showed that half of the observers failed to see the gorilla-suited assistant in a ball passing game.

Daniel Simons, University of Illinois10Change BlindnessChange blindness is a form of inattentional blindness in which two-thirds of individuals giving directions failed to notice a change in the individual asking for directions.

1998 Psychonomic Society Inc. Image provided courtesy of Daniel J. Simmons.11

Byflipping the jars after putting the lids backon, the researchers actually induced peopleto resample their nonchosen jam. Yet,even when asked whether they noticed anythingodd, most tasters were choice blind.Even when given markedly different jams,they usually failed to notice the switch.12Biological Rhythms and SleepCircadian Rhythms occur on a 24-hour cycle and include sleep and wakefulness. Termed our biological clock, it can be altered by artificial light.Light triggers the suprachiasmatic nucleus to decrease(morning) melatonin from the pineal glandand increase (evening) it at nightfall.

13Preview Question 3: How do our biological rhythms influence our daily functioning and our sleep and dreams?Sleep & DreamsSleep the irresistible tempter to whom we inevitably succumb.Mysteries about sleep and dreams have just startedunraveling in sleep laboratories around the world.

Sleep and DreamsBiological Rhythmsperiodic physiological fluctuationsCircadian Rhythm the biological clockregular bodily rhythms that occur on a 24-hour cycle, such as of wakefulness and body temperature

Premenstrual SyndromePremenstrual Menstrual IntermenstrualMenstrual phaseActualRecalled mood321Negative moodscoreRecalled mood isworse thanearlier reported

Sleep and DreamsREM (Rapid Eye Movement) Sleep recurring sleep stage vivid dreamsparadoxical sleep muscles are generally relaxed, but other body systems are activeSleepperiodic, natural, reversible loss of consciousness

Sleep and DreamsMeasuring sleep activity

Brain Waves and Sleep StagesAlpha Wavesslow waves of a relaxed, awake brainDelta Waveslarge, slow waves of deep sleep Hallucinationsfalse sensory experiences

Stages in a Typical Nights Sleep012345674321SleepstagesAwakeHours of sleepREM

Theories of sleepSleep protectsSleep helps us recuperate (repair)Sleep helps restore and rebuild memoriesSleep feeds creative thinkingSleep supports growth

Stages in a Typical Nights SleepHours of sleepMinutesof Stage 4 and REM123456780101520255Decreasing Stage 4Increasing REM

90-Minute Cycles During SleepWith each 90-minute cycle, stage 4 sleep decreases and the duration of REM sleep increases.

Why do we sleep?We spend one-third of our lives sleeping.

If an individual remains awake for several days, immune function and concentration deteriorates and the risk of accidents increases.

Jose Luis Pelaez, Inc./ Corbis24Preview Question 5: How does sleep loss affect us? Sleep HoursBat -> 20 hoursBaby -> 16 hoursCat -> 12Dolphin -> 10 hoursAdult -> 8 hoursCow -> 4 hoursGiraffe -> 2 hoursSleep TheoriesSleep Protects: Sleeping in the darkness when predators loomed about kept our ancestors out of harms way.Sleep Helps us Recover: Sleep helps restore and repair brain tissue.Sleep Helps us Remember: Sleep restores and rebuilds our fading memories.Sleep may play a role in the growth process: During sleep, the pituitary gland releases growth hormone. Older people release less of this hormone and sleep less.26Preview Question 6: What is sleeps function?Children are most prone to:

Night terrors: The sudden arousal from sleep with intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) which occur during Stage 4 sleep.Sleepwalking: A Stage 4 disorder which is usually harmless and unrecalled the next day.Sleeptalking: A condition that runs in families, like sleepwalking.

Sleep DisordersNight Terrors and NightmaresNight Terrorsoccur within 2 or 3 hours of falling asleep, usually during Stage 4high arousal-- appearance of being terrified012345674321SleepstagesAwakeHours of sleepREM

Sleep DisordersInsomniapersistent problems in falling or staying asleepNarcolepsyuncontrollable sleep attacksSleep Apneatemporary cessation of breathingmomentary reawakenings

Sleep DeprivationEffects of Sleep Lossfatigueimpaired concentrationdepressed immune systemgreater vulnerability to accidents

Sleep Deprivation2,4002,7002,6002,5002,800Spring time change(hour sleep loss)3,6004,20040003,800Fall time change(hour sleep gained)Less sleep,more accidentsMore sleep,fewer accidentsMonday before time changeMonday after time changeAccident frequency

Dreams: FreudDreamssequence of images, emotions, and thoughts passing through a sleeping persons m