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COGNITIVE SCIENCE 17 Final review. COGNITIVE SCIENCE 17 Final review. Biological rhythms (periodic physiological fluctuations). Types of rhythms Ultradian (Basic Rest-Activity Cycle) p294 Circadian (sleep-wake cycle) p319-326 Infradian (menstrual cycle)
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COGNITIVE SCIENCE 17 Final review
COGNITIVE SCIENCE 17 Final review
Biological rhythms (periodic physiological fluctuations) • Types of rhythms • Ultradian (Basic Rest-Activity Cycle) p294 • Circadian (sleep-wake cycle)p319-326 • Infradian (menstrual cycle) • Circannual (annual breeding cycles) • All rhythms allow us to time events • and anticipate change!
With Zeitgeber See p319.
Suprachiasmatic nucleus (SCN) is master pacemaker • Activity in suprachiasmatic nucleus correlates with circadian rhythms • Lesions of suprachiasmatic nucleus abolish free-running rhythms • Isolated suprachiasmatic nucleus continues to cycle • Transplanted suprachiasmatic nucleus imparts rhythm of the donor on the host p 320-324
Timing Photoreceptors • The existence of photoreceptors not specialized for visual functioning • Regulate photoperiodism (sensitivity to length of night) • Entrainment of circadian rhythms • Melanopsin-containing cells found in monkey retinal ganglion cell layer (Provencio et al., 2000) • Most likely comprise the retinohypothalamic tract • Sensitive to wavelengths in the 484-500 nm (blue light)
Minutes of Stage 4 and REM Decreasing Stage 4 25 20 15 Increasing REM 10 5 0 1 2 5 6 7 8 3 4 Hours of sleep Typical Nightly Sleep Stages
Troubled Sleep… • Night terrors (pavor nocturnus) • Nightmares • Sleep deprivation p301 • Narcolepsy p297-299
Sleep stages Awake 1 2 3 REM 4 0 1 2 3 4 5 6 7 Hours of sleep Night Terrors and Nightmares • Night Terrors (p299) • occur within 2 or 3 hours of falling asleep, usually during Stage 4 • high arousal- appearance of being terrified • Nightmares (p295) • occur towards morning • during REM sleep
What is a BCI? • Brain-Computer Interface • Enables communication without movement or motor control. • Some target patients cannot use any interface requiring voluntary movement.
What is a BCI? One of the first uses was designed for Locked-in Syndrome, a condition marked by total immobilization yet complete consciousness. This can follow stroke, injury or disease (MS) which damages the ventral pons. [One notable patient, journalist Jean-Dominique Bauby, dictated his memoir using a system of blinking his left eye to chose a letter. The Diving Bell and the Butterfly.]
What is a BCI? Most BCIs translate your brain’s electrical activity (EEGs) into messages or commands. Performing mental tasks produces electrical activity detectable with electrode caps.
What is a BCI? • BCIs may be: • Non-invasive (usually EEG) • Invasive • ECoG (surface of cortex) • depth recording (in brain)
How do EEGs work? • Newer EEG recording systems: • Require less or no prep time and skill • Require less or no gel • Require fewer electrodes • Are more portable • Handle artifacts better • Are wireless • Are cheaper Field recording systems from Quasar, Advanced Brain Monitoring, and Pineda et al (2003).
Components • How do BCIs work? • General Schematic • P300 BCI • Mu BCI • Other BCIs
Components • All BCIs have at least four components: • Signal Acquisition • Feature Extraction • Translation Algorithm • Operating Environment The Four BCI Components (Wolpaw et al., 2002; Allison et al., 2007)
Selective attention: SSVEP Steady state visual evoked potential (SSVEP) Herrmann et al, Exp. Brain Research 2001
SSVEP 6 Hz 15 Hz Steady state visual evoked potential (SSVEP) BCI (Kelly et al., 2005)
Emerging User Goals • Replacing conventional interfaces for disabled users in conventional settings.(BOTHfor communication and rehab). • Replacing conventional interfaces for conventional users in specificsettings. • Supplementing conventional interfaces.
BCI Autism Rehabilitation UCSDnews.ucsd.edu
Emotions (Chapter 11) Responses of the whole organism, involving... • physiological arousal (autonomic/hormonal) • expressive behaviors (behavioral) • conscious experience (cognitive)
Basic Emotions--presumed to be hard wired and physiologically distinctive Are Emotions Universal? • Joy • Surprise • Sadness • Anger • Disgust • Fear Pg 380
Expressing Emotion • Culturally universal expressions
Sight of oncoming car (perception of stimulus) Pounding heart (arousal) Fear (emotion) James-Lange Theory of Emotion Pg 390 • Experience of emotion is awareness of physiological responses to emotion-arousing stimuli
Pounding heart (arousal) Sight of oncoming car (perception of stimulus) Fear (emotion) Cannon-Bard Theory of Emotion • Emotion-arousing stimuli simultaneously trigger: • physiological responses • subjective experience of emotion
Pounding heart (arousal) Sight of oncoming car (perception of stimulus) Fear (emotion) Cognitive label “I’m afraid” Schacter’s Two-Factor Theory of Emotion • To experience emotion one must: • be physically aroused • cognitively label the arousal
Autonomic nervous system controls physiological arousal Sympathetic division (arousing) Pupils dilate Decreases Perspires Increases Accelerates Inhibits Secrete stress hormones Parasympathetic division (calming) Pupils contract Increases Dries Decreases Slows Activates Decreases secretion of stress hormones EYES SALIVATION SKIN RESPIRATION HEART DIGESTION ADRENAL GLANDS Physical Arousal
Performance level Difficult tasks Easy tasks Low Arousal High Arousal and Performance • Performance peaks at lower levels of arousal for difficult tasks, and at higher levels for easy or well-learned tasks
Amygdala is deep within the most elemental parts of the brain.
Cognition and Emotion The brain’s shortcut for emotions
Brain Structures That Mediate Emotion • Hypothalamus • Limbic System • limbic cortex • amygdala • Brainstem
Hypothalamus • What does it do? • Integration of emotional responses • Forebrain, brain stem, spinal cord • Sexual response • Endocrine responses • neurosecretory • oxytocin, vasopressin
Hypothalamus • How do we know that it integrates emotions and behaviors? • Ablation studies • Stimulation studies • Primary Emotions: Fear and Anger
Ablation Studies • Cats • Remove cerebral hemispheres: rage • Remove hemispheres and hypothalamus: no rage
Stimulation Studies on Cats • Lateral hypothalamic stimulation: rage, attack • Other areas: defensive, fear
Hypothalamus:Routes of information • Input from: cortex (relatively unprocessed) • Output to Reticular Formation
Brainstem: Reticular Formation • Brainstem web • 100+ cell groups • Controls • sleep-wake rhythm • Arousal • Attention
Limbic System • Link between higher cortical activity and the “lower” systems that control emotional behavior • Limbic Lobe • Deep lying structures • amygdala • hippocampus • mamillary bodies
Limbic Lobe • What is it? • Cingulate gyrus • Parahippocampal gyrus • Where is it? • Encircles the upper brain stem • around corpus callosum
Limbic System • What does it do? • Integrates information from cortical association areas • How do we know this? • Kluver - Bucy Syndrome
Kluver - Bucy Syndrome • Removal of temporal lobe in animals • Pre-op • aggressive, raging • Post-op • docile, orally fixated, increased sexual and compulsive behaviors
Kluver- Bucy Syndrome in Humans • Severe temporal lobe damage • tumors, surgery, trauma • Visual Agnosia • Apathy/ placidity • Hyperorality • Disturbance in sexual function (hypersexuality) • Dementia, aphasia, amnesia
Amygdala • What is it? • Nuclear mass • Where is it? • Buried in the white matter of the temporal lobe, in front of the hippocampus
Amygdala: What Does It Do? • Connects to: • olfactory bulb and cortex • brainstem and hypothalamus • cortical sensory association areas • “Emotional Association Area”
Amygdala Conditioned emotional response: Neutral stimulus can be associated with aversive stimulus, resulting in same autonomic, behavioral and hormonal responses. Pg. 366
Amygdala and Learned Emotions • Learned fear: rats and classical conditioning • Conditioned emotional response • Abolish fear response • cut central nucleus from amygdala OR • infuse NMDA antagonist into amygdala during learning
Memory The ability to retain learned information and knowledge of past events and experiences and to be able to retrieve that information. Organization of experience….what would you do without it? Learn ---- Retain ---- Retrieve Encoding ---- Maintenance ---- Retrieval