PSY 326 SP14 001 Lecture 7Outline of Last Lecture Sleep and Learning- Geoffredina SpanoI. The effects of sleep deprivationII. What is sleep?a. Definition of sleepb. Why do we sleep?i. Evolutionii. Restiii. Homeostasisiv. Conservation of resourcesv. Miscellaneous biological processesvi. Memory consolidationc. Definition of ReactivationIII. The role of SWS and REM in the consolidation processa. The Active System Consolidation Hypothesis Diekelmann & Born (2010)b. Definition of SWS c. Definition of REMd. The Sequential HypothesisIV. Types of memoriesa. Long term memoryb. Definition of Procedural memories c. Definition of Declarative memories i. Definition of Semantic memoriesii. Definition of Episodic memoriesOutline of Current LectureEmotion, Memory, and The Brain – Ryan SmithI. Emotionsa. What are they caused by?b. What do they cause?II. Two dimensions of emotiona. Definition of Valenceb. Definition of ArousalIII. Valence a. Mood-congruent memory1. Definition of Mood-congruent b. Mood-dependent memoryi. Definition of Mood-dependent memoryIV. Arousal V. What can you still do without an amygdala?a.VI. Stress Hormonesi. Definition of HPACurrent LectureEmotion, Memory, and The Brain – Ryan SmithVII. Emotionsa. What are they caused by?i. Detecting a predator or enemyii. Detecting a threatening situationiii. Detecting a sexually attractive otheriv. Detecting family, friends, persons of authorityb. What do they cause?i. Changes in body stateii. Changes in attentioniii. Changes in cognitive/ decision making processesiv. Changes in memory storage and retrievalv. Ultimately, changes in behaviorVIII. Two dimensions of emotiona. Valence: This roughly amounts to “good” on one end and “bad” on the otherb. Arousal: This can be thought of a “calm/relaxing”on one end and “exciting/irritating intense” on the otherc. These dimensions may influence different aspects of memory in different waysIX. Valence – effects involve prefrontal cortexa. Mood-congruent memoryi. Emotional material is remembered more reliably in moods that match the emotional content of these memories1. If depressed, more memories of negative events will come to mind than positive2. Happy people remember more happy than sad information3. Sad people remember more sad than happy informationb. Mood-dependent memoryi. The likelihood of recalling an event is higher when encoding and recall moods match than when they are mismatched1. For example, if you were sad when you learned X, it will beeasier for you to remember X when you are sad again2. Caveats – Has to be genuine mood (i.e. it doesn’t work if you’re pretending to be happy)3. The effect is stronger for memories of mental operations (thinking, reasoning, imagining) than memories of externalperceptions.X. Arousal – effects involve the amygdalaa. Retention advantages for emotionally arousing words relative to neutral words are greater when memory is tested after long (1h to 1 day) than after short (immediate) delay intervals.b. Such observations provide evidence that emotional arousal benefits memory in part by facilitating consolidation processes, which take time toemergec. Temporal lobectomy patients do not show enhanced arousal-mediated memory consolidation but instead show parallel forgetting rates for arousing and neutral words from immediate to 1h retention intervalsd. Urbach-Wiethe syndrome patients (i.e. no amygdala) also show impairments in long term (1h to 1 month) recall or recognition of emotional words, pictures and storiese. Conclusion: Long-term consolidation advantage for emotional memory requires amygdala. Emotional arousal biases attention & what gets into memory in the first place.XI. What can you still do without an amygdala?a. Patients with amygdala lesions do preferentially remember words that areaffectively valent but low in arousal relative to neutral ones, as well as neutral words encoded in emotional sentence contexts relative to neutral contextsb. This may recruit valence-specific PFC resourcesc. Arousal rather than valence is the crucial factor in engaging the amygdala during emotional memory tasksXII. Stress Hormonesa. The amygdala can activate the hypothalamusi. HPA: Hypothalamic-pituitary-adrenal axis b. Results in release of adrenaline and cortisol in bloodi. These can feed back into the brain (directly or indirectly) and affect brain processesii. Specifically can affect amygdala, hippocampus, and prefrontal cortexc. Overall, stress hormones tend to enhance memory functioni. Unless levels are too highii. Inverted U-shaped functiond. So amygdala induces arousal (in part) by triggering stress hormones, and these in turn alter memory