Memory Encoding PDF

Memory Encoding 02 February 2024 12:08 Main Ideas Notes Notes Notes Key Brain Regions fMRI Meta-Analysis: Identified consistent activity in ventrolateral PFC, dorsolateral PFC, posterior parietal cortex, MTL, and fusiform cortex. Predictive Regions: Some regions indicate memory success, others failu...

Memory Encoding 02 February 2024 12:08 Main Ideas Notes Notes Notes Key Brain Regions fMRI Meta-Analysis: Identified consistent activity in ventrolateral PFC, dorsolateral PFC, posterior parietal cortex, MTL, and fusiform cortex. Predictive Regions: Some regions indicate memory success, others failure. Semantic Task Electrical Activity: Analyzed during cue intervals, predicting later recollection. Activity Characteristics: Negative, maximal over frontal scalp sites, and dissociable from post -word onset activity. Ventrolateral Prefrontal Cortex Role in Encoding: Engaged in deep encoding tasks with verbal material. Function: Processes goal-relevant item information, particularly higher -level language features. Implication Pre-Stimulus Activity: Highlighted as important for encoding. Encoding Success and Failure: Suggested pre -stimulus activity could influence both. Dorsolateral Prefrontal Cortex Function in Encoding: Involved in tasks requiring working memory or inter -item processing. Executive Control: Plays a role in managing encoding processes. Why Important? Theory Alteration: Changes theoretical perspectives on encoding. Potential Applications: Suggests possibilities for enhancing memory through training. Posterior Parietal Cortex Unexpected Role: Traditionally linked to attention and motor planning, not memory. Amnesia and Alzheimer's: Studies showing deficits and metabolic changes in this region. Since Then? Research Progress: Over 120 publications since 2006, exploring pre -stimulus influences on memory. Functional Role: Attention? Dorsal Parietal Cortex: Associated with memory success and goal -directed attention. Ventral Parietal Cortex: Linked to memory failure and attention to irrelevant information. Main Findings Influence of Brain Activity: Activity a few minutes to milliseconds before an event can impact encoding. Associated Brain Regions: Primarily the medial temporal lobe (MTL) and amygdala. Task Sensitivity: More pronounced in deep encoding tasks, especially with emotional or rewarded events. What was Damaged in H.M. Surgical Removal: About 5 cm of tissue removed bilaterally, including anterior hippocampus, posterior atrophy, surrounding cortex, and amygdala. Assessment Methods: Estimated by surgeon, confirmed by MRI and post-mortem studies. Frontoparietal Attention Network Interpretation: Based on known functions of the posterior parietal cortex in attention research. Attention Types: Dorsal network for top -down (goal-directed) attention, ventral for bottom -up (stimulus-driven) attention. Low/High Reward Memory and Reward: Study of intentional memorization influenced by potential monetary rewards. Recognition Memory: Assessed how cues about rewards affected memory retention. The Hippocampus is Crucial H.M.'s Case Analysis: Shows specific memory deficits linked to hippocampal damage. Further Research: Studies with other patients and animals affirm the hippocampus's critical role in memory. Medial Temporal Lobe Consistency in Studies: Varied findings, except in spatial navigation tasks. Functional Roles: Proposed roles include element binding, scene construction, cognitive mapping, novelty detection, and consolidation. Pre-Stimulus Activity Prediction of Success: Activity before word onset indicated encoding success, especially in high -reward conditions. Strategic Encoding: Suggests a voluntary state to aid encoding. Nature of the Deficit Explicit Episodic Memory: Severely impaired in H.M. and similar patients. Controversy: Exact nature of deficits remains debated. Selective Impairments: Highlight how different brain regions affect memory. Which Regions are Essential? Confirmed: Ventrolateral PFC and dorsolateral PFC (TMS evidence), MTL (lesion evidence). Possible: Posterior parietal cortex (mixed evidence). The Search for the Engram Engram: Concept of a physical trace of memory in the brain. Lashley (1920s): Studied memory deficits and brain lesions; suggested brain's equipotentiality for memory. Penfield (1940s): Used electrical stimulation of the temporal lobe, eliciting recall experiences, indicating localization of function. Breakthrough (1950s) Medical Cases: Patients with medial temporal lobe (MTL) removal exhibited specific memory issues. Bilateral MTL Resection: Led to anterograde amnesia, highlighting the MTL's role in memory. Cultural References: Films like 'Memento' explore these memory concepts. Living Without a Memory Case Study: 'Sally' from Gold Star Productions, a portrayal of memory impairment. Focus on understanding how certain memory types are affected by such conditions. Henry Gustav Molaison (H.M.) H.M. (1926-2008): A significant patient in amnesia studies. Brain Examination: Post-mortem analysis of 2401 brain slices for detailed study. Taxonomy of Memory Memory Types: Exploration of various memory forms in cognitive neuroscience. Categorization: Helps in understanding and differentiating memory processes and impairments. Role of Cognitive Neuroscience Memory Analysis: Uses amnesic patients to understand memory types and brain regions. Challenges: Difficulty in isolating memory stages and understanding normal memory through pathological cases. Memory Processes: Focus on encoding, storage, and retrieval. How to Study Memory Encoding 'Dm' Approach: Uses the 'Difference due to Memory' method in cognitive neuroscience. Memory Encoding: Involves assessing differences in brain responses to remembered and forgotten information. Dm Approach Encoding and Recall: Studies how brain activity during encoding predicts later memory performance. Techniques: Uses comparisons of remembered vs. forgotten words or images in tests. Is There Only One Encoding System in Our Brain? Central Question: Investigates whether the same brain regions are always involved in effective encoding. Main Results Pre-Stimulus and Emotion: Negative pictures showed a link between pre -stimulus activity and encoding success. Variability: Indicates complexity in how emotions influence memory encoding. Manipulations at Study Encoding Task Variations: Different types of tasks and materials lead to qualitative differences in encoding -related activity. Anticipation May Be Used to Regulate Emotions Regulatory Mechanism: Suggests anticipation plays a role in emotional regulation related to memory encoding. Manipulations at Test Test Variations: Encoding -related activity differs based on how memory is later probed, e.g., spoken word or picture probes. Conclusions Multiple Encoding Systems: Brain employs various systems for memory encoding. Key Brain Regions: Prefrontal, parietal, and medial temporal lobe regions are critical. Role of Pre-Stimulus Activity: Contributes to encoding, but its exact function remains unclear; possibilities include neural pre activation, active preparation, or cognitive control. A Model of Memory Encoding Multiple Systems: The brain employs various encoding systems. Feature Overlap: Encoding -related activity depends on the overlap of features between study and test phases. When Does Encoding-Related Brain Activity Occur? Timing of Activity: Investigates the exact moment when encoding -related activity in the brain takes place. Wagner et al., (1998) Pioneering Study: First to use Dm approach with event-related fMRI. Deep Encoding: Examined how encoding tasks (abstract/concrete word judgment) affected memory. Assumption Traditional Belief: Cognitive neuroscience has assumed that memory is best explained by activity immediately following an event. Dm Effects Brain Activity Correlation: Activity in left prefrontal, parahippocampal, and fusiform regions linked to confident memory recall. Further Studies: Reference to Paller & Wagner (2002) for in-depth understanding. Event-Elicited Activity Common Focus: Most studies concentrate on this activity type. EEG Findings: Show encoding -related activity from around 200 ms after event onset. Later Studies Techniques Used: Employed fMRI, EEG, MEG, TMS, and optical imaging. Research Expansion: Hundreds of studies exploring encoding-related brain activity. Summary PSYC0031 Cognitive Neuroscience Page 1 Emotional Events Emotional Impact: Incidental encoding of emotional pictures and its effects on memory. Gender Differences: Notable encoding success for negative pictures, especially in women. A Seminal Finding Incidental Encoding Study: Investigated electrical brain activity and its prediction of later recollection. Key Focus: EEG studies examining the cue interval during study phase and its impact on memory. Key Co 1. Engram to unde 2. Lashley rather t involve 3. Penfiel brain a 4. Medial resectio 5. Henry G the hipp 6. Hippoc convert 7. Explicit severe 8. Taxono better u 9. Cogniti unders 10. 'Dm' Ap brain re 11. Wagne unders 12. Key Bra cortex, 13. Frontop recallin up). 14. Medial scene c 15. Encodi unders 16. Event-E unders 17. Pre-Sti into me 18. Encodi influenc Notes oncepts/Theories/Models, etc m: A theoretical construct representing the physical trace or imprint of a memory in the brain. The concept is central erstanding how memories are stored and retrieved. y's Equipotentiality Hypothesis: Proposed by Karl Lashley, suggesting that memory is distributed across the brain than localized in one area. This theory has been refined with modern neuroscience showing specific brain regions d in memory. d's Electrical Stimulation Studies: Wilder Penfield's work suggested that memories could be localized in certain reas, especially in the temporal lobes, contradicting Lashley's theory to some extent. Temporal Lobe's Role in Memory: Research in the 1950s, especially involving patients with medial temporal lobe ons, highlighted the crucial role of this brain region in memory, particularly in forming new memories. Gustav Molaison (H.M.): H.M.'s case was pivotal in understanding memory. His surgery, which removed parts of pocampus, provided key insights into how specific brain areas contribute to memory processes. ampus: Essential for forming new explicit memories. H.M.'s case demonstrated that the hippocampus is crucial for ting short-term memories into long-term memories. t Episodic Memory: Refers to the conscious recollection of personal experiences and specific events. H.M. showed impairments in this type of memory. omy of Memory: This involves categorizing different types of memory (e.g., explicit, implicit, episodic, semantic) to understand their unique characteristics and underlying brain mechanisms. ive Neuroscience of Memory: This field uses methods like neuroimaging and studies of brain-damaged patients to tand how memory processes are represented in the brain. pproach (Difference due to Memory): A method in cognitive neuroscience to study memory encoding by comparing esponses to stimuli that are later remembered versus those forgotten. er et al., (1998) Study: This research used the Dm approach with event-related fMRI, contributing to the tanding of how deep encoding tasks impact memory. ain Regions in Memory Encoding: Includes the ventrolateral and dorsolateral prefrontal cortex, posterior parietal and medial temporal lobe. Each region plays a distinct role in memory encoding and retrieval. parietal Attention Network: This network is involved in managing attention, which is crucial for encoding and ng memories. Different parts of this network are associated with different types of attention (top-down vs. bottom- Temporal Lobe Functions: Beyond memory, the medial temporal lobe is involved in various functions such as construction, novelty detection, and consolidation. ng-Related Brain Activity: Research has shown that the timing and location of brain activity are crucial for tanding how memories are encoded. Elicited Activity: Most studies focus on brain activity immediately following an event, which is critical for tanding how memories are formed. mulus Activity in Memory: Indicates that brain activity before an event can influence how well that event is encoded emory. ng Systems in the Brain: There is evidence suggesting the existence of multiple encoding systems in the brain, ced by the type of task and material being encoded. PSYC0031 Cognitive Neuroscience Page 2 Key studies 1. Wagner et al. (1998) Method: This study used the Difference due to Memory (Dm) approach with event-related fMRI. Participants were shown a series of 480 words and asked to judge each word as abstract or concrete (deep encoding task). After 20 minutes, they underwent a recognition memory test with confidence judgments. Outcome: The study was pioneering in applying the Dm approach with fMRI, which allowed for the observation of brain activity related to successful memory encoding. Implications: This study opened up a new method of understanding how memory encoding works in the brain, particularly the impact of deep encoding tasks on memory retention. 2. Fernandez et al. (1999) and Galli et al. (2014) Method & Outcome: The exact methodology and outcomes of these studies are not detailed in the provided document. However, these studies likely explored aspects of memory encoding, considering the context of the lecture. Implications: These studies would contribute to the broader understanding of memory encoding and its neural correlates, particularly in the context of cognitive neuroscience. 3. Gruber & Otten (2010) Method: This study looked at pre-stimulus activity and its prediction of encoding success. The focus was on the activity before word onset in a high-reward condition. Outcome: The study found that pre-stimulus activity predicted encoding success but only in high-reward conditions, suggesting that this activity might reflect a voluntary strategic state to enhance encoding. Implications: This finding is significant as it suggests that the brain's state before encountering a stimulus can influence how effectively that stimulus is encoded into memory. It also indicates a connection between reward motivation and memory encoding. 4. Galli Wolpe & Otten (2011) Method: This study focused on how pre-stimulus activity predicted encoding success for negative pictures. Outcome: The main result was that pre-stimulus activity predicted encoding success, but this was particularly true for negative pictures and was more pronounced in women. Implications: This study highlights the role of emotional valence and gender in memory encoding. It suggests that emotional content, especially negative emotions, can influence how memories are encoded and that this effect may vary by gender. Notes Notes PSYC0031 Cognitive Neuroscience Page 3 Notes Notes PSYC0031 Cognitive Neuroscience Page 4 PSYC0031 Cognitive Neuroscience Page 5