Note
Studied by 21 peopleFinal Exam Notes!
Chapter13_Book
Memory and Learning Overview
Memory is crucial for learning and human individuality.
Henry Molaison's case (Patient H.M.) provides insights into memory's mechanisms and importance.
Key Concepts
Memory Definition
Ability to:
Learn and neurally encode information.
Consolidate information for long-term storage.
Retrieve/reactivate consolidated information later.
Types of Memory
Declarative Memory: Facts or information accessible to consciousness (e.g., memories we can declare).
Nondeclarative Memory: Skills and tasks learned through performing (e.g., riding a bike).
Also known as procedural memory.
Amnesia Types
Retrograde Amnesia: Difficulty retrieving memories formed before an event (e.g., surgery).
Anterograde Amnesia: Difficulty forming new memories after an event.
Henry Molaison's Case Study
Suffered severe anterograde amnesia after surgery to treat epilepsy.
Surgery removed most of the medial temporal lobes, including the hippocampus.
Could not form lasting new memories post-surgery, despite intact old memories.
Demonstrated a distinction between short-term and long-term memory.
Memory Formation Process
Encoding: Initial learning of information.
Consolidation: Transforming short-term memories into long-term ones; requires the hippocampus.
Retrieval: Accessing and using stored information from long-term memory.
Memory Stages
Sensory Buffer: Very brief storage of sensory information.
Short-Term Memory (STM): Duration of seconds to minutes, easily disrupted without rehearsal.
Long-Term Memory (LTM): Enduring memories lasting days to years, subject to potential distortion during recall and reconsolidation.
Brain Structures Involved in Memory
Hippocampus: Essential for forming long-term declarative memories.
Amygdala and Mammillary Bodies: Important for the emotional aspects of memories; damage can affect memory.
Cerebral Cortex: Stores long-term memories, including general knowledge and experiences.
Various brain regions contribute to specific types of memory, such as spatial learning and procedural memory.
Neuroplasticity and Memory
Neuroplasticity: Neural changes in response to experience that influence learning and memory.
Long-Term Potentiation (LTP): A stable increase in synaptic transmission efficiency following repetitive stimulation, believed to be a cellular mechanism for memory.
LTP relies on:
NMDA receptors: Work with AMPA receptors to facilitate memory formation.
Environmental Effects on Memory Development
Enriched environments can enhance brain structure and function, improving learning outcomes.
E.g., Increased synaptic connections and enhanced dendritic branching observed in animals from enriched settings.
Types of Nondeclarative Memory
Skill Learning: Procedural memory development, such as mirror tracing.
Priming: Improvement in processing stimuli due to previous exposure.
Associative Learning: Involves conditioning while including both classical conditioning (e.g., Pavlov's experiments) and instrumental conditioning (operant conditioning).
Emotional Influence on Memory
Emotionally charged events are remembered more vividly due to biochemical changes influenced by neurotransmitters like epinephrine acting on the amygdala.
Medications (like propranolol) show potential for altering the emotional impact of certain memories, especially in PTSD.
Conclusion
Memory, integral to learning and individuality, is complex, encompassing various forms, mechanisms, and neural networks. Henry Molaison’s case exemplifies the fragility of memory and its profound significance to identity and human experience.
Chapter13_PPT
LEARNING & MEMORY OVERVIEW
Core Concepts
Learning: The process of acquiring information.
Memory: The ability to store and retrieve information.
CASE STUDY: PATIENT H.M.
Background: Henry Gustav Molaison suffered from severe epilepsy due to a bicycle accident. At age 27, he underwent surgery to remove parts of his brain.
Surgery: Bilateral medial temporal lobectomy, removing medial portions of both temporal lobes, including the hippocampus, amygdala, and surrounding cortex.
SURGERY RESULTS
Immediate Effects:
General convulsions eliminated.
Reduced frequency of partial seizures.
Decreased use of anti-convulsant medication.
No change in perceptual or motor abilities; slight intelligence increase.
AMNESIA AND MEMORY IMPAIRMENT
Consequences of Surgery: Severe memory impairment with both retrograde and anterograde amnesia.
Retrograde Amnesia: Loss of memories formed before the injury. Mild retrograde amnesia noted; limited memory of events from 2 years prior to surgery.
Anterograde Amnesia: Inability to form new memories post-injury. Short-term memory remains intact; can hold new info momentarily if attended to (e.g., digit-span task).
MEMORY TYPES
Declarative Memory (Explicit): Memory of facts and autobiographical information. Classified into:
Episodic Memory: Personal experiences.
Semantic Memory: General knowledge and facts.
Non-declarative Memory (Implicit): Skills and conditioned responses, can operate without awareness.
Procedural Memory: Skill learning, doesn’t require the medial temporal lobe; relies on basal ganglia, cerebellum, and motor cortex.
Priming: Changes in perception influenced by previous exposure to similar stimuli, linked to reduced activation in specialized brain areas such as the occipitotemporal cortex.
Associative Learning: Learning relationships between events; includes classical and instrumental conditioning.
NON-DECLARATIVE MEMORY EXAMPLES
Classical Conditioning: Requires cerebellum, not hippocampus.
Involves unconditioned (US, UR) and conditioned stimuli (CS) with responses (CR).
Instrumental Conditioning: Learning actions yield certain consequences, not tied to specific brain regions.
MEMORY TESTING AND IMPLICATIONS
Various memory tests, such as the mirror drawing task and incomplete pictures task, show patient H.M.’s preserved implicit memory despite declarative memory deficits.
Important: Ensuring awareness of sensory modalities in memory tests is crucial. Some patients display global amnesia, while others do not.
SCIENTIFIC INSIGHTS FROM H.M.
Findings illustrate that memory functions are not uniformly distributed in the brain. The medial temporal lobe plays a vital role in memory consolidation, with distinct processes for short-term vs. long-term memory.
ANIMAL MODELS OF MEMORY
Studying animal models like monkeys and rats has shown that damage to the hippocampus and related areas disrupts recognition memory, informing our understanding of memory processing in humans.
COMPONENTS OF MEMORY
Memory Stages:
Sensory Buffers: Brief glimpses of memory.
Short-Term Memory (STM): Active attention span temporarily holding information (working memory).
Long-Term Memory (LTM): Durable storage of information post-attention.
MEMORY PROCESSES
Encoding: Inputting information into STM.
Consolidation: Transferring information from STM to LTM.
Retrieval: Accessing stored information back into working memory.
NEUROPLASTICITY
Changes in synapse structure and function underpin learning and memory. This includes mechanisms for enhancing or diminishing synaptic responses.
Neuroplasticity involves structural alterations like synapse formation, increased dendritic branches, and cellular changes due to experiences.
SYNAPTIC PLASTICITY & MEMORY
Long-Term Potentiation (LTP): A stable, long-lasting enhancement in synaptic transmission linked to memory formation, showing parallels with memory retention processes.
Role of Glutamate: Acts as a neurotransmitter crucial for LTP, highlighting importance in synaptic enhancements during memory formation.
MEMORY STORAGE STRATEGIES
Memories stored across various brain regions participate in the original experience, making them resilient to localized brain damage. Key Brain Areas:
Inferotemporal Cortex: Visual patterns.
Amygdala: Emotional significance.
Prefrontal Cortex: Tasks with sequential responses.
Cerebellum: Motor skills.
Striatum: Stimuli-response relationships.
This overview synthesizes key insights on learning and memory processes, particularly through the lens of H.M.'s case study and broader neuropsychological research on memory systems and mechanisms.
Chapter13_Audio pt.1
Definitions of Learning and Memory
Learning: The process of acquiring information that results in structural changes in the brain such as synapses and circuitry.
Memory: The ability to store and retrieve information.
Relationship between Learning and Memory
Learning and memory are interconnected; you assess learning by probing someone's memory for information.
Most aspects of existence, including languages, skills, and cultural practices, are learned behaviors.
Case Study of Henry Molaison (H.M.)
Background: Born in 1926; suffered from severe seizures caused by an accident leading to brain surgery in 1953.
Surgery: H.M. underwent a bilateral medial temporal lobectomy, removing parts of the medial temporal lobe (including the hippocampus and amygdala), which successfully reduced seizures but led to significant memory issues.
Post-surgery effects:
Seizures controlled: General convulsions eliminated, partial seizures decreased.
Memory deficits: Experienced both retrograde (loss of memories prior to surgery) and anterograde amnesia (inability to form new long-term memories).
Retrograde Amnesia: Mild; retained major memories from childhood but lost memories from the two years preceding the surgery.
Anterograde Amnesia: Severe; unable to form new memories after the surgery.
Short-term memory intact: Could repeat numbers immediately but failed to retain those numbers long-term after distraction.
Cognition: IQ increased slightly post-surgery, indicating no change in intelligence despite severe memory deficits.
Implications of H.M.’s Case
Memory Structure: Provided crucial insights into the function of different types of memory and the brain regions associated with them.
Types of Memory:
Declarative Memory (Explicit): Facts and knowledge that can be consciously recalled.
Semantic Memory: General knowledge without recollection of where or when learned.
Episodic Memory: Specific events and experiences, contextual information regarding "when" and "where".
Non-declarative Memory (Implicit): Skills and actions, like procedural tasks (e.g., riding a bike) which do not require conscious thought.
Findings by Brenda Milner
Studied H.M. and discovered longer-lasting effects of memory types.
Declarations: Found distinctions between short-term and long-term memories governed by different regions—hippocampus for consolidation and different areas for storage.
Consolidation: H.M. could form initial impressions but couldn’t retain due to missing hippocampal function.
Skill Learning: H.M. retained the ability to learn tasks through repetition even if he forgot performing them, showing the difference between procedural and declarative memory.
Memory Research Developments
Language Processing: Memory for facts (semantic) and personal experiences (episodic) are distinct, but also intertwined.
The ability for procedural memory remains intact despite declarative memory losses, allowing individuals to perform tasks without remembering having learned them.
Priming: Exposure to one stimulus influences the response to another stimulus, showcasing implicit memory capabilities.
Memory and Brain Regions
Cerebellum and Basal Ganglia: Critical in procedural (implicit) memory; unaffected in H.M.’s case post-surgery.
Hippocampus: Central to memory consolidation; removal leads to inability to transfer memories from short-term to long-term.
Key Notes on Different Types of Learning
Associative Learning:
Classical Conditioning: Learning through associations; e.g., Pavlov's dogs.
Operant Conditioning: Learning through reinforcement, e.g., training pets or classroom behavior.
Implementing Memory Research
Be mindful of sensory modalities used in tasks (visual, motor, verbal) alongside cognitive aspects for more effective memory assessments.
Distinction between learned responses should guide interaction with those experiencing memory deficits.
Chapter13_Audio pt.2
Chapter Overview
Focus on learning and memory processes.
Discussion on memory systems focused on short-term and long-term memory.
Importance of regions like the hippocampus and medial temporal lobe for memory consolidation.
Memory Storage and Types
Memory is not localized to one area but distributed throughout the cortex.
Two main types of memory:
Short-Term Memory (STM)
Lasts about 15-30 seconds unless rehearsed.
Working memory is a component of STM, allows manipulation of information.
Long-Term Memory (LTM)
Can last for years, no known limit for storage.
Different types:
Declarative (Explicit) Memory:
Can be verbally expressed. Further divided into:
Episodic Memory: Personal experiences.
Semantic Memory: General knowledge and facts.
Non-Declarative (Implicit) Memory: Skills and tasks that cannot be easily verbalized.
Case Studies
Case of H.M.:
Underwent medial temporal lobe surgery, affecting explicit memory but leaving implicit memory intact (e.g., skills).
Demonstrates separation of memory systems—highlighting hippocampus for consolidation.
Animal Models of Memory
Delayed Non-Matching to Sample Test:
Used with monkeys and rats to study object recognition memory.
Performance significantly lower in those with medial temporal lobe damage.
Different regions play unique roles:
Hippocampus: Important for spatial recognition.
Rhinal Cortex: Crucial for object recognition.
Neuroanatomy and Memory
Hippocampus: Critical for consolidation and recalling memories.
Amygdala: Involved in emotional aspects of memories.
Frontal Cortex: Plays a role in working memory, decision-making processes.
Memory Processes
Encoding: Input of sensory information into memory.
Consolidation: Process of transferring information from STM to LTM.
Retrieval: Bringing stored information back into working memory.
The process of Reconsolidation updates already stored long-term memories.
Memories can change upon retrieval, making them susceptible to errors.
Neuroplasticity
Brain's ability to adapt and change in response to experience.
Structural and functional changes in neurons (e.g., synapses) occur through learning.
Evidence from studies on rats indicates environment enrichments lead to better outcomes in learning and memory.
Long-Term Potentiation (LTP)
A mechanism for synaptic strengthening contributing to long-term memory.
Occurs through repeated activation of synapses leading to enhanced synaptic responsiveness.
Hebbian Plasticity: "Cells that fire together wire together"; repeated coactivation leads to stronger connections.
Key neurotransmitter involved: Glutamate, affecting NMDA and AMPA receptors, allowing calcium influx for memory enhancement.
Conclusion
Memory is a complex process involving multiple brain structures and systems.
Continuous learning from experience leads to neuroplastic changes, memory storage, and retrieval capabilities.
Questions/Tips for Study
Focus on distinguishing between short-term and long-term memory processes.
Understand the roles of specific brain regions in different types of memory.
Be prepared to explain concepts like reconsolidation and neuroplasticity with examples.
Clarify concepts related to synaptic plasticity and how they relate to learning.
Chapter14_Book
Attention and Perception
Introduction to Attention
Definition: Attention (or selective attention) refers to the process of focusing on specific stimuli, enhancing their processing.
Historical Insight: William James (1890) described attention as the mind's ability to concentrate on one of several possible objects or thoughts, involving a withdrawal from others.
Case Study: Parminder
Background: Parminder, whose family has a history of heart-related illnesses, suffered bilateral strokes that affected the parietal lobes.
Symptoms: Post-strokes, she could only perceive one object at a time (simultagnosia). For example, she could not simultaneously recognize her husband's face and glasses.
Perception Issue: This illustrates the limitations of attention in processing visual stimuli.
Types of Attention
Selective Attention: Choosing specific stimuli for detailed processing.
Vigilance: General level of alertness and readiness to respond.
Overt Attention: Attention aligns with sensory orientation (looking and attending to the same object).
Example: Watching a football game and analyzing plays.
Covert Attention: Focus can shift without changing where one's gaze is directed, like sneaking glances at peripheral stimuli.
Cocktail Party Effect: Ability to focus on one conversation amidst noise; demonstrates the filtering nature of attention.
Attention Processes
Shifts focus from one stimulus to another, acting as a filtering mechanism.
Consequences of Attention: Attention enhances perception but has limitations due to the nature of cognitive resources used.
Limitations of Attention
Attention is a limited resource, which can cause inattentional blindness.
Inattentional blindness: Failure to notice unexpected items when focused on another task.
Studies show that even experts can overlook obvious cues (e.g., a gorilla in a video).
Divided Attention: Difficulty in processing multiple stimuli, particularly when they require the same resources (e.g., looking at two different things).
Theories on Attention
Early Selection Model: Filters out unattended stimuli early in processing.
Late Selection Model: Unattended stimuli may get processed to some extent before being filtered out.
Perceptual Load: The complexity of a stimulus affects attentional resources; high complexity leads to early filtering.
Types of Attention Studies
Voluntary Attention (Endogenous): Consciously directed; studied through cuing tasks (e.g., Posner's task).
Reflexive Attention (Exogenous): Involuntary capture of attention through sudden changes in the stimulus.
Inhibition of Return: A phenomenon where attention does not return to a location that was previously cued, typically after a delay.
Visual Search
Feature Search: Quick identification based on a single attribute (e.g., finding a red dot amongst blue dots).
Conjunction Search: Slower and requires attention to multiple features (e.g., identifying a specific colored shape in a mixed array).
Event-Related Potentials (ERPs) in Attention
N1 and P1 effects: ERP components that indicate attentional processing; larger when stimuli are attended to compared to ignored ones.
Visual Attention: Enhanced P1 for attended stimuli in cuing tasks, illustrating the efficiency of attention in visual processing.
Cortical and Subcortical Mechanisms
Dorsal Frontoparietal Network: Governs voluntary attention; involves areas like the intraparietal sulcus.
Right Temporoparietal Junction: Involved in reflexive attention toward unexpected stimuli.
Disorders of Attention
Hemispatial Neglect: Condition where individuals ignore stimuli on one side, typically due to right hemisphere lesions.
Balint’s Syndrome: Characterized by simultagnosia and difficulty with visually guided movements due to bilateral parietal damage.
Attention Deficit Hyperactivity Disorder (ADHD): A disorder associated with impaired sustained attention, impulsivity, and variability in attention patterns, treated often with stimulants.
Consciousness and Decision Making
Consciousness is closely tied to attention and decision-making processes, often impacted by frontal lobe functions.
Free Will: The notion that our consciousness influences decision-making, despite evidence suggesting unconscious brain activity precedes conscious decisions.
Summary
Attention plays a critical role in perception and interaction with the world, affecting cognitive functions and neural activity. Mechanisms of attention not only help focus our cognitive resources but also shape our conscious experiences and decisions.
Chapter14_PPT
What is Attention?
Definition by William James (1890):
"Everyone knows what attention is…
Taking possession by the mind of one out of several possible objects or trains of thought.
Focalization, concentration, and withdrawal from other stimuli are essential to attention.
Attention allows for effective dealing with stimuli while filtering out others.
Selective Attention
Process of focusing on one or more stimuli for enhanced processing and analysis.
Examples:
A dog watching a leaf.
Listening to a lecture.
Vigilance is a global level of alertness, scanning the environment for relevant stimuli.
Covert vs. Overt Attention
Overt Attention:
Focus coincides with sensory orientation (attending to what is being looked at).
Covert Attention:
Focus can be directed independently of sensory orientation (e.g., attending to one thing while looking at another).
Cocktail Party Effect
Phenomenon of selective enhancement of attention to filter out distractors in noisy environments (e.g., parties or restaurants).
Attentional Bottleneck
Attention serves as a filter to direct cognitive resources to what is most important.
It raises the question of when this bottleneck occurs:
Early Selection Models:
Filter out unattended information right away, at the sensory input level.
Meaning not processed; filtering based on physical characteristics.
Late Selection Models:
All incoming stimuli processed for meaning before any selection for attention is made.
Testing the Limits of Our Attention
Important concepts:
Shadowing Experiments
Inattentional Blindness
Change Blindness
Divided Attention
Perceptual Load
Shadowing Experiments
Participants focus on one of two streams of stimuli (e.g., dichotic listening).
Possible outcome:
Individuals may not report hearing their own name.
Referenced study: Cherry, 1953.
Inattentional Blindness
Failure to perceive stimuli that are not actively attended to.
Example: 80% of radiologists missed a gorilla in CT scans (Drew et al., 2013).
Change Blindness
Failure to notice a change in a visual scene.
Example videos can depict this phenomenon (links available).
Divided Attention
Processing two or more stimuli simultaneously.
Limited attention capacity; acts as a spotlight to help focus our cognitive resources and direct behavior.
Perceptual Load
Refers to the processing demands of a task:
Easy Tasks:
Resources available to process task-irrelevant stimuli.
Difficult/Complex Tasks:
No extra resources available; irrelevant stimuli excluded immediately.
Categories of Attention
Sustained Attention:
Attending to a stimulus/location for a prolonged period (e.g., problem-solving).
Voluntary Attention:
Conscious, top-down process aligned with goals (endogenous).
Reflexive Attention:
Involuntary, bottom-up process mediated by lower nervous system levels (exogenous).
Attention Aids in Search Processes
Feature Search:
Search for a target based on a unique attribute.
Conjunction Search:
Search based on a combination of features.
Why are Conjunction Searches Harder?
Require more cognitive effort and time.
Binding Problem:
Question of how the brain integrates various features processed by different regions into a single object.
Targets of Attention
Selecting key stimuli from the environment to focus cognitive resources on.
Measuring Attention
Cortical neuron activity synchronization when attending to a task.
Methods include:
EEG (Electroencephalogram)
Event-Related Potentials (ERPs):
Averaged EEG recordings to measure brain responses to repeated stimuli.
Measuring ERPs
EEGs recorded during tasks show variability across trials.
By averaging results over many trials, random variations cancel out, revealing stable task-related components.
Negative voltages charted above zero line (N1, N2, etc.) and positive voltages below (P1, P2, etc.).
Patterns in Shifts of Attention
Auditory stimuli and their effects on ERPs:
Predictable effects observed through shadowing experiments.
Larger negative N1 for attended stimuli, indicating selective attention effects on neural processing.
P3 Effect:
Positive wave associated with memory, responses to surprises, and higher-order processing (meaning, language, identity of speaker).
Review Video Note
Introduction
Challenge presented: Count yellow stars and red X's simultaneously.
Example of divided attention: difficulty in tracking multiple stimuli at once.
Results of the Challenge
Participants may have counted: 15 yellow stars and 13 red X's (plus a smiley face).
Highlights the limitations of attention.
Understanding Attention as a Limited Resource
Concentration typically occurs on one stimulus at the exclusion of others.
Engaging in divided attention leads to task switching, not simultaneous processing.
Selecting between tasks employs selective attention.
Analogy: Selective attention as a flashlight beam focusing on specific stimuli while others are dimmed.
Types of Attention Cues
Exogenous Cues
External stimuli capturing attention without conscious effort.
Examples: Bright colors, loud noises (causing moments of diversion).
Pop-out Effect: Salient visuals stand out (e.g., a yellow circle among green circles).
Endogenous Cues
Internal learned cues that require intention and understanding.
Example: An arrow only makes sense if one understands its indication.
Cocktail Party Effect
Ability to focus on one voice within a noisy environment.
Example: Hearing one’s name among many conversations draws attention (endogenous cue due to knowledge of the significance of one's name).
Inattentional Blindness
Defined as missing stimuli in the visual field due to focus elsewhere.
Example: Missing the smiley face while counting other shapes.
Change Blindness
Failing to notice changes in the environment.
Example: Noticing if your mother’s hairstyle has changed or rearranged furniture in a room.
Important distinction from inattentional blindness:
Inattentional blindness: Missing something visible.
Change blindness: Missing differences between two states.
Research Example
A study where people giving directions failed to notice a change in the researcher due to a large bookcase moving between them.
Demonstrates our limited attention and tendency to focus on a primary task at the expense of noticing changes in the environment.
Chapter14_Audio pt.1
Attention Lecture Overview
Definition of Attention: Attention involves focusing on particular stimuli to process information effectively.
William James' definition highlights that attention is about focusing on one out of several possible objects or thought processes, necessitating withdrawal from others.
Types of Attention:
Selective Attention: Focusing on one or more stimuli for advanced processing, allowing for better information processing in challenging environments.
Vigilance: A general state of readiness to respond to important stimuli.
Attention Distinction: Overt vs. Covert Attention
Overt Attention: Directly looking at the object of focus (e.g., gazing at a dog).
Covert Attention: Looking at one thing while actually focusing on something else, often in peripheral vision.
Cocktail Party Effect
Describes how selective attention allows us to understand a friend's voice over background noise, demonstrating the ability to filter stimuli based on relevance.
Attentional Bottleneck
Concept: Attention acts as a filter, narrowing focus where only significant information gets processed.
Early vs. Late Selection Models
Early Selection Models: Suggest that filtering occurs before meanings are processed (e.g., filtering based on sensory input).
Late Selection Models: Propose that all incoming information is initially processed for meaning before any filtering occurs.
Measurement of Attention
Shadowing Experiments: Techniques to test selective attention, demonstrating the difficulty in processing simultaneous auditory stimuli. Participants often can only report details from one channel while ignoring the other.
Inattentional Blindness: Noting significant features (like an unexpected 'gorilla' in scans) when focused on another task; highlights that we do not perceive information we aren't actively attending to.
Change Blindness: The phenomenon where people fail to notice changes in a visual scene, demonstrating gaps in our visual perception.
Divided Attention: The challenge of processing two or more stimuli simultaneously, showing that we often switch back and forth rather than truly multitask.
Search Types in Attention
Feature Searches: Easier, where one unique attribute (e.g., color) helps identify a target among distractors.
Conjunction Searches: More complex, requiring attention to multiple features (e.g., color and shape), demonstrating cognitive load differences.
Binding Problem: Discusses how our brains combine features to create coherent perceptions of objects, emphasizing the complexity of attention processes when faced with multiple stimuli.
Visual Search Examples: Talks through examples, including finding Waldo, emphasizing cognitive effort differences in conjunction vs. feature searches through the binding problem.
Concluding Thoughts: Attention is a limited resource that can be easily overwhelmed, indicating the importance of understanding its limitations in various environments, including educational settings.
Chapter14_Audio pt.2
Chapter12_Book
Howard Dully's Case
Biographical Background:
Howard Dully was diagnosed with schizophrenia at the age of 12.
His biological mother passed away when he was 4, leading to his father's remarriage to Lucille.
Howard had a difficult relationship with his stepmother, which included rebellious behavior typical of adolescence (e.g., breaking curfew).
Psychiatric Intervention:
Dully was brought to six different psychiatrists, all concluding his behavior was normal.
Walter Freeman, the seventh psychiatrist, diagnosed him with schizophrenia and performed a lobotomy in 1960.
Lobotomy Procedure:
The procedure involved administering electro-shock therapy for sedation, followed by using an ice-pick-like tool to alter Howard's brain.
This procedure disconnects parts of the prefrontal cortex, which are linked to decision-making and emotional regulation.
The total cost of the lobotomy was approximately $200.
Post-Procedure Effects:
Family members described Howard's condition post-surgery as lethargic and zombie-like, leading to long-term institutionalization.
At age 50, Dully discovered his traumatic history and recounts his journey in his memoir "My Lobotomy".
Understanding Psychopathology
Prevalence of Mental Illness:
Schizophrenia affects about 1% of the population globally.
The American Psychiatric Association's DSM-5 is utilized to diagnose psychiatric disorders.
Major depressive disorders show variable prevalence globally, affecting millions at some point in their lives.
Impact of Mental Disorders:
Mental illnesses like schizophrenia impose significant emotional and economic burdens on affected individuals and society.
Up to 50% of individuals report psychiatric symptoms at some point.
Key Concepts in Schizophrenia
Symptoms of Schizophrenia:
Positive Symptoms: Hallucinations, delusions, and disordered thinking.
Negative Symptoms: Lack of emotional expression, social withdrawal, and impoverished thought processes.
Cognitive Impairment: Problems with memory, attention, and decision-making.
Genetic and Environmental Influences:
Genetic studies indicate a hereditary component, with higher rates of schizophrenia among relatives of affected individuals.
Environmental stressors, such as prenatal complications and urban living, increase the risk.
Impact of Stress:
City living is associated with a higher occurrence of schizophrenia compared to rural areas, emphasizing the role of environmental stress.
Biological Underpinnings of Schizophrenia
Brain Abnormalities:
Enlarged lateral ventricles are commonly observed in individuals with schizophrenia, indicating the loss of brain tissue.
Abnormalities in the frontal lobes contribute to dysfunctional cognitive processes associated with the disorder.
Dopamine Hypothesis:
Antipsychotic medications primarily target dopamine D2 receptors, suggesting a correlation between dopaminergic activity and schizophrenia.
Antipsychotic Medications:
Traditional antipsychotics block dopamine receptors effectively but can cause side effects like tardive dyskinesia.
Newer atypical antipsychotics target multiple neurotransmitters, including serotonin, and are generally favored for their efficacy with fewer movement-related side effects.
Mood Disorders: Depression and Bipolar Disorder
Depression:
Characterized by prolonged feelings of sadness, loss of interest, changes in sleep and appetite, and suicidal ideation.
Strong genetic components exist, alongside environmental influences.
Treatment primarily involves SSRIs and cognitive behavioral therapy; however, the efficacy of SSRIs has been questioned.
Bipolar Disorder:
Defined by alternating periods of depression and mania.
Treatment often includes lithium for stabilization, alongside therapy.
Anxiety Disorders
Types of Disorders:
Includes phobias, panic disorder, generalized anxiety disorder.
High genetic susceptibility noted, especially related to the amygdala's functioning.
Treatment Approaches:
Benzodiazepines serve as commonly prescribed anxiolytics, affecting GABA receptor systems to reduce anxiety.
SSRIs can also be effective; they boost serotonin availability.
Obsessive-Compulsive Disorder (OCD)
Symptoms:
Involves persistent obsessions (intrusive thoughts) and compulsions (repetitive actions).
Commonly treated with SSRIs which enhance serotonin at synapses, and cognitive behavioral therapy.
Mechanisms:
Dysfunction of serotonin systems significantly contributes to OCD symptoms.
Post-Traumatic Stress Disorder (PTSD)
Description:
Involves re-experiencing traumatic events, leading to intrusive memories and heightened anxiety.
Genetic predisposition significantly factors into susceptibility.
Neurobiological Findings:
Changes in the structure and function of the hippocampus are often noted.
Hormonal factors, including cortisol regulation, also play a role in the disorder’s persistence.
Treatment Options:
Cognitive behavioral therapy, SSRIs, and exposure therapy are common methods used to mitigate PTSD symptoms.