代写Biological Psychology调试数据库编程

日期：2025-02-17 05:23

Biological Psychology

l Definition:

¡ Study of the biological basis of behavior. and cognition, also known as behavioral neuroscience, biopsychology, or psychobiology.

¡ Integrates principles of biology to understand physiological, genetic, and developmental mechanisms of behavior. and cognition in humans and animals.

l Behavior: Observable actions performed by humans or animals.

l Cognition: Mental processes, including thought, memory, perception, and decision-making.

l Key Insights:

¡ Brain Plasticity: The brain’s ability to change structurally and functionally to adapt to new experiences or recover from damage.

¡ Evolutionary Perspective: Expansion of the prefrontal cortex (PFC) in humans enhanced intellectual abilities and distinguishes humans from other species.

¡ Neuroscience and Mental Health:

n Mental disorders and neurological diseases are profoundly impactful.

n Neuroscience provides a better understanding of these conditions, potentially reducing stigma.

The Scientific Method in Biological Psychology

1. Observation: Identify phenomena based on empirical evidence.

2. Hypothesis Formation:

a. Use inductive reasoning to propose testable explanations.

b. Example: Behavioral changes might correlate with neural activity.

3. Experimentation:

a. Design experiments to evaluate hypotheses systematically.

b. Use control groups to isolate variables and test effects reliably.

4. Interpretation:

a. Deductive reasoning to analyze results.

b. Apply skepticism to ensure conclusions are robust and unbiased.

5. Falsifiability:

a. Introduced by Karl Popper (1934).

b. A hypothesis must be testable and disprovable to be considered scientific.

c. Non-falsifiable claims (e.g., phrenology) are not scientific.

Experimental Approaches in Neuroscience

l Main Question: How does the brain produce behavior. and cognition?

l Methodology:

¡ Measure biological processes (e.g., neuron activity) and behavioral responses simultaneously.

¡ Use advanced tools (e.g., Neuropixels probes) to observe single-neuron activity during cognitive tasks.

¡ Example Studies:

n Speech processing in the superior temporal gyrus (auditory cortex).

n Word planning in the prefrontal cortex during speech tasks.

l Control Groups:

¡ Essential for determining the effects of interventions.

¡ Help compare experimental conditions against baseline.

l Validity:

¡ Control Validity: Ensures reliability under controlled conditions.

¡ Ecological Validity: Reflects the natural, real-world context of behaviors.

Analysis of Experimental Data

l Statistical Testing:

¡ Classic null-hypothesis significance testing assesses whether observed differences are due to chance.

¡ Bayes Factor: Provides a likelihood estimate comparing two competing hypotheses.

l Importance of Robust Analysis:

¡ Reduces errors.

¡ Enhances reproducibility of findings.

Neuroscience Applications

l Technological Advances:

¡ Tools like Neuropixels enhance understanding of neural activity in specific brain regions.

l Social-Reward Learning in Mice:

¡ Study: Mice given psychedelic drugs exhibited increased preference for ‘social’ environments, demonstrating enhanced social-reward learning.

l Potential Benefits:

¡ Novel methods may help treat mental and neurological disorders.

¡ Brain interventions could improve overall human cognition and behavior.

Open Science and Modern Research

l Open Science Movement:

¡ Aims to make scientific research transparent, reproducible, and accessible.

¡ Encourages sharing raw data, methodologies, and analyses.

l Human Factors in Science:

¡ Although the scientific method is robust, human errors or biases can affect outcomes.

¡ Emphasizing open science minimizes these risks and fosters collaboration.

Detailed Exam Notes: Lecture 2 - Basic Ideas in Modern Neuroscience

Main Assumption of Neuroscience

l Thebrainproduces all mental phenomena and behavior. This foundational idea drives the field of neuroscience and stems from centuries of scientific discoveries.

Historical Development of Neuroscience

1. Ancient Beliefs:

a. Early civilizations (e.g., Egyptians, Greeks) believed theheartwas the source of intellect and mental life.

2. Galen’s Contribution:

a. Romans thought the soul resided in the chest because the voice originates there.

b. Galen demonstrated that cutting the laryngeal nerve silences animals, proving that intellect and control originate in thebrain, where the nerve is connected.

3. René Descartes (Reflex Concept):

a. Proposed thatreflexesexplain some behaviors as physical phenomena, laying the groundwork for understanding involuntary actions.

4. Luigi Galvani:

a. Discoveredanimal electricity, showing that electrical signals could make frog muscles twitch, linking electricity to nervous system function.

5. Santiago Ramón y Cajal:

a. With the advent of microscopy, Cajal showed that thenervous systemis made up of discrete cells (neurons), refuting earlier beliefs in a continuous network.

6. Sir Charles Scott Sherrington:

a. Expanded the reflex concept to explain that even complex movements can arise from interconnected reflex circuits.

7. Wilder Penfield:

a. Stimulated the brains of conscious epilepsy patients during surgery and elicited specificconscious experiences, proving certain brain regions correspond to distinct mental phenomena.

Behavioral Neuroscience

l Definition: The study of the biological basis of behavior.

l Importance:

¡ Relevance:

n Brain dysfunction (e.g., mental disorders, neurological diseases) is a major problem for humanity.

n Understanding the brain can improve treatment and outcomes.

¡ Mystery:

n The human brain is the most complex system known to exist, and we are far from fully understanding its mechanisms.

Current Directions and Innovations in Neuroscience

1. Focused Ultrasound Stimulation:

a. Emerging non-invasive technology for influencing brain function, with potential applications in therapy and neuroscience research.

2. Psychedelic Research:

a. Renewed interest in using mind-altering substances (e.g., psilocybin, LSD) to treat conditions such as depression, PTSD, and anxiety.

3. Neuromarketing:

a. The application of neuroscience to marketing strategies, such as understanding consumer preferences.

b. Targeted Dream Incubation: A cutting-edge technique designed to introduce advertisements into people's dreams.

4. Brain-Machine Interfaces (BMI):

a. Innovations like Elon Musk's Neuralink aim to create devices capable of direct communication with the brain, potentially revolutionizing how humans interact with technology.

Key Figures and Discoveries

Scientist	Contribution
Galen	Brain as the source of mental phenomena; disproved the heart as the control center.
Descartes	Proposed reflexes as physical explanations for some behaviors.
Galvani	Discovered the role of electricity in nerve and muscle function.
Cajal	Demonstrated that the nervous system is composed of individual cells (neurons).
Sherrington	Showed that even complex behaviors arise from reflexive processes.
Penfield	Elicited conscious experiences through direct brain stimulation.

Key Takeaways

1. Central Question:

a. How does the brain produce mental phenomena and behavior?

2. Relevance:

a. Neuroscience addresses critical human issues, including mental health, neurological diseases, and brain dysfunction.

3. Future Directions:

a. Advancements in technology and methods (e.g., BMIs, psychedelics) are paving the way for transformative discoveries.

4. Challenges:

a. The complexity of the brain makes it one of the greatest scientific challenges.

Detailed Exam Notes: Lecture 3 - Macroscopic and Microscopic Neuroanatomy

Planes in Anatomy

l Planesdivide the body to describe directions, useful in anatomical terminology:

¡ Superior/Inferior: Above/Below.

¡ Anterior/Posterior: Front/Back.

¡ Medial/Lateral: Close to/Far from the midline.

l Rostro-Caudal Axis:

¡ Equivalent to the cranio-caudal axis in most vertebrates.

¡ In humans, this axis curves due to upright posture.

Overview of the Nervous System

1. Central Nervous System (CNS):

a. Comprises thebrainandspinal cord.

b. Protected by:

i. Bones(skull and vertebrae).

ii. Meninges:

1. Layers: Dura mater, Arachnoid mater, Pia mater.

2. Reinforcement structures:Falx cerebri(between hemispheres) andTentorium cerebelli(between cerebrum and cerebellum).

2. Peripheral Nervous System (PNS):

a. Includescranial nervesandspinal nerves.

Gray and White Matter

l Gray Matter:

¡ Darker regions due to high density of neuronal cell bodies.

¡ Forms:

n Nucleiin the CNS.

n Gangliain the PNS.

l White Matter:

¡ Lighter regions due to myelinated axons.

¡ Forms:

n Tractsin the CNS.

n Nervesin the PNS.

¡ Function: Connects regions of gray matter.

Functional Divisions of the Nervous System

1. Somatic Nervous System:

a. Connects to muscles and sensory receptors.

b. Controls voluntary movements and processes sensory input.

2. Autonomic Nervous System (ANS):

a. Regulates involuntary processes.

b. Subdivisions:

i. Sympathetic(thoracolumbar): Fight-or-flight.

ii. Parasympathetic(craniosacral): Rest-and-digest.

iii. Enteric: Controls gastrointestinal functions.

Anatomy of the Brain

1. Key Components:

a. Cerebrum:

i. Largest part of the brain, divided into two hemispheres.

ii. Cortex: Surface layer with gyri (ridges) and sulci (grooves), increasing surface area.

b. Cerebellum:

i. Coordinates movement and balance.

c. Brainstem:

i. Includes medulla oblongata, pons, and midbrain.

d. Pituitary Gland (Hypophysis):

i. Visible at the brain’s base, controls hormonal functions.

e. Diencephalon:

i. Includes the thalamus and hypothalamus.

f. Midline Structures:

i. Visible in sagittal brain cuts, e.g., corpus callosum, ventricles.

2. Gray Matter Structures:

a. Basal Ganglia:

i. Dorsal Striatum: Caudate nucleus, Lentiform. nucleus (Putamen + Globus pallidus).

ii. Ventral Striatum: Nucleus accumbens, Olfactory tubercle.

iii. Subthalamic nucleus(diencephalon).

iv. Substantia nigraandventral tegmental area(midbrain).

b. Limbic System:

i. Emotional and memory functions.

ii. Includes the hippocampus, amygdala, cingulate gyrus, fornix, and stria terminalis.

3. White Matter Tracts:

a. Intra-hemispheric: Within one hemisphere.

b. Inter-hemispheric: Between hemispheres (e.g., corpus callosum).

c. Projection Tracts: Link cortex to lower CNS areas.

Brain Imaging Techniques

1. Computerized Tomography (CT):

a. Uses X-rays to measure tissue density.

b. Generates detailed images by combining slices.

2. Magnetic Resonance Imaging (MRI):

a. Uses strong magnetic fields to align and excite atomic nuclei, producing high-resolution images.

3. Diffusion Tensor Imaging (DTI):

a. Maps white matter tracts by tracking water diffusion along axons.

Cellular Organization of the Nervous System

1. Neurons:

a. Specialized for signal transmission.

b. Components:

i. Dendrites: Receive input.

ii. Axons: Transmit output.

iii. Synapses: Connection points between neurons.

c. Morphology indicates direction of information flow.

d. Approximately86 billion neuronsin the human brain with10^15 synapses.

2. Glial Cells:

a. Support neurons and participate in neural signaling.

b. Types:

i. Astrocytes: Connect neurons to blood capillaries.

ii. Microglia: Clean up cellular debris.

iii. Oligodendrocytes(CNS) andSchwann Cells(PNS): Form. myelin sheaths to insulate axons.

Brodmann Areas

l Korbinian Brodmann:

¡ Created a map of the cerebral cortex based on microstructural differences.

¡ Brodmann areas are widely used to reference specific brain regions.

Neurodegenerative Diseases

1. Alzheimer’s Disease (AD):

a. Most common neurodegenerative disease and cause of dementia.

b. Characterized by:

i. Neurofibrillary tangles.

ii. Amyloid plaques.

2. Parkinson’s Disease (PD):

a. Second most common neurodegenerative disorder.

b. Defined by:

i. Lewy bodies, particularly in the substantia nigra.

c. Symptoms:

i. Bradykinesia (slowness).

ii. Rigidity.

iii. Tremor.

iv. Postural instability.

3. Multiple Sclerosis (MS):

a. Ademyelinating diseasewhere myelin loss disrupts neural signal transmission.

b. Causes:

i. Oligodendrocyte dysfunction.

ii. Microglial activity.

Comprehensive Exam Notes: Lecture 4 - The Physiology of the Brain

Core Functions of the Brain

1. Electrical Signals:

a. Brain functions are primarily based on neurons generating and transmitting electrical signals.

2. Metabolism:

a. The brain relies on a high level of metabolic activity.

b. Requires glucose and oxygen, supplied by the circulatory system and regulated by cerebrospinal fluid (CSF).

Circulatory System of the Brain

1. Blood Supply:

a. Suppliesoxygenandglucosefor cellular energy production.

b. Arteriesdeliver oxygen-rich blood;veinsreturn oxygen-depleted blood.

2. Key Arteries:

a. Vertebral arteriesandinternal carotid arteries:

i. Converge at theCircle of Willis, a protective loop ensuring continuous blood supply.

ii. Branch into:

1. Anterior, middle, and posterior cerebral arteries(forebrain supply).

2. Basilar arterybranches (brainstem supply).

3. Blood-Brain Barrier (BBB):

a. Composed of specialized capillaries surrounded byastrocytesandpericytes.

b. Regulates the passage of substances, protecting the brain from harmful agents.

Ventricular System and Cerebrospinal Fluid (CSF)

1. Structure:

a. Lateral ventricles(in all brain lobes),third ventricle, andfourth ventricle.

b. Connected by thecerebral aqueductand pathways to thesubarachnoid space.

2. CSF Production and Dynamics:

a. Produced by thechoroid plexusesin the ventricles (~500 mL daily).

b. Total volume: ~140 mL, refreshed 3-4 times a day.

3. Functions of CSF:

a. Cushions the brain, removes waste, and maintains homeostasis.

b. Glymphatic System: Clears brain debris (e.g., proteins, toxins) via CSF flow.

i. Efficiency depends onarterial pulsation, highest duringdeep sleep.

ii. Declines with aging, contributing to neurodegenerative disease risk.

4. Aging Effects:

a. Reduced deep sleep and arterial stiffness decrease glymphatic efficiency.

Strokes and Brain Circulation Disorders

1. Definition:

a. A stroke occurs when blood supply to a brain region is insufficient.

2. Types:

a. Ischemic (blocked blood flow).

b. Hemorrhagic (ruptured blood vessels).

3. Symptoms:

a. Depend on the affected brain region (e.g., motor deficits, speech difficulties).

Functional Imaging of the Brain

1. Positron Emission Tomography (PET):

a. Uses radioactive tracers to measure blood flow and metabolic activity.

b. Provides regional activity mapping.

2. Functional MRI (fMRI):

a. Tracks blood oxygenation differences (oxygenated vs. deoxygenated hemoglobin).

b. Reflects changes in neural activity over time.

Electrical Activity in the Brain

1. Overview:

a. Neural activity is based on ion movement across membranes, generating electrical signals.

b. Early research using squid neurons revealed the molecular basis of these signals.

2. Membrane Potential:

a. Resting potential (~ -70mV) is set by:

i. Potassium channels.

ii. Sodium-Potassium pumps.

iii. Negatively charged intracellular proteins.

b. Hyperpolarization: Increased potential difference (more negative inside).

c. Depolarization: Decreased potential difference (less negative inside).

3. Action Potential:

a. Triggered when a threshold potential is reached.

b. Propagated along neurons, enabling signal transmission.

c. Key mechanism for communication in the nervous system.

4. Electroencephalography (EEG):

a. Detects summated brain electrical activity via scalp electrodes.

b. Applications:

i. Sleep studies: Analyze sleep patterns.

ii. Event-Related Potentials (ERPs): Study cognitive responses to stimuli.

The Glymphatic System

1. Discovery:

a. Functions like the lymphatic system but is unique to the brain.

b. Glial cells facilitate CSF flow through brain tissue.

2. Role in Neurodegeneration:

a. Inefficient glymphatic clearance is linked to:

i. Alzheimer's disease (accumulation of amyloid-beta).

ii. Other neurodegenerative diseases.

3. Sleep Dependency:

a. Glymphatic flow peaks duringdeep sleep.

b. Aging disrupts deep sleep, reducing glymphatic efficiency.

Summary of Key Concepts

l Metabolic and electrical processesare central to brain function.

l Thecirculatory systemandCSF dynamicsmaintain brain homeostasis and waste clearance.

l Functional imaging and EEG provide insights into brain activity.

l Understanding the glymphatic system highlights the link between sleep, aging, and neurodegeneration.

Comprehensive Exam Notes: Lecture 5 - The Cellular Physiology of the Neuron

Overview of the Nervous System

l Thenervous systemrelies onneuronsto generate, conduct, and transmit electrical signals, which result in behavioral and cognitive phenomena.

l Neuronsare the fundamental units responsible for the brain's communication, whileglial cellsprovide support, nourishment, and protection to neurons.

Cell Structure and Function

1. Basic Components of a Cell:

a. Cell Membrane:

i. Separates the intracellular environment from the external environment.

ii. Vital for maintaining homeostasis by regulating what enters and exits the cell.

iii. Controls ion concentrations and pH within the cell, ensuring optimal conditions for protein function.

b. Cytoplasm:

i. The liquid inside the cell that contains the organelles and proteins essential for cell life.

ii. Organelles:

1. Endoplasmic Reticulum (ER): Synthesizes proteins and lipids, critical for cellular function and structure.

2. Mitochondria: The powerhouse of the cell. ProducesATP(energy) viacellular respiration(glycolysis, citric acid cycle, and oxidative phosphorylation), requiringoxygenandglucose, producingcarbon dioxideandwateras byproducts.

c. Nucleus:

i. Contains theDNA, which holds the genetic instructions for protein synthesis.

ii. The DNA is transcribed intomRNA, which is translated into proteins that perform. various cellular functions.

Electrical Properties of Neurons

1. Resting Membrane Potential:

a. The electrical potential difference across the neuronal membrane at rest (~ -70mV).

b. This potential is primarily determined by thesodium-potassium pump(Na+/K+ ATPase), which actively transportsNa+ions out of the cell andK+ions into the cell.

c. The differential distribution of ions across the membrane creates a negative charge inside the cell relative to the outside.

d. The cell membrane is selectively permeable to certain ions, especiallyK+(which leaks out of the cell), contributing to the resting potential.

2. Changes in Membrane Potential:

a. Hyperpolarization: Occurs when the inside of the cell becomes more negative than the resting potential (more negative than ~-70mV). This is usually caused by the influx ofCl⁻ions or efflux ofK⁺ions.

b. Depolarization: Occurs when the membrane potential becomes less negative or more positive (approaching 0 mV). This is due to the influx ofNa⁺ions.

Action Potential

1. Generation of Action Potential:

a. If the depolarization reaches a threshold (around -55mV), anaction potentialis initiated. The action potential is a rapid, all-or-nothing electrical event that propagates along the axon.

b. Voltage-Gated Ion Channels:

i. Sodium Channels: Open in response to depolarization, allowingNa⁺to rush into the cell, further depolarizing the membrane.

ii. Potassium Channels: Open later to allowK⁺to leave the cell, repolarizing the membrane.

c. Phases of Action Potential:

i. Resting State: All ion channels are closed.

ii. Depolarization: Sodium channels open, andNa⁺rushes in.

iii. Repolarization: Potassium channels open, andK⁺flows out.

iv. Hyperpolarization: Potassium channels remain open briefly, causing the inside of the cell to become more negative than the resting potential.

v. Refractory Period: After an action potential, the neuron briefly cannot fire another action potential (absolute refractory period), followed by a relative refractory period.

2. Propagation of Action Potential:

a. Action potentials propagate down theaxonwithout decrement, allowing the signal to travel long distances.

b. Inmyelinated axons, action potentials jump from one node of Ranvier to the next (saltatory conduction), which significantly increases conduction speed.

c. Unmyelinated axonsconduct signals more slowly as the action potential must propagate continuously along the axon.

Neural Transmission

1. Excitatory and Inhibitory Signals:

a. Excitatory Transmission:

i. Increases the likelihood that the postsynaptic neuron will reach the threshold for firing an action potential.

ii. Typically mediated byglutamate(the major excitatory neurotransmitter).

iii. Depolarizes the postsynaptic cell by allowingNa+influx.

b. Inhibitory Transmission:

i. Reduces the likelihood of an action potential firing by hyperpolarizing the postsynaptic cell.

ii. Typically mediated byGABA(the major inhibitory neurotransmitter).

iii. Increases the influx ofCl⁻or efflux ofK⁺, making the inside of the cell more negative.

2. Summation of Signals:

a. Spatial Summation: Multiple signals arriving at different locations on the neuron are summed together.

b. Temporal Summation: Multiple signals arriving at the same location in rapid succession are summed together.

Synaptic Transmission

1. Steps in Synaptic Transmission:

a. Action potentialreaches thepresynaptic terminal.

b. This triggers the opening ofvoltage-gated calcium channels, allowingCa²⁺to enter the presynaptic neuron.

c. The influx ofCa²⁺triggers the release of neurotransmitters from synaptic vesicles into the synaptic cleft byexocytosis.

d. Neurotransmitters then bind to receptors on thepostsynaptic membrane.

2. Neurotransmitter Receptors:

a. Ionotropic Receptors: These receptors areion channelsthemselves. When bound by neurotransmitters, they open and allow ions to flow into or out of the cell, causing rapid changes in membrane potential.

b. Metabotropic Receptors: These receptors activateG-proteinsthat indirectly influence ion channels via second messenger systems (e.g., cAMP), leading to slower but prolonged effects.

Cellular Protein Functions and Synthesis

1. Proteins in the Neuron:

a. Proteins are essential for nearly every function within the cell, including enzyme activity, signal transduction, structural support, and neurotransmitter synthesis.

2. Protein Synthesis:

a. DNAcontains the instructions for making proteins.

b. mRNAis transcribed from DNA and exported from the nucleus.

c. Ribosomesin the cytoplasm translate the mRNA into proteins by reading thecodonsand adding the correspondingamino acids.

d. tRNAmolecules bring amino acids to the ribosome, where they are added to the growing protein chain.

3. Axonal Transport:

a. Axonal transportmoves proteins and other materials from thecell bodyto theaxon terminals.

b. Microtubulesandmotor proteins(kinesin and dynein) facilitate the movement of materials along the axon.

Gene Expression

1. Central Dogma of Molecular Biology:

a. DNA→mRNA→Protein.

b. The sequence of nucleotide bases in theDNAdictates the amino acid sequence of proteins.

2. Gene Regulation:

a. Different cells express different proteins based ongene expression, which is tightly regulated.

b. Gene expression can be assessed by measuring the presence ofmRNAor the proteins themselves.

Neuroplasticity and Synaptic Changes

1. Dendritic Arborization:

a. Neurons can change their structure by growing new dendritic branches (arborization) or retracting old ones. This is a key component ofneuroplasticity, which allows for learning and memory formation.

2. Axonal Growth:

a. Axonal growth and guidance are influenced bychemoattractants(which attract axons) andchemorepellents(which repel axons).