Lecture6_NeuroMethods_Brain_injury_2025
Page 1: Introduction
Title: Methods in Biopsychology & Brain Injury
Course: PS11220
Lecture: 6
Instructor: Dr. Alexander Taylor
Email: alt48@aber.ac.uk
Location: Room 0.15, Penbryn 5
Page 2: Overview of Methods
Methods to Study the Living Human Brain:
Structural/Static Imaging:
CT (Computed Tomography)
MRI (Magnetic Resonance Imaging)
DTI (Diffusion Tensor Imaging)
Functional/Dynamic Imaging:
PET (Positron Emission Tomography)
fMRI (functional MRI)
EEG (Electroencephalogram)
Stimulation Techniques:
TMS (Transcranial Magnetic Stimulation)
Neuropsychology:
Lesion studies
Advantages & Disadvantages
Each imaging and stimulation method varies in effectiveness, cost, and application.
Page 3: Resolutions in Imaging
Important Resolutions:
Temporal Resolution: The ability to track changes over time (e.g., milliseconds for EEG).
Spatial Resolution: The detail of images produced and size of areas examined (e.g., CT and MRI).
Example: ATHENS 2004 Olympic Games – Men's 100m Final
Illustrated comparison of temporal and spatial resolution in a real-world scenario.
Page 4: Imaging Techniques and Resolutions
Techniques:
MEG (Magnetoencephalography)
EEG + ERP (Event-Related Potentials)
fNIRS (Functional Near-Infrared Spectroscopy)
Injury and Lesion Types:
Classification by severity: Mild, moderate, severe TBI (Traumatic Brain Injury).
Page 5: Historical Perspective
Development and advancements in various imaging techniques began in the early 20th century.
Page 6: Historical Development of EEG
1929: Hans Berger introduced EEG through documented research on the brain's electrical activity.
Page 7: Event-Related Potentials (ERPs)
Need for multiple trials to analyze ERP components like P100, N100, P200, etc.
Page 8: ERP Measurement
Averaging and Stimulus Categories:
ERP correlates with attention and categorization in reaction to stimuli presented.
Page 9: ERPs and Cognition
Key Components:
N400: Related to semantic processing.
N170: Related to facial recognition.
Page 10: Application of EEG
Low-cost EEG systems have been developed to assist locked-in patients communicate.
Page 11: CT Scanning Technology
Prototype CT scanner created by Sir Godfrey Newbold Hounsfield.
Page 12: Computed Tomography (CT)
Process:
Involves using X-ray source and detector for imaging.
Allows for three-dimensional reconstruction of internal structures.
Page 13: CT Imaging Findings
Highest regional cerebral blood flow (rCBF) observed at age 2 in grey matter.
Page 14: MRI Fundamentals
Involves 3.0 Tesla scanner generating a magnetic field.
Magnetic signals are crucial for aligning targeted atoms in biological tissue.
Page 15: MRI Imaging
Advantages:
Notably safer as it has no radiation exposure and provides better spatial resolution compared to CT scans.
Page 16: DTI Imaging
Key Features:
Quantifies the diffusivity of water molecules within axons to map white matter tracts.
Page 17: Comparisons of Imaging Techniques
MRI vs CT Advantages:
MRI: No radiation, better resolution, clear distinction of brain tissues.
MRI vs CT Disadvantages:
Generally more expensive and restrictive concerning metal in the setting.
Page 18: Challenges of MRI
Rates and potential complications due to equipment limitations, including excessive costs.
Page 19: Functional Imaging Overview
Structural Imaging: Analysis of anatomy.
Functional Imaging: Studies biochemical functions and metabolic processes.
Page 20: Overview of PET Scanning
PET is the first functional imaging method and relies on radioactive tracers to visualize brain activity.
Page 21: Growth of fMRI Research
Rapid increase in the use of fMRI for studying brain connectivity since 1990.
Page 22: BOLD Response Analysis
Components of BOLD Response:
Initial dip, overshoot, and post-stimulus undershoot measures to determine neuronal activity.
Page 23: fMRI Measurements
Monitors BOLD signals in relation to stimulus presentations over time.
Page 24: Timing in fMRI Studies
Concepts:
Involves region of interest (ROI) analysis and timing of fMRI signals to assess conditions efficiently.
Page 25: TMS Overview
Mechanism of Action:
Uses pulsed magnetic fields to stimulate brain regions, altering neural activity patterns.
Page 26: Mechanisms of TMS
Describes how rapidly changing magnetic fields induce electrical fields in the underlying cortex.
Page 27: Virtual Lesion Approach
Explores the effect of brain stimulation to simulate lesions and assess cognitive functions.
Page 28: Media Reference
Mention of relevance to BBC FOUR and neurology.
Page 29: Neuropsychology - Lesions
Brain Injury Causes:
Stroke, hypoxia, tumors, degenerative disorders, and epilepsy are acknowledged causes of brain injury.
Page 30: Limitations of Lesion Studies
Challenges include individuality and variability in brain mappings and the complexity of brain functions.
Page 31: Vulnerability of Brain Areas
Certain areas of the brain are more susceptible to damage, necessitating careful study designs.
Page 32: Solutions to Misleading Lesion Overlays
Implement subtraction methods to refine data analysis related to lesion comparisons.
Page 33: Summary of Imaging Techniques
The trade-off between spatial and temporal resolution, costs, and other practical considerations in neuroimaging.
Page 34: Additional Materials for Part 1
Recommended readings and video resources for an in-depth understanding of neuroimaging techniques.
Page 35: Introduction to Part 2
Focuses on Brain Injury & Damage, outlining critical areas for study.
Page 36: Part 2 Overview
Covers types of traumatic brain injury (TBI), treatment, and assessment mechanisms.
Page 37: Traumatic Brain Injury Information
TBI Facts:
Significant health issue with 1.4 million yearly emergency department treatments in the US.
Page 38: Types of Head Injuries
Distinction between Closed (blunt) and Open (penetrating) head injuries with examples.
Page 39: Focal Injury Characteristics
Discusses mechanisms leading to neuronal damage and resultant axonal injury post-trauma.
Page 40: Primary vs Secondary Injury Mechanisms
Exploring injury types and associated hypoxic conditions that complicate TBI.
Page 41: Intracranial Volume-Pressure Curve
Illustrates progressive changes in intracranial pressure in varying pathological states.
Page 42: Glasgow Coma Scale (GCS)
Tool for initial head injury assessment based on eye opening, verbal response, and motor skills.
Page 43: TBI Classification
Classifies TBI severity levels based on GCS score ranges.
Page 44: Mild TBI Characteristics
Management Strategies:
History taking, neurological exams, and imaging for decision-making.
Page 45: Mini Mental State Exam (MMSE)
Scoring and Implications:
Cognitive assessments to evaluate degree of cognitive impairment and dementia risks.
Page 46: Moderate TBI Signs
Identification includes confusion and altered consciousness; management includes CT scans and monitoring.
Page 47: Severe TBI Indicators
Severe impairment of commands and prolonged unconsciousness requiring immediate assessment and intervention.
Page 48: TBI Treatment Approaches
Strategies include managing intracranial pressure, ensuring blood flow, and long-term cognitive assessments.
Page 49: Cerebral Blood Flow Autoregulation
Mechanism of cerebral blood vessels responding to maintain consistent blood flow under varying pressures.
Page 50: Cerebrovascular Incidents
Types:
Hemorrhagic and ischemic strokes detailed with various causes and consequences.
Page 51: Terminology in Cerebrovascular Events
Definitions of ischemia, thrombus, embolus, and their implications in brain injury.
Page 52: Stroke Mechanisms
Describes:
Formation of thrombi and how emboli can lead to significant vascular blockages.
Page 53: Stroke Treatment Options
Includes surgical interventions, anticoagulants, and rehabilitation as treatment pathways.
Page 54: Overview of Degenerative Disorders
Presents various cognitive and motor disorders such as Alzheimer's and Parkinson's diseases and their implications.
Page 55: Alzheimer's Disease Mechanisms
Involves amyloid plaques and neurofibrillary tangles contributing to cognitive decline.
Page 56: Brain Structure Changes in Alzheimer's Disease
Comparison of brain imaging highlighting degeneration versus healthy brain structures.
Page 57: Tumor Characteristics
Differentiation between benign and malignant brain tumors and basic treatment methods.
Page 58: Tumor Treatments
Options available include radiation, chemotherapy, and surgical removal strategies.
Page 59: Tumor Compression Effects
Illustrates the physical impacts of tumors on surrounding brain structures.
Page 60: Part 2 Summary
Summarizes critical aspects of TBI, treatment strategies, and other brain-related incidents.
Page 61: Additional Materials for Part 2
Suggested reading and video resources for further exploration of brain physiology and behavior.