Neuropsychology Flashcards
What is neuropsychology?
Neuropsychologist
- Are clinicians with knowledge of neuropsychological symptoms and test methods to carry out the diagnosis and treatment of patients with brain disorders
- Study the relationship between (physical) brain functions and behavior (in specific behavior, emotions and cognitions).
- Are scientist-practitioners.
How can neuropsychological research be divided and what are they?
- Fundamental neuropsychological research: focuses on the understanding of underlying cognitive disorders/processes and related brain structures using experimental paradigms.
- Clinically oriented neuropsychological research: focuses on (improving) the assessment and treatment of brain disorders.
What are some of the working domains of a neuropsychologist?
Hospitals, mental health care (GGZ), rehabilitation centers, forensic institutions, residential or nursing homes, specialized institutions, etc.
Very varied work, both in children and adults, multidisciplinary (works together with a lot of other (para)medical disciplines.
What is a neuro-myth?
A misconception generated by a misunderstanding, a misreading, or a misquoting of facts scientifically established (by brain research) to make a case for the use of brain research in education or other contexts. It often generates from overgeneralization of empirical research, and are reinforced/propagated by, for example, Hollywood.
Subtraction method
- Franciscus (Frans) Cornelis Donders
- 1818-1889
- Reaction time paradigm: The use of reaction times to evaluate cognitive processes
- Pure insertions: A single cognitive process can be inserted into a task without affecting the duration of other processes
- Fallacies of pure insertion: Potential other mental processes involved in tasks
- Solution: Include multiple tasks/contrasts.
- This method is used in brain imaging research and neuropsychological tests (Stroop).
- Criticism on neuropsychological tests: Limited ecological validity (gap between test and everyday behavior).
- Solution: Add questionnaires and observations, virtual /augmented reality can help standardize environment.
What is the dissociation? And what is the goal of it?
Dissociation relates to a specific loss of a function. Its goal is to identify the neural substrate of a particular brain function and/or on the localization of function using case studies, neuroimaging and/or neuropsychological testing.
Single dissociation
Difference between tasks due to brain lesion which must be associated with the aspect of behavior studied. It assumes a serial organization of function in the brain.
Double dissociation
Demonstrates that two (more or less) independent cognitive processes rely on different brain regions or mechanisms. However, a single neural network model can also show patterns of double dissociation, meaning that a pattern of double dissociation in two patients does not necessarily indicate independent modules.
How do we know when there is a dissociation?
- Scores on one task should significantly fall above or below the average of the normative group,
- and the difference between the performances on task A and B differ significantly from each other.
How can neuroimaging techniques be divided?
- Structural imaging: The visualization and analysis of anatomical properties of the brain. (CT, MRI, DTI, VBM, MRS).
- Functional imaging: The identification of brain activity and brain functioning. (fMRI, PET, EEG, ERP, MEG).
What are spatial and temporal resolution?
Spatial resolution: Sharpness of the image.
Temporal resolution: Speed of recording.
CT
- Principle: Uses multiple X-rays, taken at different angles to produce cross-sectional images.
- Produces a general image of an area.
- Minimal radiation
- Less expensive than MRI.
- Around 5 min.
- Relatively high resolution
- Able to produce different “slices” of the brain in several angles.
- Able to identify abnormalities in the brain.
- Benefits Faster and can provide images of tissue, organs and skeletal structure.
- Risks: Harmful for unborn babies, a very small dose of radiation, a potential reaction to the use of dyes.
Magnetic resonance imaging (MRI)
- Principle: Uses powerful magnetic fields and radiofrequency pulses to produce detailed images.
- Produces more detailed images of soft tissue, ligaments, and organs.
- No radiation.
- More expensive than CT scans.
- 15 min to 2 hours
- High resolution
- Clearer images of soft tissue compared to CT: MRI is able to distinguish between grey and white matter.
- Able to identify abnormalities in the brain
- Benefits: Produces more detailed images.
- Risks: Possible reactions to metals due to magnets, loud noises from the machine can cause hearing issues, increase in body temperature during long MRIs, claustrophobia.
Functional MRI
- Register moments of activity of the magnetic protons in the body.
- Increase activity in a certain area in the brain is associated with increased blood supply in these brain areas.
- Measures ratio between oxygen-rich and oxygen-poor hemoglobin
Electroencephalography (EEG)
- High temporal resolution
- Measures the electrical activity generated in the brain cells.
Clinical neuropsychology is physics and stamp collecting. Explain what those two terms mean.
Physics: mechanistic explanation.
Stamp collecting: Establishing phenomena.
Clinical psychologies includes two types of stamps. Name and explain them.
Clear categories: Which country? Which color?
Fuzzy categories: e.g. animals versus people.
Antiguity
- 400 BCE - 300 CE
- Philosophy meets empiricism
- Aristotle, Hippocrates, Herophilus, Galen
Aristotle
- 384-322 BC
- Highly influential thinker
- Heart is the seat of intelligence
- Brain cools the body
Hippocrates
- 460-370 BCE
- Father of modern medicine
- Brain is for mental functions
- Pioneered lesion observations
Herophilus
- 335-280 BCE
- Pioneered observation over philosophizing.
- Described the nervous system through dissections
Claudius Galen
- 129-216 CE
- Pioneered dissection and comparative anatomy
- Mapped ventricular system and cranial nerves
- Distinguished sensory and motor nerves
How was neuropsychology like before the Renaissance?
- Gross anatomy was established
- Some idea that the brain is important for mental function
- No specific theory of brain-behavior relationships
Why was there so little progress over hundreds of years?
- Notion that the soul had no physical basis
- Experimentation on humans is forbidden
- Scientific method is not fully established
Renaissance
- 1500-1900
- The scientific method takes hold
- The soul gets localized
- Vesalius, René Descartes, Franz Joseph Gall
Vesalius
- 1515-1564
- Founder of human anatomy
- Created detailed descriptions and drawings of the anatomy of the brain
René Descartes
- 1596-1650
- Shaped mind-body dualism
- Viewed the body as a machine
- Influenced empirical physiology
Franz Josef Gall
- 1758-1828
- Shaped the idea of localization
- Developed phrenology
Neuropsychology before the 19th century
- More knowledge about the structure of the brain
- Relationship between brain and behavior still unclear
- No conceptual framework that ties both together
- Views were heavily influenced by religious and political ideas.
19th century
- 1800- WWI
- The dawn of brain mapping
- Language problems in France and Germany
- Jean-Martin Charcot, Paul Broca, Carl Wernicke, John Hughlings Jackson
Jean-Martin Charcot
- 1825-1893
- First professor of neurology
- First described and categorized many neurological disorders
- Developed systematic examination
- First associated specific lesions with clinical symptoms
Paul Broca
- 1824-1880
- Identified a critical area of language production
- Established methods of behavioral observation and post-mortem anatomy
John Hughlings Jackson
- 1835-1911
- Suggested a hierarchical organization of the brain
- Founded the first dedicated journal for neurology (brain)
- Distinguished between different types of epilepsy
Francis Galton
- 1822-1911
- Brought mathematical concepts to psychology
- Pioneered psychometric assessment
20th century
- 1900-1990
- Gun revolutionize neuropsychology
- Strict localization fades away
- Guns & rifles. Aleksandr Luria, Jerry Fodor, Brenda Milner
Guns & Rifles
- Treatment of headshot wounds in WWI and WWII advances neuropsychology
- Realization that the brain functions as an integrated whole (“holism”)
Aleksandr Luria
- 1902-1977
- Studied soldiers with brain injuries
- Pioneered systems view of brain functions
- Developed a comprehensive assessment battery
- Developed rehabilitation protocols for brain injury
Jerry Fodor
- 1935-2017
- Introduced the concept of modularity: brain processes that operate independently
- Turned away from holism and connectionism
Brenda Milner
- Born 1918
- Uncovered the brain basis of memory through her work with Henry Molaison (Patient H.M.)
- Established dissociations between different aspects of memory
What lessons did we learn from the history?
Diaschisis, Compensation, Individual differences
Diaschisis
- Greek for “shocked through”
- Brain injury or disease may have one or more widespread effects:
1. Differences in organizations may influence information processing streams
2. Connections may affect transfer between areas (axonal lesions)
3. Differences in synchronization may affect communication
Compensation
- Test performances does not necessarily reflect the disrupted processing of a damaged mechanism
- Task can be performed using different strategies
- Participants can learn to adapt, e.g., use different substrates to perform the same task
Individual differences
Variation in typical brain anatomy and physiology
Limitations
Ethical practices, socio-cultural context, interdisciplinary
Dark history
- Experimentation without consent
- Using experimental medical procedures
- Racial and class judgment
- Misuse of assessments
How can we do better in the future ethically?
- Informed consent and independent ethical review
- Monitored guidelines for introducing new treatments
- More inclusive research, including Global Majority
- Incorporating theories from other disciplines and cultures
