Neuropsychology Week One Quiz

Research in Neuropsychology

• Galen proposed the Ventricular Localization Hypothesis, suggesting mental and spiritual processes reside in the brain's ventricles.
• Early attempts to localize mental functions led to later inaccuracies known as The Cell Doctrine.

Earliest Discoveries

• Trephination in the Stone Age aimed to relieve pressure on the brain by drilling holes in the skull, thought to be a magical healing practice for conditions like epilepsy and schizophrenia.
• Andreas Vesalius, the founder of human anatomy, moved away from the ventricular theory, positing that overall brain structure mediates mental processes.
• René Descartes introduced Mind-Body Dualism, proposing a split between mental processes and physical abilities, with the pineal gland acting as a control center.

Ancient Greek Perspectives

• Hippocrates argued that the brain is the source of all behavior, controlling senses and movement, and that emotions arise in the brain rather than being divinely controlled.
• Plato's Tripartite Soul Concept divided the soul into reason, spirit, and appetite, attributing reason to the brain.
• Aristotle's Cardiac Hypothesis stated that the heart is the seat of thought and emotion.

Localization Theory

• Franz Gall's localization theory suggested the brain is composed of independent organs, each responsible for specific traits, and introduced phrenology for personality assessment based on skull shape and size.

Era of Cortical Localization

• Paul Broca localized expressive language to the left frontal lobe, while Carl Wernicke localized receptive language understanding to the left temporal lobe.

Integrated Theories

• Hughlings Jackson proposed a functional model where higher mental functions are composed of simpler functions within a hierarchical brain structure, with damage to higher levels resulting in loss of complex functions.
• Alexander Luria developed a functional model with three units in the Central Nervous System (CNS) that regulate arousal, integrate sensory information, and plan and execute behavior.

Critique of Localization Theory

• Sigmund Freud emphasized that cognitive functions involve complex networks across the brain, necessitating an understanding of connectivity and interactions for comprehending behavior and cognition.

Relatively Modern Neuropsychology

• Advances in technology have significantly improved neuropsychological research and understanding of brain functioning.### Neuroimaging and Cognitive Neuroscience
• Expansion in research areas, notably cognitive neuroscience, allows for deeper understanding of brain functions.

Localization vs Equipotentiality

• Equipotentiality Theory: Proposed by Pierre Flourens, asserting that brain regions can perform many functions and can compensate for damages.
• Key Contributors:
  • Henry Hecaen: Explored functional properties of the right hemisphere (RH).
  • Arthur Benton: Developed methods for assessing RH capabilities.
  • Karl Lashley: Advocated the principle of mass action; behavior impairment correlates with the amount of tissue removed.
  • Norman Geschwind: Linked behavioral disturbances to disconnections in brain networks.
  • Muriel Lezak: Developed assessment methodologies in neuropsychology.

Research Methods: Structural Imaging

• Microscopic Brain Structure Analysis is essential for understanding neuronal organization.
• Key Techniques:
  • Golgi Stain: Visualizes entire neurons to study structural details and networks.
  • Nissl Stain: Highlights neuronal cell bodies for examining density and arrangement.
• CT Scans:
  • Provides cross-sectional images using X-rays.
  • Useful for detecting lesions and tumors; quick but limited resolution.
• MRI:
  • Offers detailed images by aligning hydrogen atoms; safer for repeated exposure.
  • Commonly used for detecting lesions with high sensitivity but is time-consuming and expensive.

Functional Neuroimaging

• fMRI (Functional MRI):
  • Measures brain activity through blood flow changes; useful for brain mapping and assessing metabolic activity.
  • Non-invasive with high spatial resolution but slower temporal resolution.
• PET (Positron Emission Tomography):
  • Visualizes metabolic processes using radioactive tracers.
  • Essential for diagnosing neurological disorders, although it involves radiation.
• SPECT (Single Photon Emission Computed Tomography):
  • Similar to PET but focuses on blood flow; involves radioactive tracers.

Electrophysiological Procedures

• EEG (Electroencephalography):
  • Records electrical activity of the brain, with a focus on brain wave patterns.
  • Non-invasive, useful for monitoring conditions like epilepsy, but has lower spatial resolution.
• Evoked Potentials (EPs):
  • Assesses brain responses to stimuli; applicable in diagnosing neurological issues like multiple sclerosis.

Cerebrospinal Fluid Studies

• Cerebrospinal Fluid (CSF):
  • Involves analysis of fluid surrounding the brain and spinal cord.
  • Lumbar puncture (spinal tap) used for sampling; important for diagnosing neurological conditions.