Chapter 5 part 3

• Three approaches to neuropsychological testing:

  1. Single-test approach

  2. Standardized-test battery approach

  3. Modern customized-test-battery approach
• The single-test approach aimed to discriminate between patients with psychological problems from structural brain damage and those with problems from functional changes to the brain, but it was unsuccessful due to the complexity of symptoms
• The standardized-test battery approach involved using standardized sets of tests, like the Halstead-Reitan Neuropsychological Test Battery, to diagnose brain damage based on aggregate scores
• The customized-test-battery approach aims to characterize the nature of psychological deficits in each brain-damaged patient, using tests specifically designed to measure aspects of psychological function highlighted by modern theories and data
• Tests in the customized-test-battery approach differ from earlier approaches as they are designed to measure specific psychological functions, require the neuropsychologist to assess the patient's cognitive strategy, and demand more skill and knowledge to select the right tests
• Common tests in a neuropsychological test battery:

  • Wechsler Adult Intelligence Scale (WAIS) for intelligence
  • Digit span subtest for short-term memory
  • Token test for language-related deficits
  • Test of language lateralization to determine language dominance
• Tests of language lateralization:

  • Sodium amytal test: involves injecting anesthetic into carotid artery to anesthetize one hemisphere at a time
  • Dichotic listening test: sequences of spoken digits presented to each ear to determine language dominance
• Specific tests used by neuropsychologists to investigate general problems revealed by a common neuropsychological test battery:

  • Repetition priming tests for memory assessment
  • Complex series of tests for language-related deficits, focusing on phonology, syntax, and semantics
• Speech problems can be categorized into three fundamentally different problems:

  • Problems of phonology (the rules governing the sounds of the language)
  • Problems of syntax (the grammar of the language)
  • Problems of semantics (the meaning of the language)
• Testing of all neuropsychological patients with speech problems should include tests of phonology, syntax, and semantics capacities
• Reading aloud can be disrupted in different ways by brain damage, and follow-up tests must be employed
• Some dyslexic patients remember the rules of pronunciation but have difficulties pronouncing words that do not follow these rules
• Cognitive neuroscience focuses on understanding cognition and assumes that each complex cognitive process results from the combined activity of simple cognitive processes
• The default mode in the brain is active during internally focused tasks like daydreaming and thinking during wakeful rest
• The main goal of cognitive neuroscience is to identify the parts of the brain that mediate various constituent cognitive processes
• Mean difference images are obtained by averaging the difference images obtained from repetitions of the same tests to increase the signal-to-noise ratio
• The default mode network comprises four cortical areas: medial parietal cortex, lateral parietal cortex, medial prefrontal cortex, and lateral temporal cortex
• Functional connectivity in cognitive neuroscience refers to how network activity across multiple brain regions is related to a particular cognitive task
• Extrinsic functional connectivity studies changes in FC with the presentation of a stimulus or during the performance of a task, while intrinsic FC is present during the resting state-fMRI
• Resting state-fMRI (R-fMRI) is the pattern of activity during the default mode
• Three behavioral paradigms used to study species-common behaviors are the open-field test, tests of aggressive and defensive behavior, and tests of sexual behavior
• In the open-field test, low activity scores and high bolus counts are indicators of fearfulness
• The study of the functional connectome involves characterizing the functional connectivity associated with each behavior and cognitive process
• Behavioral paradigms used to study species-common behaviors include grooming, swimming, eating, drinking, copulating, fighting, and nest building
• Fearful rats are highly thigmotaxic, rarely venturing away from the walls of the test chamber and engaging in activities like rearing and grooming
• Rats are often fearful when first placed in a strange open field, but this fearfulness usually declines with repeated exposure to the same open field
• In the colony-intruder paradigm, the dominant male rat displays aggressive behaviors, while the intruder exhibits defensive behaviors
• Common measures of male rat sexual behavior include the number of mounts required to achieve intromission, the number of intromissions needed for ejaculation, and the interval between ejaculation and the reinitiation of mounting
• The elevated plus maze, a test of defensiveness, measures the proportion of time rats spend in protected closed arms rather than on exposed arms to assess anxiety levels
• The Pavlovian conditioning paradigm pairs a conditional stimulus with an unconditional stimulus to elicit a conditional response, while the operant conditioning paradigm increases or decreases the rate of a voluntary response through reinforcement or punishment
• The self-stimulation paradigm in biopsychology involves animals pressing a lever to deliver electrical stimulation to specific sites in their own brains, targeting pleasure centers
• Conditioned taste aversion is the avoidance response that develops to tastes of food followed by illness, challenging traditional principles of learning like gradual conditioning and the importance of temporal contiguity
• The radial arm maze, designed to mimic natural navigation challenges, consists of multiple arms radiating from a central area with a food cup at the end of each arm
• The Morris water maze is a seminatural learning paradigm where rats swim in a circular pool of water to find an invisible escape platform, useful for assessing navigational skills of brain-lesioned or drugged animals
• Conditioned defensive burying involves rats learning that a test object is a threat after receiving an aversive stimulus, responding by flinging bedding material at the object with their head and forepaws
• Multiple research methods are crucial in biopsychological research to answer questions effectively, as important issues are rarely resolved by a single method alone