Psych 3513 Lecture IX — Chapter 3 • Methods of Cognitive Neuroscience, II — Dr. Siefke — 9 PDF

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Dr. Brian Siefke, continuing discussion on methods employed in cognitive neuroscience....

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Psych 3513 Lecture IX — Chapter 3 • Methods of Cognitive Neuroscience, II — Dr. Siefke — 9.16.2020 Reminder: Midterm 1 opens on Carmen the Friday of next week, 9/25 ● Must use Respondus Lockdown Browser ● Time length granted: 55 minutes ● Exam 1 Study Guide available on Carmen (List of Topics, Chapters 1, 2, 3, 5) Available on Carmen: Assignment 2: Research Article Summary ● Choose one of 5 given Journal Articles for your research article; ● Word length must be on an interval of [1,000, 1,200] (Remember measurable factors: §MC DRAPE; Measuring the Cognitive DRAPE) Continuing on Examples of Experimental Studies ● Letter Matching Test / Word Categorization Test (Mike Posner) ● Memory Comparison Task (Saul Sternberg) ● Word Superiority Effect ● Stroop Task ●

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Inferences of Mental Representation and Processing are critical to such studies. Ask 3 questions about any experiment: ○ (1) Claim being probed/tested ○ (2) Manipulation in experimental design ○ (3) Measurement(s) taken; assessing dependent/response variable(s)

Letter Category Matching Task ● 2 Letters presented ● Are they from the same category (both vowels, both consonants) or a different category? ○ Tap L hand for Same: or R hand for different ● Categorization Experiment: Differential Response Times by Task Form/Elements ○ Identical (AA), Phonetic Identity (Aa), Same Category (Both Vowels AU, or Both Consonants (SC), ◆ All require the same response ○ Different Categories (AS) ○ Chronometrics: Measuring of Response Time (RT α Mental Processing) ○ Tasks composed of set of mental operation, with each taking time. ◆ Steps: Encode. Compare, Decide, Respond (§ EnCoDeR) ◆ Encode: physical identity -> phonetic identity -> category (consonant or vowel) ○ Because there are less vowels than consonants, there is (Claim) more complex mental representation of consonants than vowels Sternberg, S (1966) High-speed scanning in human memory. Science, 153, 652-654 ● Subject is presented 1, 2, or 4 letters for memorization ● Then presented a probe letter after a delay (manipulation) and asked whether it was in the just-studied set ○ Task is hypothesized to require four operations (§ EnCoDeR) ● Can infer from reaction times (Claim) that the comparison process occurs in serial over entire set, not in parallel ○ Humans evince a cognitive limitation: of examining a

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Notably in a direct linear relationship between number of items in set and response time derived from experimental data. Concept drawn from computer science (recall the interdisciplinary triad, Ch. 1) ● Parallel Processing: Examining all letters at once (§PARse ALL ELements) ● Serial Processing: Examining each letter in order; (§ Study Each Ring In A Line) Word-Superiority Effect ● Does the stimulus contain an A or an E? Condition

Stimulus

Accuracy

Word

RACK

90%

Nonsense String (Manipul. 1)

KARC

80%

Xs (Manipul. 2)

XAXX

80%

Humans have a superior mental representation of words than non-words (Claim) ● Stronger accuracy (1 Measure) and recognition of elements within a word than within a non-word ○ Evidenced in Accuracy and in Reaction Time (Measurements) ● Mental representation of language is more refined than for nonintelligible character terms Stroop Task ● Say the color of the ink each word is printed in. ○ Task: State color of the ink ○ Largely effective in primary languages of subjects ○ Reaction Time and Errors jointly examined (Measurements)

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Stimuli activate 2 representations: ○ Physical color of text (task-relevant) ○ Color concept / semantic meaning (irrelevant to task) Task performance is worse when mismatched between text and tint (manipulation) -> interference ○ Conceptual representation automatically activated (Claim)

What can behavioral studies present to us? ● How much time is needed to perform different tasks? (Differential Duration for Task Performance) ● Is there interference? (What is the representation?) (Mental Representation Interference; MRI) ● What is one’s memory capacity under different conditions? (Differential Epistemic Capacity by Circumstances) ● How many separate subjects/things can people pay attention to? (Cardinal Attention Capacity) ○ Jointly reflect information about mental (potentially neural) representations (reflect on interdisciplinary empirical studies map from preceding lecture) Continued Outline Chapter 3: Methods of Cognitive Neuroscience Outline: ● Cognitive Psychology and Behavioral Methods ● Studying the Damaged Brain ● Methods to Perturb Neural Function ● Structural Analysis of Brain ● Methods for Study of Neural Function ● Neuroimaging: Structure and Function ● Computational Modeling

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Converging Methods

Consider what kinds of damage can emerge: ● Lesion: Any structural damage to white or gray matter ○ Can result from tumors (or contusions) ● Tumor (neoplasm): A mass of tissue which grows abnormally and has no physiological function. ○ Not always cancerous (that particularly regards mutations in oncogenes and cell cycle controls) ○ Not helping with action potentials, myelination, etc. Wastage of tissue area ○ May be benign (not significant in effect) or malignant (profoundly prejudicial)/ metastasizing (spreading) Know the following Tumors (Distinguished and differentiated by region of origin) ● Glioma (abnormal reproduction of glial cells ● Meningiomas (originate in the meninges, the protective membrane around the brain) ○ 2 Layers of dura mater, two layers of arachnoid mater, and 1 layer of pia mater ● Meastatic ([sic] as found in textbook; not metastatic(?)): originate in separate tissue or organ system and travels into brain. Vascular Disorders: Angiography ● Blood circulation gauged in the brain ○ Injecting dye into the brain ○ Through X-Ray, the structure and distribution will be projected; reflected ◆ Can help to diagnose vascular disorders ● To evaluate circulatory system and diagnose disruptions

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Dye is injected into vertebral (20%) or carotid (80%) arteries and diffuses throughout blood 1.) Stroke: An occlusion of blood flow to ● e.g. occlusion of middle cerebral artery ○ Survival of patient ○ Postmortem analysis shows dead and absorbed tissue 2.) Cerebral Hemorrhage ● Post mortem coronal section following cerebral hemorrhage ● Dorsomedial region of left hemisphere was destroyed ● Also note lesion in temporal region of right hemisphere—due to cerebrovascular accident (CVA) two years prior to death. ○ If a neuron does not receive nutrients that pass through astrocytes of blood brain barrier, then (inter alia) SodiumPotassium Pumps (need ATP) will not be able to restore equilibrium or resting potentials, such that a disruption of cellular function (and likely apoptosis) will likely take place. Degenerative Disorders ● Progressively worsen in individuals and subjects ● Ventricle enlargement in Huntington’s Disease (leading to damage of GABA-ergic Basal Ganglia cells) and in Schizophrenia ● Tissue (viz. cortical) degeneration of tissue in Alzheimer’s Disease (Beta-Amyloid senile plaques and neurofibrillary entanglements with Tau, a Microtubule-Associated Protein, MAP) ● Parkinson’s notably leads to degeneration of basal ganglia (e.g. striatum, substantia nigra) and motor cortex, resulting in degeneration of dopaminergic neurons and subsequent motor inhibition Alzheimer’s Disease ● Normal vs. Alzheimer’s patient (slide)

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White matter growth is emerging, usually around medial temporal lobe ○ Evidenced particularly within MRI scans Traumatic Brain Injury (TBI) ● Trauma can lead to extensive destruction of neural tissue ● Coups (primary impact of brain with skull from collision) & Countercoups (subsequent rebounding from inner skull to collision of opposite brain region with skull) ○ Susceptible due to presence of cerebrum/brain within volume of CSF ○ Particularly harmful due to jagged edges and surfaces of the inner skull, particularly orbital region ● Other areas are vulnerable susceptible as well ○ e.g. occipital and temporal lobes ● Critical Experimental Example: A. Holbourn of Oxford (1943) ○ Researcher filled skull with gelatin and violently gyrated the skull ○ Most of gelatin model remained intact, but orbitofrontal region (involved with decision making and impulse control) suffered damage Traumatic Brain Injury (example) ● Orbital region of skull is convoluted ● Violent shaking of brain from impact can cause lesions ● Patient suffered injury 24 years prior to death ● Injury results in intellectual deterioration ○ You can help TBI survivors in wellness projects each week with Neuro Nights, a collaboration with BRAIN, the CBI association of Ohio State, and the Martha Morehouse Outpatient Center. Thursdays, @6:30 pm on Zoom ○ Visit go.osu.edu/neuronights for more information)

Epilepsy ● Disruption to Neural Signaling and Action Potentials (not necessarily to tissue) ● Sometimes seizures are subtle (petit mal seizure) or more profound (grand mal seizure) ● Can be gauged or confirmed by EEG (Electroencephalography) Brain-Behavior Relationships following Neural Disruption ● Logic: if a structure contributes to a task , then a dysfunctional structure should impair performance on that task ● Historical limitations: Limited Information on Extent of Damage, and Location (§ L-IN-E over Damage and Location) Next Lecture: Continuing on Chapter 3; starting with Single vs. Double Dissociations (Very Critical for Neuroscience Studies)...