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The Experimental Methods of Cognitive Psychology Windows to Mind Dipanjan Ray [email protected] Department of Psychology, Ashoka University August 29, 2024  Overview Overview Points to be covered 1. Controlled laboratory experiments 2. Natur...

The Experimental Methods of Cognitive Psychology Windows to Mind Dipanjan Ray [email protected] Department of Psychology, Ashoka University August 29, 2024  Overview Overview Points to be covered 1. Controlled laboratory experiments 2. Naturalistic observations 3. Virtual reality 4. Case studies 5. Self report 6. Eye tracking 7. Neuroimaging 7.1 Electroencephalography (EEG) 7.2 Functional Magnetic Resonance Imaging (fMRI) Dipanjan Ray · Experimental Methods · August 29, 2024 2 / 55  Tools Controlled Laboratory Experiments Controlled Laboratory Experiments A hypothesis is addressed by running an experiment in which the independent variable of interest is manipulated and the effect of the manipulation is assessed by measuring the dependent variables ( e.g., response time, the percentage of correct responses, the type of errors made and so on). Obtain samples of performance at a particular time and space. Dipanjan Ray · Experimental Methods · August 29, 2024 3 / 55  Tools Controlled Laboratory Experiments Controlled Laboratory Experiments: Example Sternberg’s experiment (1966) Hypothesis: We access the content of our short term memory serially/ simulataneously? Independent Variables: Size of memory set Whether followed by target/foil Dependent Variable: Reaction time Dipanjan Ray · Experimental Methods · August 29, 2024 4 / 55  Tools Controlled Laboratory Experiments Controlled Laboratory Experiments: Example Sternberg’s experiment (1966) Figure: Results Dipanjan Ray · Experimental Methods · August 29, 2024 5 / 55  Tools Controlled Laboratory Experiments Controlled Laboratory Experiments: Example Sternberg’s experiment (1966) Figure: Sternberg’s analysis of the sequence of information-processing stages in his task Dipanjan Ray · Experimental Methods · August 29, 2024 6 / 55  Tools Controlled Laboratory Experiments Controlled Laboratory Experiments: Strengths and Weaknesses Strengths: Easy to administer, score, and do statistical analysis Weaknesses: Difficulty in generalizing results beyond a specific time, place, and task settings. Discrepancies between behaviour in real life and in the laboratory (low ecological validity). Dipanjan Ray · Experimental Methods · August 29, 2024 7 / 55  Tools Controlled Laboratory Experiments Controlled Laboratory Experiments: Some factors contributing to low ecological validity 1. In controlled lab experiments, test environments are designed to reduce distractions, confusion, and fatigue. 2. Cognitive studies routinely employ abstract or arbitrary stimuli, such as using paired colours to establish stimulus-response rules, that bear very little resemblance to real-world elements. 3. Individuals behave differently when being observed vs when not. Dipanjan Ray · Experimental Methods · August 29, 2024 8 / 55  Tools Controlled Laboratory Experiments Low Ecological Validity: Example Imagine a research study simulating a plane crash where participant adrenaline levels, heart rate, and ability to follow instructions afterwards were recorded as they experienced a simulation of the phases of a plane crash. Although participants had higher levels of adrenaline and high heart rates, they were still able to follow instructions after the simulation. When studied outside of the controlled simulation environment, for example, during a real crash, the results were not accurate. Individual’s did have higher heart rates and adrenaline rates, but they could not follow instructions 1. 1 Source: https://study.com/learn/lesson/ecological-validity- significance-examples.html Dipanjan Ray · Experimental Methods · August 29, 2024 9 / 55  Tools Naturalistic Observations Naturalistic Observations Observe real-life situations, as in classrooms, work-settings, and homes. Dipanjan Ray · Experimental Methods · August 29, 2024 10 / 55  Tools Naturalistic Observations Naturalistic Observations Strengths: Access to rich contexual information Weaknesses: Lack of experimental control Dipanjan Ray · Experimental Methods · August 29, 2024 11 / 55  Tools Case Studies Case Studies Engage in intensive study of single individuals, drawing general conclusions about behavior. Dipanjan Ray · Experimental Methods · August 29, 2024 12 / 55  Tools Case Studies Case Studies Strengths: Access to detailed information about individuals, including historical and current contexts. May lead to specialized applications for special groups (e.g., prodigies, persons with brain damage) Weaknesses: Limited generalizability due to small sample size and nonrepresentativeness of sample Dipanjan Ray · Experimental Methods · August 29, 2024 13 / 55  Tools Case Studies Louis Victor Leborgne (“Tan Tan”) Dipanjan Ray · Experimental Methods · August 29, 2024 14 / 55  Tools Case Studies The Curious Case of Phineas Gage (1823-1860)! “He is fitful, irreverent, indulging at times in the grossest profanity (which was not previously his custom), manifesting but little deference for his fellows, impatient of restraint or advice when it conflicts with his desires.... A child in his intellectual capacity and manifestations, he has the animal passions of a strong man.... His mind was radically changed, so decidedly that his friends and acquaintances said he was ‘no longer Gage.” a a Harlow JM. Recovery from the passage of an iron bar through the head. Publ Mass Med Soc. 1868;2:327–347. Dipanjan Ray · Experimental Methods · August 29, 2024 15 / 55  Tools Self Reports Self Reports Obtain participants’ reports of own cognition in progress or as recollected. Examples: Verbal protocols, self-rating, diaries. Dipanjan Ray · Experimental Methods · August 29, 2024 16 / 55  Tools Self Reports Self Reports Strengths: Access to introspective insights from participants’ point of view. Weaknesses: May influence cognitive process being reported Dipanjan Ray · Experimental Methods · August 29, 2024 17 / 55  Tools Eye Tracking Eye Tracking Measures either the point of gaze (where one is looking) or the motion of an eye relative to the head. Dipanjan Ray · Experimental Methods · August 29, 2024 18 / 55  Tools Eye Tracking Eye Tracking Dipanjan Ray · Experimental Methods · August 29, 2024 19 / 55  Tools Eye Tracking Eye Tracking Dipanjan Ray · Experimental Methods · August 29, 2024 20 / 55  Tools Eye Tracking Eye Tracking Dipanjan Ray · Experimental Methods · August 29, 2024 21 / 55  Tools Eye Tracking Eye Tracking Dipanjan Ray · Experimental Methods · August 29, 2024 22 / 55  Tools Neuoimaging Electroencephalography (EEG) EEG measures electrical activity generated by the synchronized activity of thousands of neurons using small, metal discs (electrodes) attached to the scalp Dipanjan Ray · Experimental Methods · August 29, 2024 23 / 55  Tools Neuoimaging Electroencephalography (EEG) Epileptic spike and wave discharges monitored EEG Dipanjan Ray · Experimental Methods · August 29, 2024 24 / 55  Tools Neuoimaging Electroencephalography (EEG) Event Related Potential An event-related potential (ERP) is the measured brain response that is the direct result of a specific sensory, cognitive, or motor event. More formally, it is any stereotyped electrophysiological response to a sensory/cognitive/motor event. Example: N100, P300 Dipanjan Ray · Experimental Methods · August 29, 2024 25 / 55  Tools Neuoimaging Electroencephalography (EEG) P300 Typically elicited during an oddball target detection task by infrequently presented salient stimuli interspersed among frequent standard stimuli Dipanjan Ray · Experimental Methods · August 29, 2024 26 / 55  Tools Neuoimaging Electroencephalography (EEG) P300 The P300 is a positive voltage deflection in the stimulus-locked ERP occurring 300 milliseconds after the stimulus. Dipanjan Ray · Experimental Methods · August 29, 2024 27 / 55  Tools Neuoimaging Electroencephalography (EEG) P300: Application in locked-in syndrome A rare and serious neurological disorder that happens when a part of your brainstem is damaged, usually from a stroke. People with LiS have total paralysis but still have consciousness and their normal cognitive abilities. Brain computer interface Dipanjan Ray · Experimental Methods · August 29, 2024 28 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis Power spectrum and spectrogram of a sinusoidal wave of single frequency 2. 2 Ng, M. C., Jing, J., Westover, M. B. (2019). Atlas of intensive care quantitative EEG. Springer Publishing Company. Dipanjan Ray · Experimental Methods · August 29, 2024 29 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis Power spectrum and spectrogram of two summed sinusoidal waves 3. 3 Ng, M. C., Jing, J., Westover, M. B. (2019). Atlas of intensive care quantitative EEG. Springer Publishing Company. Dipanjan Ray · Experimental Methods · August 29, 2024 30 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis EEG Waves Dipanjan Ray · Experimental Methods · August 29, 2024 31 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis Power spectrum and spectrogram of posterior dominant rhythm (PDR) in the alpha frequency range, and a "slow-wave" EEG. 4. 4 Ng, M. C., Jing, J., Westover, M. B. (2019). Atlas of intensive care quantitative EEG. Springer Publishing Company. Dipanjan Ray · Experimental Methods · August 29, 2024 32 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis Experimental Paradigms 5. 5 Bogaerts et al., 2021 Dipanjan Ray · Experimental Methods · August 29, 2024 33 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis Spectrogram 6. 6 Bogaerts et al., 2021 Dipanjan Ray · Experimental Methods · August 29, 2024 34 / 55  Tools Neuoimaging Electroencephalography (EEG) Spectral Analysis Change in beta power with trials 7. 7 Bogaerts et al., 2021 Dipanjan Ray · Experimental Methods · August 29, 2024 35 / 55  Tools Neuoimaging Electroencephalography (EEG) Strengths: The ability to see brain activity as it unfolds in real time, at the level of milliseconds (thousandths of a second). Weaknesses: It’s hard to figure out where in the brain the electrical activity is coming from. Dipanjan Ray · Experimental Methods · August 29, 2024 36 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Dipanjan Ray · Experimental Methods · August 29, 2024 37 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Dipanjan Ray · Experimental Methods · August 29, 2024 38 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Figure: From neural activation to BOLD signal8 8 Source: Internet Dipanjan Ray · Experimental Methods · August 29, 2024 39 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Hemodynamic Response Function Dipanjan Ray · Experimental Methods · August 29, 2024 40 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Dipanjan Ray · Experimental Methods · August 29, 2024 41 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Cognitive Subtraction Dipanjan Ray · Experimental Methods · August 29, 2024 42 / 55  Tools Neuoimaging Example (Buchweitz et al., 2009) Dipanjan Ray · Experimental Methods · August 29, 2024 43 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Strengths: Good spatial resolution. Weaknesses: Poor temporal resolution. Dipanjan Ray · Experimental Methods · August 29, 2024 44 / 55  Tools Neuoimaging Functional Magnetic Resonance Imaging (fMRI) Precautions Neural correlates of interspecies perspective taking in the post-mortem Atlantic Salmon:Craig M. Bennett et al., 2009 Dipanjan Ray · Experimental Methods · August 29, 2024 45 / 55  Tools Neuoimaging Integration of information in Brain Brain Networks Dipanjan Ray · Experimental Methods · August 29, 2024 46 / 55  Tools Neuoimaging Correlation Dipanjan Ray · Experimental Methods · August 29, 2024 47 / 55  Tools Neuoimaging Autism and brain connectivity Supekar et al., 2013 Dipanjan Ray · Experimental Methods · August 29, 2024 48 / 55  Tools Neuoimaging Alzheimer’s disease and brain connectivity Wang et al., 2015 Dipanjan Ray · Experimental Methods · August 29, 2024 49 / 55  Tools Neuoimaging Problem with correlation Dipanjan Ray · Experimental Methods · August 29, 2024 50 / 55  Tools Neuoimaging Problem with correlation Dipanjan Ray · Experimental Methods · August 29, 2024 51 / 55  Tools Neuoimaging Granger Causality Dipanjan Ray · Experimental Methods · August 29, 2024 52 / 55  Tools Neuoimaging Aging and directed connectivity Das et al., 2020 Dipanjan Ray · Experimental Methods · August 29, 2024 53 / 55  Tools Neuoimaging Depression and effective connectivity Dipanjan Ray · Experimental Methods · August 29, 2024 54 / 55 Thank You for Your Attention!