Latest Pedagogical Preprints

Sleep is a fundamental and universal biological process that governs the physical, cognitive, and emotional well-being of virtually every living organism. Despite occupying approximately one-third of the human lifespan, sleep remains among the least understood physiological phenomena in the life sciences. This article provides a comprehensive overview of the science of sleep as presented in an introductory psychology context. Beginning with an examination of biological rhythms---circadian, circa-tidal, circalunar, and circannual---the discussion progresses to the neural mechanisms that regulate sleepiness, with particular emphasis on the suprachiasmatic nucleus (SCN) and the role of melatonin. The architecture of a healthy night of sleep is analyzed through the lens of electroencephalographic (EEG) recordings, distinguishing rapid eye movement (REM) sleep from the multiple stages of non-rapid eye movement (NREM) sleep. The article further examines how sleep changes across the lifespan, explores prominent theories of the functions of sleep and dreaming, and reviews clinically significant sleep disorders including insomnia, sleepwalking, sleep apnea, and the rare but lethal fatal familial insomnia (FFI). The article concludes by situating sleep research within the broader framework of consciousness studies and identifies open questions that represent promising directions for future inquiry.

Movement can fail in qualitatively distinct ways depending on which component of the motor system is disrupted. This article provides a systematic account of the neural systems supporting voluntary action and the disorders that arise from their dysfunction. Five dimensions of motor impairment are distinguished: failure to generate force, failure to organise a learned action, failure to initiate and scale movement, failure to coordinate movement components, and the intrusion of unwanted activity. Parkinson's disease serves as the primary clinical exemplar, examined through the lens of dopaminergic circuit dysfunction, pharmacological and surgical intervention, and rehabilitation strategies. Contrasting conditions---including amyotrophic lateral sclerosis, Huntington's disease, dystonia, essential tremor, cerebellar ataxia, limb apraxia, and acquired apraxia of speech---are discussed to illustrate how different network disruptions produce different observable syndromes. Cerebellar contributions to prediction, adaptation, and motor learning are addressed alongside the limitations of forward-model accounts. Phantom limb phenomena are presented as evidence for the representational nature of body experience. Throughout, a methodological principle is emphasised: description of the impairment must precede localisation, and localisation must precede causal inference. Accurate phenomenological characterisation is the foundation of both clinical assessment and mechanistic understanding.

Ethnocentrism, broadly defined as the tendency to evaluate other cultures according to the standards and values of one's own culture, represents one of the most pervasive yet underexamined forces shaping human cognition, social behavior, and scientific inquiry. This article, derived from a guest lecture delivered in an introductory psychology course, explores the psychological foundations of ethnocentrism, tracing its origins in basic cognitive processes such as social categorization and socialization, and examining how it can escalate into stereotyping, prejudice, and, in its most extreme form, racism. Particular attention is paid to the distinction between explicit and implicit bias, including the methodological challenges inherent in studying unconscious attitudes. The article further introduces linguistic markers---specifically accent---as an often overlooked yet powerful cue that individuals use to distinguish in-group from out-group members. Drawing on research in both psychology and applied linguistics, including accent bias studies conducted in Pacific educational settings, this overview argues that recognizing and studying ethnocentric tendencies, whether overt or subconscious, is an essential step toward building more equitable societies and producing more methodologically rigorous psychological research.

Biopsychology (biological psychology) investigates how mental life and behavior emerge from biological systems, especially the nervous system. These lecture notes provide an integrated introduction suitable for students and the general public, emphasizing foundational neuroanatomy, neuronal communication, hemispheric specialization, and the logic and limitations of brain-imaging methods. Using common misconceptions (e.g., the claim that humans use only \(\approx 10\%\) of the brain) as an entry point, the notes develop a coherent account of brain energetics, cellular maintenance, and network-level computation. They then examine the neuron as the fundamental signaling unit and synaptic transmission as the mechanism by which learning modifies functional connectivity. Case-based evidence is highlighted through split-brain surgery outcomes, which reveal dissociations between verbal report and perceptual-motor processing and motivate the concept of a left-hemisphere ``interpreter'' that constructs post hoc narratives. Finally, the notes compare major imaging modalities in terms of spatial and temporal resolution, underscoring why methodological constraints shape theoretical claims, and discuss emerging whole-brain recording approaches in model organisms. The overarching goal is to cultivate biologically grounded psychological reasoning: mental processes are not disembodied faculties but activities of living tissue organized into systems that operate continuously, economically, and adaptively.

Language is a core human capacity supported by distributed neural systems that enable comprehension, production, repetition, reading, and writing. Disruption to these systems produces clinically meaningful language disorders that vary in symptom profile, anatomical correlates, prognosis, and rehabilitation needs. This article synthesizes a practical neuropsychological framework for understanding language dysfunctions, using classical aphasiology as an organizing scaffold while incorporating contemporary clinical realities. We distinguish major aphasia syndromes---including Broca's aphasia, Wernicke's aphasia, conduction aphasia, and anomic aphasia---by emphasizing three clinically decisive dimensions: fluency, comprehension, and repetition. We further differentiate aphasia from apraxia of speech, a motor planning disorder that impairs articulation without necessarily compromising linguistic competence. The article reviews historical foundations (including associationist models of language and hemispheric lateralization), outlines lesion--symptom mapping with attention to the perisylvian network (inferior frontal gyrus, posterior superior temporal cortex, inferior parietal regions, and connecting white matter pathways), and provides guidance on bedside and formal assessment strategies. We also describe the complementary roles of neuroimaging (CT and MRI) and behavioral testing in etiological diagnosis and functional characterization. Finally, we discuss recovery trajectories in stroke, traumatic brain injury, and neurodegenerative disease, highlighting time-sensitive acute care, early spontaneous recovery, longer-term therapy-driven gains, and the constraints imposed by progressive pathology. The result is a set of lecture-based scholarly notes intended to support students, clinicians-in-training, and informed members of the public in interpreting language symptoms as indicators of underlying brain dysfunction and in reasoning about assessment and recovery.

Attention-Deficit/Hyperactivity Disorder (ADHD) is commonly presented either as a straightforward neurodevelopmental disorder best addressed by diagnosis and treatment, or as a socially constructed label that primarily serves institutional interests. Both framings capture partial truths while obscuring the deeper ethical question at stake: how diagnostic language reorganizes authority, responsibility, and the architecture of choice in education and work. Using the critical tradition associated with Thomas Szasz as a springboard, these lecture notes develop an academically grounded framework for discussing ADHD that (i) distinguishes clinical utility from political and institutional consequences of medicalization, (ii) clarifies the normative nature of diagnostic thresholds on continuous trait distributions, (iii) integrates evolutionary ``mismatch'' perspectives to contextualize attentional and motivational styles, and (iv) derives policy-relevant implications for universities and workplaces, including universal design, needs-based accommodations that reduce dependence on diagnostic credentials, and robust informed-consent norms. The central claim is not that ADHD is unreal or that treatment is illegitimate, but that defaulting to medicalized solutions as the primary administrative lever risks eroding autonomy and narrowing acceptable cognitive diversity. A humane and scientifically responsible response requires parallel investment in environmental redesign, pedagogical pluralism, and procedural safeguards that keep the person---rather than the institution---as the primary locus of decision-making.

Perception begins as physics: structured energy and matter in the environment interact with biological receptors, are transduced into neural signals, and are ultimately interpreted as conscious percepts. This article develops lecture notes on the physics of perception for an upper-level Sensation and Perception course. The central aim is to specify what, exactly, sensory systems detect---not in terms of subjective experience alone, but in terms of measurable physical variables that reach the body and can be transformed into neural codes. We articulate a three-stage analysis that helps resolve classic philosophical puzzles (e.g., the ``tree falling in a forest'') by separating (i) events in the physical world, (ii) the subset of those events that can in principle be detected by a given organism, and (iii) the organism's perceptual experience and report. We then survey core forms of environmental energy relevant to human sensation: electromagnetic radiation (vision), mechanical pressure waves (audition), mechanical and thermal interactions at body surfaces and within tissues (somatosensation, proprioception, vestibular function), and chemical structures dissolved in liquids or suspended in air (gustation and olfaction). Throughout, we emphasize that receptor systems are adaptive sampling devices: they restrict access to only a narrow band of the physical world and introduce lawful distortions (amplification, attenuation, compression, nonlinearities) that support behavioral goals rather than veridical recording. We integrate foundational psychophysics (absolute thresholds, just noticeable differences, psychometric functions, Weber fractions) and decision-theoretic signal detection theory (detection as inference under uncertainty) as methodological bridges between physics and experience. Finally, we discuss the epistemic implications of sensory envelopes for evaluating extraordinary perceptual claims and for understanding why perception is reliable enough for survival yet systematically limited and biased.

Psychology’s modern history can be read as a sequence of changing answers to a deceptively simple question: What, exactly, is psychology allowed to study? From the late nineteenth century onward, the field repeatedly redrew its boundaries in response to conceptual disputes and methodological constraints. This lecture-based article offers an integrative narrative of major historical inflection points: Wundt’s laboratory psychology and the attempt to render consciousness measurable; early introspectionist programs and their internal tensions; Freud’s proposal of unconscious motivation and conflict; Jung’s expansion toward symbolic, cultural, and potentially transpersonal layers of mind; behaviorism’s rejection of mentalistic explanation in favor of observable stimulus--response relations and operant learning; Piaget’s developmental constructivism and the claim that children’s “wrong” answers reveal coherent cognitive structures; Eysenck’s psychometric and experimental critique of psychoanalysis and his insistence on measurement, prediction, and falsifiability in personality science; and Festinger’s cognitive dissonance theory as a paradigm for studying belief revision under social and motivational pressures. Throughout, the guiding theme is not date memorization but the evolution of permissible questions, accepted evidence, and dominant paradigms. The article concludes by situating contemporary cognitive neuroscience as a powerful, though historically contingent, synthesis that still grapples with enduring challenges: the privacy of subjective experience, the interpretation of correlational evidence, and the philosophical implications of explaining agency through mechanisms.

The term \emph{disorder} is ubiquitous in clinical psychology, psychiatry, and neuropsychology, yet its conceptual basis is frequently assumed rather than argued. This paper develops lecture-style notes for PSYC 3910 (Brain Dysfunction and Recovery) that place the question ``What is a disorder?'' prior to specific neuropsychological syndromes. Using classic debates in the philosophy of psychiatry and instructive neurological case phenomena (e.g., anosognosia, somatoparaphrenia, amnesia, delusional misidentification, phantom limbs), the notes distinguish description from explanation, observation from inference, and mechanistic account from moral judgment. The central aim is methodological: to cultivate disciplined skepticism toward both uncritical medicalization (the fallacy that naming a pattern explains it) and skeptical dualism (the fallacy that value-laden boundaries imply a lack of biological basis). The paper proposes a practical framework for evaluating disorder claims: (i) specify the target phenomenon, (ii) clarify the normative standard invoked, (iii) separate impairment, distress, and social deviance, (iv) identify the evidential bridge from brain observations to dysfunction claims, and (v) articulate potential falsifiers. Finally, it argues that neuropsychology’s greatest pedagogical contribution is not a catalog of deficits but a logic of inquiry: natural experiments reveal the normally invisible computational and representational work of the nervous system, thereby reframing ``what is wrong?'' into ``what must the intact system do to make ordinary experience possible?''

This paper examines the fundamental principles of nutrition, diet, and chrononutrition within the context of health psychology, tracing the evolutionary trajectory of human dietary patterns from hunter-gatherer societies to modern industrialized food systems. The analysis encompasses the critical evaluation of nutritional science, particularly examining methodological flaws in dietary research exemplified by the diet-heart hypothesis controversy. The paper explores energy balance principles, the historical transition from foraging to farming, and the implications of industrialized food production on human health outcomes. Special attention is given to chrononutrition, the timing of food intake, and its relationship to circadian rhythms. Through critical examination of case studies, including the work of Ancel Keys and subsequent challenges to established dietary guidelines, this paper highlights the importance of scientific rigor in nutritional research and the potential consequences of institutional bias in dietary recommendations. The discussion emphasizes the need for evidence-based approaches to nutrition that account for human physiological evolution and individual dietary variability.

Stress is often discussed as if it were inherently pathological, purely psychological, and eliminable through willpower or environmental change. Health psychology, however, emphasizes that stress is an evolutionarily ancient, physiologically instantiated, and generally adaptive response that supports survival by coordinating rapid behavioral and metabolic reconfiguration. This manuscript develops a set of lecture notes that treat stress, distress, crisis, trauma, and suicidal behavior as points along a continuum of increasing dysregulation---that is, increasingly costly ``failure modes'' of an otherwise protective system. Beginning with foundational definitions, the paper integrates autonomic nervous system dynamics, hypothalamic--pituitary--adrenal (HPA) axis physiology, and cognitive appraisal mechanisms to clarify why stress cannot be eliminated, why it is not merely ``in the mind,'' and why it commonly generalizes across life domains. We then propose a conceptual sequence: adaptive stress as problem-focused mobilization; distress as the failure of available coping strategies; crisis as disruption of core expectations and world-models; trauma as unresolved or repeatedly reactivated crisis leading to persistent prediction errors and hypervigilance; and suicide as a potential end-stage solution attempt when suffering becomes appraised as inescapable. The framework is situated within the health psychology perspective that focuses on population-level determinants and prevention through systemic redesign, particularly in contexts of evolutionary mismatch where symbolic and chronic stressors outpace the recovery capacities shaped by ancestral environments. Practical implications are offered for education, work design, social support infrastructures, and time-sensitive suicide prevention strategies.

Visuospatial disorders occupy a central position in neuropsychology because they expose a fundamental fact about the visual system: seeing is not equivalent to the registration of photons on the retina, but rather a multi-stage construction that integrates sensory coding, selective attention, spatial representation, memory, and action planning. This paper develops lecture-based notes on visuospatial disorders, using clinical syndromes as a framework for understanding visual processing and consciousness. After reviewing the functional anatomy and temporal dynamics of visual pathways---from retina to subcortical relays (e.g., lateral geniculate nucleus and pulvinar) and onward to primary visual cortex and distributed cortical streams---we examine major disorders that dissociate visual sensation, recognition, and awareness. Emphasis is placed on unilateral spatial neglect as a disorder of spatial attention and representation, visual agnosias as impairments of object recognition (classically linked to ventral-stream dysfunction), and blindsight as a striking dissociation in which visually guided behavior can occur without reported awareness, often following lesions of primary visual cortex. The discussion integrates bedside and laboratory assessment methods (copying tasks, line bisection and cancellation tests, forced-choice paradigms), lesion patterns and laterality, prognostic factors following stroke, and rehabilitation approaches including strategy training and prism adaptation. Beyond clinical relevance, these syndromes provide empirical constraints on theories of consciousness by demonstrating that awareness depends on recurrent and distributed processing rather than a single ``visual center.'' The paper concludes with implications for neuropsychological assessment, patient education, and public health contexts where cerebrovascular disease is prevalent.