Neurodevelopmental and Brain Function Concepts: ASD, DSM, and Brain Localization

DSM

Diagnostic and Statistical Manual of Mental Disorders - provides classification system for mental disorders

ASD (Autism Spectrum Disorder)

A neurodevelopmental condition with disrupted development in social/communication deficits (SCDs) and repetitive sensory-motor behaviors/fixated interests (RRBs)

SCDs (Social and Communication Deficits)

Deficits in social-emotional reciprocity, nonverbal communication, and developing/maintaining relationships

RRBs (Restricted/Repetitive Behaviors or Interests)

Stereotyped/repetitive behaviors, adherence to routines, highly restricted interests, and atypical sensory responses

Savantism

Exceptional talent in one restricted area (common in ASD but not ubiquitous)

Spiky Profiles

Uneven cognitive profiles where a person is exceptional in some domains and unexceptional in others

Neurodiversity

A deviation from typical brain and behavior traits; variation in human brain/experience as natural diversity, not pathology

Neurotypical

A person whose brain/behavior falls within the typical range

Neurodivergent/Neurodiverse

A person whose brain/behavior falls outside or diverges from the typical range

Structural Stigma

Policies and practices of institutions that systematically restrict rights and opportunities for people with mental illnesses

Social Stigma (Public Stigma)

Phenomenon of social groups endorsing stereotypes about and acting against a stigmatized group

Self-Stigma (Internalized Stigma)

Negative feelings, maladaptive behavior, identity transformation, or stereotype endorsement resulting from experiences of negative social reactions based on mental illness

Four Ds - Disease

The biomedical mechanism for a condition is known

Four Ds - Disorder

Functional atypicality or disturbance at the organic level that is context-independent

Four Ds - Disability

Below average performance in a specific psychological/physical function

Four Ds - Difference

Atypical, but with no negative impact on functioning or wellbeing

Cartesian Dualism

Philosophy that the universe is composed of physical matter (body/brain) and the human mind (soul/spirit), which are separate

Conversion Disorder

Family of conditions with fixed beliefs of somatic dysfunction arising from psychological distress that produce patterns of loss or gain of function

Placebo Effect

Improvement in symptoms after a treatment with no therapeutic value (e.g., sugar pill)

Sham Surgery

Surgery that mimics a real surgery but omits the actual therapeutic step

Occam's Razor

The simplest solution is usually the correct one

Morgan's Canon

Animal activity should not be interpreted in terms of higher psychological processes if it can be interpreted in terms of lower processes

Panpsychism

View that consciousness, mind, or mentality is a fundamental and ubiquitous feature of reality

Asomatognosia

Acquired condition where an individual displays lack of awareness of parts of one side of their own body (typically left side, from right frontal/parietal lobe damage)

Somatoparaphrenia

Complication of asomatognosia with hallucinations that someone else's body part is attached to them

Infarct

Area of damage due to stroke

Homunculus/Homunculi

Map representation of the body on the brain's motor or sensory cortex (created by Wilder Penfield)

Mirror Self-Recognition (MSR) Test

Test where animals are marked while anesthetized to see if they recognize themselves in a mirror

Prefrontal Lobotomy

Surgical procedure severing connections to/from the prefrontal cortex, originally claimed to treat psychiatric conditions

Leucotome

Surgical instrument used to cut holes in the prefrontal cortex

Transorbital Lobotomy

Lobotomy variation using an ice-pick-like device hammered through the orbital socket

Depatterning

Cameron's treatment involving massive electroconvulsive shock therapy until patient reached state of incontinence and memory loss

Psychic Driving

Cameron's treatment placing patients in insulin-induced coma while playing tape recordings through headphones

Space-Time Image

Knowing where you are, how long you've been there, and how you got there

Hebb's Postulates

Learning depends on strengthening synaptic connections when neurons fire together ("cells that fire together wire together")

Cell Assembly

Clusters of synaptically-connected neurons whose connections are molded by experience to form a percept

Phase Sequence

Stream of consciousness resulting from activation of interlinked cell assemblies in sequences

Hypermale Model of Autism (Extreme Male Brain Theory)

Theory by Simon Baron-Cohen that autistic people show exaggeratedly male-typical brain characteristics independent of sex

Corpus Callosum

Bundle of nerve fibers connecting the left and right brain hemispheres (thinner in males and exaggeratedly thin in autistic people)

Power Law (Pareto's Distribution/Principle)

Principle that roughly 80% of effects come from 20% of causes

Mirror Neurons

Brain cells that activate when performing or observing an action

Direct Matching Hypothesis

Theory that mirror neurons allow action understanding by directly mapping observed actions onto the observer's own motor system

Broken Mirror Neuron Theory

Theory that mirror neurons are dysfunctional/different in autistic people, explaining social difficulties

Choice Advantage

Faster predictions when an actor can choose freely where to point (due to body language cues activating mirror neuron system)

STORM (Social Top-Down Response Modulation Theory)

Theory that the medial prefrontal cortex (mPFC) exerts top-down control over the mirror neuron system to modulate social responses

Psychosomatic Symptoms

Physical symptoms arising without conscious thought, as if the body has a mind of its own

Brain Centre Assumption

Assumption that cognition is subserved by discrete functional units in the brain

Phrenology

Discipline that sought to measure human capacities by measuring bumps on the skull

Broca's Area

Brain region associated with language production (though localization is imperfect)

Overlay Plot

Method creating a Venn diagram of multiple patients' lesion locations to infer functional localization

Bregma

Reference point where three skull suture lines meet, used for brain coordinates

Transcranial Magnetic Stimulation (TMS)

Non-invasive technique applying magnetic field to produce stimulation or reversible lesion

Transcranial Electrical Stimulation (tES)

Non-invasive technique applying electrodes to pass current through cortical areas

Transcranial Ultrasound Stimulation (tUS)

Non-invasive technique using array of ultrasonic speakers to converge sound waves at brain location

Diaschisis

Functional damage appearing distant from anatomical damage site

Differential Vulnerability

Different brain parts are unequally susceptible to stroke or injury

Cerebral Angiography

Contrast X-ray technique using iodine injection to visualize blood vessels

Computed Tomography (CT)

Imaging technique using X-rays from multiple angles processed by computer algorithm

MRI Quench

Rapid loss of superconductivity in MRI magnet causing magnetic field to disappear and helium coolant to vent

Voxel

Volumetric pixel in brain imaging (approximately 1mm³ in MRI)

Vegetative State (Unresponsive Wakefulness Syndrome)

Condition where patients appear awake but do not respond to external stimuli

Electroencephalography (EEG)

Technique placing electrodes on skull to measure electrical brain activity

Event-Related Potentials

Electric signals measured from skull after a stimulus

Mu Rhythm

Brain wave pattern observed when watching motor actions of others or thinking about performing motor actions

Functional Hyperaemia

Shunting of blood to active parts of the brain

PET (Positron Emission Tomography)

Imaging technique using radioactive isotopes to track brain activity

Fluorodeoxyglucose (FDG)

Radioactive tracer that cells uptake like glucose but cannot digest, accumulating in active cells

fMRI BOLD Response

Blood Oxygen Level Dependent Response - mixture of regional cerebral blood flow and oxygen metabolism

Oxyhaemoglobin

Oxygen-rich blood (diamagnetic - no magnetic properties)

Deoxyhaemoglobin

Oxygen-poor blood (paramagnetic - displays magnetic properties in magnetic field)

Mean Difference Image

Further step of spatial averaging across all participants' paired image subtractions

Epiphenomenon

Artifact or make-believe phenomenon

Default Mode Network

Set of brain structures typically recruited when individuals are told not to think about anything (resting state)

Intrinsic Functional Connectivity

Looking at correlations and activity patterns between different brain areas/structures over time during rest