Unit 2: Vocab

Epigenetics

The study of heritable changes in gene function that do not involve alterations in the DNA sequence.

Behavioral Genetics

The study of genetic and environmental influences on behavior in a population.

Heritability

The proportion of variability in a population that can be attributed to genetic factors.

Shared Environmental Influences (Es)

Experiences shared by all members of a family.

Non-shared Environmental Influences (ENS)

Environmental influences that are unique to each individual and not shared by other members of the family.

Monozygotic (MZ) Twins

Identical twins that developed from a single fertilized egg.

Dizygotic (DZ) Twins

Fraternal twins that developed from two separate fertilized eggs.

Sensation

The detection of physical stimuli and the analysis of elementary stimulus properties.

Perception

Higher-order analysis, synthesis, and interpretation of sensations.

Adequate Stimulus

The type of stimulus to which a specific sensory receptor is most sensitive.

Transduction

The process by which sensory receptors convert stimulus energy into electrical signals (action potentials).

Thalamus

A relay center in the brain that transmits sensory information from various parts of the body to the cerebral cortex.

Binding Problem

The problem of how the brain combines information from different sensory modalities and features into a unified conscious experience.

Top-down Processing

Perceptual processing that is influenced by prior knowledge, expectations, and context.

Bottom-up Processing

Perceptual processing that begins with the sensory input from the environment.

Auditory Cortex

The region of the brain responsible for processing auditory information.

Tonotopic Organization

The spatial arrangement of neurons in the auditory system according to the frequencies of sounds to which they respond.

Somatosensation

The sense of touch, temperature, pain, and proprioception.

Cutaneous Receptors

Sensory receptors located in the skin that respond to touch, pressure, vibration, and temperature.

Stereognosis

The ability to identify objects by touch.

Proprioception

The sense of the relative position of one's own body parts and strength of effort being used in movement.

Nociception

The processing of noxious stimuli, which are associated with pain.

Dorsal-Column-Medial-Lemniscus System

A major somatosensory pathway that carries information about touch and proprioception.

Anterolateral Systems

Somatosensory pathways that primarily carry information about pain and temperature.

Decussate

To cross over to the opposite side.

Somatosensory Homunculus

A distorted representation of the human body in the somatosensory cortex, where the size of each body part is proportional to the amount of cortical area dedicated to processing sensory information from that part.

Astereognosia

The inability to recognize objects by touch, despite intact touch sensation.

Asomatognosia

The inability to recognize parts of one's own body.

Contralateral Neglect

A neurological disorder in which a person fails to attend to one side of space, typically the left side, often associated with damage to the right parietal cortex.

Anosmia

The inability to smell.

Ageusia

The inability to taste.

Selective Attention

The ability to focus on specific stimuli while ignoring others.

Cocktail Party Phenomenon

The ability to focus on a single auditory stimulus (like a conversation) while filtering out other background noise.

PPC (Posterior Parietal Cortex)

A brain region involved in spatial awareness and attention.

PFC (Prefrontal Cortex)

A brain region involved in executive functions, including top-down attention.

Simultagnosia

A neurological disorder characterized by the inability to perceive more than one object at a time.

Lateralization of Function

The tendency for some neural functions or cognitive processes to be specialized to one side of the brain or the other.

Corpus Callosum

A large bundle of nerve fibers that connects the left and right hemispheres of the brain.

Optic Chiasm

The point in the brain where the optic nerves from each eye partially cross over.

Split-brain Research

Studies conducted on patients who have had their corpus callosum surgically severed, often to treat severe epilepsy.

Helping Hand Phenomenon

An observation in split-brain patients where one hand (controlled by one hemisphere) interferes with the task being performed by the other hand (controlled by the other hemisphere).

Cross Cueing

A strategy used by split-brain patients where one hemisphere provides information to the other hemisphere through indirect means (e.g., a head movement).

Aphasia

An impairment of language, affecting the production or comprehension of speech and the ability to read or write.

Apraxia

A motor disorder caused by damage to the brain (specifically the parietal lobe) in which the individual has difficulty with motor planning to perform tasks or movements when asked, provided that the request or command is understood and the individual is willing to perform the task.

Broca's Area

A region in the frontal lobe of the dominant hemisphere, usually the left, with functions linked to speech production.

Wernicke's Area

A region in the brain concerned with the comprehension of language.

Arcuate Fasciculus

A bundle of nerve fibers that connects Broca's area and Wernicke's area.

Angular Gyrus

A region of the brain in the parietal lobe that is involved in processing language and numbers.

Critical Period (for Language)

A limited time frame during development when the brain is particularly receptive to learning language.

Plasticity of the Brain

The brain's ability to change and adapt throughout life.

Expressive Aphasia

Difficulty in producing spoken or written language, often associated with damage to Broca's area.

Receptive Aphasia

Difficulty in understanding spoken or written language, often associated with damage to Wernicke's area.