Psychology Ch. 4

Androgens

Masculinizing hormones, including testosterone.

Electroencephalogram

Microscopic needle electrodes are inserted into the brain to measure brainwaves and neural activity.

Neurons

Nerve cells that make up the nervous system. Transmit info to, from, and within the CNS.

Adrenal Hormones

Produced in adrenal glands. Involved in emotion and stress. Respond to heat, cold, injury, burns, etc.

Myelin Sheath

Protective coating that surrounds each axon.

Peripheral Nervous System

All portions of the nervous system, outside of the brain and spinal cord. Handles CNS input & output.

Sympathetic Nervous System

Branch of Autonomic NS. Mobilizes bodily resources and increases energy output during emotion and stress. (Ex: blush, sweat, increased heart rate.)

Parasympathetic Nervous System

Branch of Autonomic NS. Operates during relaxed states and conserves energy. Acts like pressure on a brake, relaxing nerves.

Dendrites

Branches that receive info from other neurons and transmit it toward the cell body.

Action Potential

Brief change in electrical voltage that occurs between inside and outside of an axon when a neuron is stimulated. Serves to produce electrical impulse.

Sensory Nerves

Carry messages from receptors on skin, muscles, etc.

Motor nerves

Carry orders from CNS to muscles, glands, and organs. Enable us to move and contract/secrete hormones.

Neurotransmitters

Chemical substances released by transmitting neuron at synapse that alter activities of receiving neuron. Make it possible to excite or inhibit another neuron. Dangerous for levels of these to be too high or too low.

Hormones

Chemical substances that affect the functioning of other organs; secreted by glands. Released into bloodstream and carried variable distance to destination. Variety of functions.

Cell Body

Contains biochemical machinery for keeping the neuron alive. Determines whether it should "fire" info to other neurons.

Progesterone

Contributes to growth and maintenance of uterine lining in preparation for fertilized egg.

Cerebellum

Contributes to sense of balance and coordination. Plays role in memory, solving problems, understanding words, and motor tasks.

Thalamus

Deep in brain's interior. Relays motor impulses from higher brain center to spinal cord. Relays sensory messages to higher centers. "Traffic officer" of the brain.

Axons

Extending fibers that conduct impulses away from the cell body and transmit them to other neurons.

Spinal Cord

Extension of the brain that acts as bridge between the brain and parts of the body.

Estrogens

Femininzing hormones.

Frontal Lobes

Front part of the brain. Contain the motor cortex. The Broca's area (left frontal lobe) handles speech production. Also involved with emotion, planning, creative thinking, taking initiative, social judgment, and short-term memory. Prefontal cortex is related to personality.

Left

Hemisphere involved with processing language; logical, symbolic, sequential tasks; solving math problems; rationale & analytic cognition; speech production; Controls right side of the body.

Right

Hemisphere involved with spatial-visual ability; facial recongition; creativity and artistic apprecation; processing nonverbal sounds; intuition and holistic cognition; processing fear and sadness; controlling left side of the body.

Pons

Involved in sleeping, waking, dreaming. Part of brain stem.

Lesion method

Involves damaging/removing sections of an animal's brain and observing the effects.

Cerebrum

Largest brain structure, divided into 2 cerebral hemispheres. Connected by corpus callosum. Made up of 4 distinct lobes.

Occipital Lobes

Lower back part of brain. Contains visual cortex.

Reticular Activating System

Network of neurons that connects with higher brain areas. Screens incoming info and demands that things get done. Helps us stay conscious and alert.

Phrenology

Notion that brain has many areas that are meant to serve many various and diverse functions. (Joseph Gall)

Hypothalamus

Par of the Limbic system. Located below the thalamus. Involved in natural drives associated with the species (hunger, thirst, sex). Contains a biological clock regulating body rhythms. Pituitary gland hangs from here.

Somatic Nervous System

Part of PNS. Connects to sensory receptors and to skeletal muscles. Permits voluntary action.

Autonomic Nervous System

Part of PNS. Regulates internal organs and glands.

Amygdala

Part of the Limbic system. Evaluates sensory info, determines emotional importance, and contributes to decision to approach or withdraw from situation.

Hippocampus

Part of the Limbic system. Looks like seahorse. Compares sensory info with info the brain has already stored. The "gateway to memory."

Brain Stem

Part of the brain at the top of the spinal cord.

Transcranial Magnetic Stimulation

Places coil wire over one's head and delivers large current, producing powerful magnetic field. Causes neurons to fire. Can also be used to inactivate an area for observation of behavior.

Central Nervous System

Portion of the nervous system consisting of the brain and spinal cord. Receives, processes, interprets, and stores incoming sensory info. Sends out messages destined for muscles, glands, and internal organs.

Magnetic Resonance Imaging

Powerful magnetic fields and radio frequencies produce vibrations in nuclei of atoms. Vibrations are measured as signals. Used to study body and brain tissue.

PET scan

Records and analyzes biochemical changes in brain as they are happening. Subjects are injected with radioactive substance that accumulates in active brain areas. The radiation emission is detected by scanning device.

Medulla

Responsible for autonomic functions such as breathing and heart rate.

Sex Hormones

Secreted by gonads and adrenal glands.

Melatonin

Secreted by pineal gland; regulates biological rhythms and promotes sleep.

Temporal Lobes

Sides of the brain. Involved in memory, perception, emotion. Contain auditory cortex. Wernicke's area (in left temporal lobe) is involved with language comprehension.

Endorphins

Similar in structure to opiates; involved in pain reduction, pleasure, and memory. Can limit or prolong effects of neuronal activities. Levels increase during fear or stress.

Synapse

Site where nerve impulses are transmitted to another nerve cell. Made up of axon terminal, synaptic cleft, and receptor sites in receiving cell.

Glial Cells

Support, nurture, and insulate neurons; help regulate neuronal functioning.

Axon Terminals

Tips of axons. Location where neurons transmit info to the dendrite of another neuron.

Parietal Lobes

Top part of brain. Contain somatosensory cortex, which receives info about pressure, pain, touch, and temperature.