Psychology cycle 5

Biological psychology

the scientific study of the links between biological and psychological processes

Neuron

a nerve cell; the basic building block of the nervous system

Dendrites

Branchlike parts of a neuron that are specialized to receive information.

Axon

the neuron extension that passes messages through its branches to other neurons or to muscles or glands

Myelin sheath

a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next

Action potential

a neural impulse; a brief electrical charge that travels down an axon

Refractory period

a period of inactivity after a neuron has fired

Threshold

the level of stimulation required to trigger a neural impulse

All-or-none response

a neuron's reaction of either firing (with a full-strength response) or not firing.

Synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

Neurotransmitters

chemical messengers that cross the synaptic gaps between neurons

Reuptake

a neurotransmitter's reabsorption by the sending neuron

Endorphins

"morphine within"—natural, opiate-like neurotransmitters linked to pain control and to pleasure.

Agonist

a molecule that, by binding to a receptor site, stimulates a response

Antagonist

A biological structure or chemical agent that interferes with the physiological action of another.

Nervous system

the network of nerve cells and fibers that transmits nerve impulses between parts of the body.

Central nervous system (CNS)

consists of the brain and spinal cord

Peripheral nervous system (PNS)

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

Nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs

Sensory neurons (afferent neurons)

A neuron that picks up impulses from sensory receptors and transmits them toward the central nervous system

Motor neurons (efferent neurons)

transmit motor information from the brain and spinal cord to muscles and glands

Interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

Somatic nervous system

A subdivision of the peripheral nervous system. Enables voluntary actions to be undertaken due to its control of skeletal muscles

Autonomic nervous system (ANS)

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

Sympathetic nervous system

the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations, Known as fight or flight.

Parasympathetic nervous system

rest and digest; the division of the autonomic nervous system that calms the body, conserving its energy

Reflex

a simple, automatic response to a sensory stimulus, such as the knee-jerk response

Endocrine system

Glands secrete hormones that regulate processes such as growth, reproduction, and nutrient use (metabolism) by body cells.

Hormones

Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

Adrenal glands

glands that help the body recover from stress and respond to emergencies

Michael Gazzaniga

1939-present; Field: cognition (neuroscience); Studied of the neural basis of mind with primary responsibility for initiating human split-brain research. In his subsequent work he has made important advances in our understanding of functional lateralization in the brain and how the cerebral hemispheres communicate with one another.

Charles Darwin

English natural scientist who formulated a theory of evolution by natural selection (1809-1882)

Gustav Fechner

1801-1887; Field: perception; Contributions: stated that the magnitude of a sensory experience is proportionate to the # of JND's that the stimulus causing the experiences above the absolute threshold

Ernst Weber

1795-1878; Field: perception; Contributions: just-noticeable-difference (JND) that eventually becomes Weber's law; Studies: 1st study on JND, developed Weber's law regarding the constant percentage of the difference threshold

David Hubel

Canadian neurophysiologist whose research on feature detectors helped demonstrate the presence of specialized neurons in the occipital lobe's visual cortex that have the ability to respond to specific features of an image.