Biology

phrenology

the importance of testing theories scientifically. it was derived from the theories of the idiosyncratic Viennese physician Franz Joseph Gall (1758-1828)

Franz Joseph Gall's principles

- the brain is the organ of the mind

- the mind is composed of multiple distinct innate faculties

- because they are distinct

each faculty must have a separate seat or "organ" in the brain

- the size of an organ

other things being equal

- the shape of the brain is determined by the development of the various organs

- as the skull takes its shape from the brain

the surface of the skull can be read as an accurate index of psychologist aptitudes and tendencies

neurons

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

Parts of a neuron

cell body

cell body

Largest part of a typical neuron; contains the nucleus and is the cell's life support center

dendrites

a neuron's bushy

axon

attached to the soma

myelin sheath

A layer of fatty tissue segmentally encasing the fibers of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

terminal branches

The branched end of the axon that contains neurotransmitters.

glial cells (glia)

cells in the nervous system that support

"All or none" response

when more stimulation does not produce a more intense neural transmission. the neuron's reaction is an all-or-none response when the firing happens at full response or not at all

excitatory signal impulses

triggering action

inhibitory signal impulses

depressing action

polarization

the resting state of the neuron where the charge is more positive outside the membrane and more negative inside

Depolarization

the action potential

Repolarization

the refractory period; the closing of the membrane and reestablishing a more negative charge inside the cell

Neurotransmitters

Chemicals that transmit information from one neuron to another

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron (small gaps are called the synaptic cleft or gap)

reputake

a neurotransmitter's reabsorption of excess neurotransmitters

dopamine

A neurotransmitter associated with movement

serotonin

A neurotransmitter that affects hunger

Acetylcholine

A neurotransmitter that enables learning and memory and also triggers muscle contraction

Norepinephrine

A neurotransmitter involved in arousal

Gamma-aminobutyric acid (GABA)

a major inhibitory neurotransmitter

Glutamate

A major excitatory neurotransmitter; involved in memory

Endorphins

Neurotransmitters that influence the perception of pain or pleasure

Agonist

a drug molecule that increases a neurotransmitter's action

antagonist

a drug molecule that inhibits or blocks a neurotransmitter's action

direct vs. indirect effects

These neuro-acting drugs can be further broken down based on whether they have a direct or indirect effect. Those that have a direct effect work by mimicking the neurotransmitters because they are very similar in chemical structure. Those that have an indirect impact work by acting on the synaptic receptors.

agonsits vs. antagonists

Some drugs are known as agonists and function by increasing the effects of specific neurotransmitters. Other drugs are referred to as antagonists and act to block the effects of neurotransmission.

Nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles

brain

The mass of nerve tissue that is the main control center of the nervous system

spinal chord

2 way connections between the Peripheral Nervous System (PNS) and the brain

The three types of neurons are:

sensory

sensory neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord (CNS)

motor neurons

neurons that carry outgoing information from the brain and spinal cord(CNS) to the muscles and glands

interneurons

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

Central Nervous System (CNS)

consists of the brain and spinal cord and is the decision maker which is responsible for coordinating incoming sensory messages and outgoing outdoor messages

Peripheral Nervous System (PNS)

the sensory and motor neurons that connect the CNS to the rest of the body (also contains the somatic and autonomic nervous system)

Somatic Nervous System (SNS)

the part of the peripheral nervous system that controls voluntary movement of skeletal muscles (concerns sensory input and motor output)

autonomic nervous system (ANS)

a set of nerves that carries involuntary and automatic commands that control blood vessels

Sympathetic Nervous System (SNS)

the division of the autonomic nervous system that arouses the body

parasympathetic nervous system (PNS)

Division of the autonomic nervous system that slows down body functions

Andrenal glands

the "fight or flight" process that produces hormone that speeds up your body process

pituitary glands

The endocrine system's most influential gland. Under the influence of the hypothalamus

lesion

brain tissue that is destroyed and studied by researchers

stimulation

brain regions are stimulated electrically

Brain scans that indicate brain functioning are:

EEG

EEG scans

a recording of the waves of electrical activity across the brain's surface measured by electrodes placed on the scalp

MEG scan (magnetoencephalography)

a brain imaging technique that measures magnetic fields from the brain's natural electrical activity

CT (CAT) scan (computed tomography scanning)

a series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body

Brain scans that show the structures of the brain are:

PET

PET scan (positron emission tomography)

a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

MRI scan (magnetic resonance imaging)

uses radio waves and a very strong magnetic field to produce images of the soft tissue

fMRI scan (functional magnetic resonance imaging)

reveals blood flow and brain activity by comparing successive MRI scans (shows the function)

Structures of the brain stem are:

medulla

medulla

the base of the brainstem; controls heartbeat and breathing

pon

above the medulla

reticular formation

a nerve network that travels through the brainstem and thalamus and plays an important role in controlling arousal

thalamus

the brain's sensory control center

cerebellum

the "little brain" at the rear of the brainstem; functions include processing sensory input and coordinating movement output and balance

Limbic system

neural system (including the hippocampus

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating

amygdala

two lima bean-sized neural clusters in the limbic system; linked to emotion.

Hippocampus

A neural center with "arms" that wrap around the thalamus that helps process explicit memories for storage.

cerebral cortex meaning:

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.

parts of the cerebral cortex

frontal lobe

frontal lobe

associated with reasoning

parietal lobe

receives sensory input for touch and body position

temporal lobe

each lobe receives auditory information

occipital lobe

A region of the cerebral cortex where each lobe processes visual information

motor cortex

controls voluntary movements

somatosensory cortex

an area at the front of the parietal lobes that registers and processes body touch and movement sensations

auditory cortex

receives information from the ears

visual cortex

receives information from the eyes

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather

Broca's area

Controls language expression - an area of the frontal lobe

Wernicke's area

controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe

Plasticity

the brain's ability to change

neurogenesis

the development of new neurons

split brain

a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

How are the eyes wired to the brain?

In each eye

visual field

the whole area that you can see without moving your head or eyes

intact brain

data is readily transferred acros the corpus callosum from both hemispheres of the brain

left hemisphere

contains Broca's area and Wernicke's area (involved in expressive and receptive language)

right hemisphere

controls the left side of the body; creative

dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks (the two-track mind)

blindsight

a condition in which a person can respond to a visual stimulus without consciously experiencing it

parallel processing

the processing of many aspects of a problem simultaneously which helps to take care of routine business (faster than sequential)

sequential processing

the processing of one aspect of a problem at a time which helps to provide focus for solving newer problems (slower than parallel)

heredity (nature)

the transmission of traits from one generation to the next

environment (nurture)

every non-genetic influence

What do behavior geneticists study?

relative power and limits of genetic and environmental influences on behavior

what is a chromosome and how many does a person have?

they are threadlike structures made of DNA molecules that contain genes. each person has 46 chromosomes; 23 you inherit from mom and 23 from dad