Exam #1- Brain and Behavior

Chapter 1, 2, 3 and 4

Neurons

Building blocks of the brain

Cell Membrane

Neurons are enclosed by a semipermeable membrane & filled with salty cytoplasm

Soma (Cell Body)

Metabolic Functions; Chromosomes (DNA strands) & Genes (Sections of chromosomes)

Ribosomes

Produce Proteins

Golgi Apparatus

Packages cellular materials into vesicles fro transport

Mitochondria

Generates energy from Glucose

Cytoskeleton

Microtubules & neurofilaments proved shape & structure of cell

Microtubules

Track along which packets of proteins travel by the action of motor proteins

Axoplasmic Transport

Proteins made in the soma —> transported to axon terminals

Dendrites

Receive information from other cells

Arborization

Degree of branching of dendrites reflects the complexity of the neurons information-processing function

Dendritic Spines

Dendrites covered with these; short that increase surface area

Axon

Transmit electrical signals form the axon hillock

Axon Terminal/Terminal Button

End of axon

Differences between the Cytoplasm of Axon Terminal & Axon

No microtubules in terminal, Presence of Synaptic Vesicles, Abundance of membrane proteins; large number of mitochondria

Synapses

Communication between 2 neuron occures

Three Components of Synapses

Presynaptic membrane

Postsynaptic membrane

Synaptic cleft

Myelination

Myelin & Nodes of Ranvier

Myelin

Fatty, protective, insulating layer around neurons/nerve cells (made up of glial cells —> Oligodendrocytes & Schwann cells)

Nodes of Ranvier

Gaps between section of Melin where the axon is exposed

Neurons classification by Shape

Multipolor

Bipolar

Unipolar

Neuron classification by Function

Motor

Sensory

Interneurons

Glial Cells

Support and enhance neuron functions

Astrocytes Shape

Star-Shaped

Astrocytes Functions

Blood brain barrier maintenance, control blood flow, engird/nutrient supply, synapse formation & pruning

Microglia

Clean up dead and dying neurons via phagocytosis; part of immune system; protect from bacteria, viruses and other organisms

Oligodendrocytes Cells

Provide myelin in the central; multiple segments

Schwann Cells

Peripheral system; 1 segment

Gaps between segments

Nodes of Ranvier

Ependymal Cells

Production and movement of cerebral spinal fluid

Glial Cell disorders/diseases

Glial cells respond to injury by edema (swelling) & susceptible to tumors

Astrocytes disorders/diseases

Influence brain chemistry and have been implicated in epilepsy

Microglia disorders/diseases

Implicated in degenerative disease including Alzheimers

Demyelinating Disease

Multiple Sclerosis (MS)

Neuroaxis & Anatomical Orientations

Rostral / Caudal

Anterior / Posterior

Medial / Lateral

Dorsal / Ventral

Superior / Inferior

Rostral / Anterior

Towards the nose/front

Caudal / Posterior

Towards the back of the brain

Medial

Center

Lateral

On sides of the brain

Dorsal / Superior

Towards the top

Ventral / Inferior

Towards the bottom

Orientations for viewing Brain & Body

Horizontal Plane

Sagittal Plane

Coronal Plane

Anatomical Orientations

Afferent / Efferent

Proximal / Distal

Laterality

Bilateral

Unilateral

Ipsilateral

Contralateral

Afferent

Arriving at the structure

Efferent

Exit at the structure

Proximal

Close by (talking to other neuron)

Distal

Far away (talking to other neuron)

Bilateral

Symmetrical; two hemispheres; both sides of the brain

Unilateral

One side of the brain

Lpsilateral

Left leg, left brain; same side

Contralateral

Left side of the brain; right side of the body

Right side of the brain; left side of the body

Horizontal

Birds Eye view (top of the brain)

Sagittal Plane

Side view (one side of the brain at the time)

Coronal Plane

Looking at the brain head on

Scientific Method

Process of objectively establishing facts through testing and experimentation

Steps for Scientific Method

Making observations

Defining / identifying problem

Forming a hypothesis

Conducting an experiment

Analyzing date

Reaching a conclusion

Replication

Repeating an experiment on different subjects / participants or making similar observations in different patients

Interpretation

Collected data into context of the field

Verification

Critiques from others (peer review)

Variable

Something that changes; types, categories, way to define

Data

Observation or measurements

Construct

A conceptual variable that is known to exist but cannot be directly observed

External Factor of a Construct

An observable behavior or event that is presumed to reflect the construct itself

Operational Defintion

Detailed specifications about how to measure the construct & variable

Independent Variable

Manipulated; Quasi-independent variables

Dependent Variable

Measured; Outcome / response

Levels of Independent Variable

Number of levels of an independent variable is the number of experimental conditions

Nominal Date

Categorizes data; non-numeric, no ranking or in order

Ordinal

Categorizes & ranks the data; ranking, likest scales, in order

Interval Data

Categorizes & ranks items but have no true zero; temperature

Ratio Data

Caterogies, ranks, order ideas and equal intervals and a true zero; length, height, weight

Division of the Nervous System: Central Nervous System (CNS)

The brain and spinal cord; encased in bone; Neurons (Nuclei, Tracts)

Division of the Nervous System: Peripheral Nervous System (PNS)

All parts of the nervous system found outside the skull and spinal column; NOT encased in bone; Nerves (Ganglia)

Motor Nerves (Part of PNS)

Transmit information from the CNS to muscles, organs and glands

Sensory Nerves (Part of PNS)

Convey information from the body to the CNS

Divions of PNS

Somatic Nervous System and Autonomic Nervous System

Somatic Nervous System

Connect brain and major muscles and sensory systems; Spinal nerves (31 pairs)

Autonomic Nervous System

Nerves that primarily control the viscera (internal organs) Sympathetic & parasympathetic divisions, spans the CNS & PNS

Spinal Nerves Segment of Spinal Cord

Cervical (Neck) - 8 segments

Thoracic (Trunk) - 12 segments

Lumbar (Lower Back) - 5 segments

Sacral (Pelvic) - 5 segments

Coccygeal (Bottom) - 1 segment

Spinal Nerves

Each spinal nerve consists of an ongoing bundle of motor nerves axons and incoming bundle of sensory nerve axons

Cranial Nerves

12 pairs of nerves mainly connect brain to head, face, neck & internal organs; Carry sensory information (toward the brain), motor commands (away from the brain), Both sensory and motor information

Olfactory

Optic

Oculomotor

Trochelear

Trigeminal

Abducens

Facial

Vestibulococoihelear

Glossopharyngeal

Vagus

Spinal Accessory

Hypoglossal

Three major divisions of the Autonomic Nervous System

Sympathetic Nervous System, Parasympathetic Nervous System and Enteric Nervous System

Enteric Nervous System

Local network of neurons that governs function of the gut (controlled by the CNS, key role in maintaining fluid & nutrient balance)

Autonomic Ganglia

Groups of neuron cell bodies located outside the CNS

Preganglonic Neuron

Axons extend from the CNS and synapse in the autonomic ganglia

Postganglionic Neuron

Axons extend from the autonomic ganglia to targets in the body

Sympathetic Nervous System

Flight or flight, prepares body for action