The construction and function of the neurons and the brain and their influences on behavior
Nodes of Ranvier
There are 9-times more glial cells than neurons in the brain.They communicate with neurons and each other about the messages traveling among neurons. They can alter signals at the synapse and influence where synapses are formed. They may be critical in forming memories and repairing nerve damage and play a major role in diseases like Alzheimer’s and Parkinson’s.
Nervous System Chemicals & Their Effects
Type Function Effects Where Produced Examples
Neurotrans- Enable neurons to Diverse, depend- Brain, spinal cord, Serotonin,
mitters excite or inhibit ing on which peripheral nerves, Dopamine,
each other circuits are act- certain glands Norepinepherine
ivated or sup-
Endorphins Usually modulate Reduce pain, pro- Brain, spinal cord (Several varieties)
the effects of mote pleasure;
of neurotrans- also linked to
mitters learning, memory
& other functions
Hormones Affect function- Dozens, ranging Primarily in the Epinephrine, nor-
ing of target from promotion endocrine glands epinephrine,
organs & tissues of digestion to estrogens,
regulation of androgens
Fight – or - Flight
Health Functions, Growth & Well-Being, Homeostasis
Some (e.g. cocaine) stop reuptake, others take the place of specific neurotransmitters.
Organization of the
The Brain contains between
100 Billion & 1 Trillion Neurons
with more than 1000 Synapses
The Brain Processes
About 400 BILLION
Bits of Information
At A Time.
We're Aware of Only
About 2000 Bits.
The Analytic Hemisphere. Dominant in most people. Interprets
actions, moods, & thought
theories about actions &
feelings, & tries to bring
order & unity to our
conscious lives. It is
specialized for language
in 95% of right-handed &
75% of left-handed. Makes
causal inferences. Solves problems via established methods & well-ordered plans.
The Synthetic Hemisphere. Specialized in facial recognition. Has its own consciousness. Perceives
melodies, patterns, & analyzes
nonverbal patterns. Judges
grammatical correctness of a
sentence. It is holistic and
has limited language skills.
Has a larger volume of an
“association cortex” for
complex information pro-
cessing. It makes leaps of insight.Beginning at the Top
The left hemisphere controls the right side of the body and the right hemisphere controls the left side of the body.
What purpose does Contralateral Control serve?
The Medulla, the Pons, and the Cerebellum
The Thalamus, the Hypothalamus, and the Reticular Formation
Muscles, Bones, Skin,
Pain, & Internal Organs
The Cerebral Cortex
Encodes, Stores, & Recalls Sequences;
Processes Serial Order Information
Within the Context of a Motor Task;
Recognizes & Remembers Sequence of
Events in Time.
Word Production & Grammatical
Processing; Semantic Analysis;
Motor Patterns for Speech Production
Attention to Details; Visual & Auditory
Words; Discriminates Familiar & Un-
familiar Stimuli; STM for Abstract
Symbols; Sentence Memory; Visual
Orienting; Concentration; Shifting of
The Cerebral Cortex
is the outer "Gray Matter"
& the "Association Areas."
Working Memory; Word & Speech Perception
(Left); Visual & Auditory Words; Associates Words;
Analysis & Meanings of Items; Self-Analysis;
Object Identity; Recognizes Facial Features; Action Plans
Organizes Visual Information;
Activates &Processes Color, Shape,
&Motion; Creates Visual Images;
Maps & Analyzes Visual Information;
Processes Visual Words
Listening to Words; Working Memory;
Processes Words Visually & Auditorially;
Visual Computation & Motion; Primary
Auditory Cortex; Monitors Speech;
Generates Verbs; Speech Output
Understanding & Expression of
Language; Listening to Words;
Semantic Analysis & Interpretation
Has Open and Closed Gates.
Processes information very quickly.
Components of the computer are reliable but removing 1 or 2 can disrupt processing.
Each gate receives a single input and sends that input on.
Recognizes only precise input.
Operates sequentially and in parallel.
Has Open, Closed, and Almost Gates.
Processes information slowly.
Neurons are somewhat unreliable, but deletion of quite a few is not likely to make a major difference in behavior.
Neurons receive input from thousands of other neurons and connects to thousands of other neurons.
Recognizes patterns.The Brain/Computer Connection
Called “the glands of personality” in the early 20th century.
Posterior & Anterior
Functions: Reproduction & Sleep-Wake Cycles
Low Melatonin: Insomnia
High Melatonin: Decreased Motor Activity, Fatigue, & Lower Body Temperature
Posterior Lobe: Oxytocin, Vasopressin, & Antidiuretic Hormone
Anterior Lobe: Hormones Include Thyroid-stimulating Hormone, ACTH, FSH, & Prolactin
Affects growth and the other glands
Controls Calcium Levels
High Calcium Levels:
Lack of Concentration
Decreased Sex Drive
Regulates Energy Levels & Electrolite & Fluid Balance, Kidney & Sexual Function
Anxiety & Nervous Shaking
Controls Blood Sugar & Glucose Metabolism & Digestive Secretions
Secretions: Estrogen, Progestrone, & Androstenedione
Secretions: Testosterone & Other Androgens
Low Testosterone: Decreases Sex Drive
High Testosterone: Heightened Bisexuality