Transcript Neuroscience and the Brain

Neuroscience
and the Brain
Cerebral Cortex and
Hemispheres
 Cerebral cortex:
outermost layer of the
brain
 Spread out all the
wrinkles-cerebral cortex
is the size of a bath
towel!
 Fissure marks the
separation between
hemispheres
 Corpus callosum
connects the
hemispheres
Lobes
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Frontal lobe
Motor strip
Sensory strip
Parietal lobe
Occipital lobe
Temporal lobe
Frontal Lobe
 Complex!
Prefrontal lobe: allows us to “mentally
travel in time,” to remember past events
and “see” ourselves in past situations
Frontal lobe: allows us to come up with
strategies or plans of action and makes
sense of our environments
Likely also responsible for social control
and following social rules—case of
Phineas Gage
Motor and Sensory Strips
 Motor strip: controls all movement; contained
in frontal lobe
 If you activate parts of the motor strip during
neural surgery, different parts of the body will
react and move
 Sensory strip: controls all feeling; contained in
parietal lobe
 If you activate parts of the sensory strip in
surgery, the patient would feel itches, tingles,
and even pain in parts of the body (most
neurosurgery patients are awake during
surgery!)
Occipital Lobe
 Responsible for
VISION
 Even when your
eyes are closed, all
images in your
thoughts and dreams
activate your
occipital lobe
Temporal Lobe
 Responsible for
HEARING and
SPEECH
 Some centers for
speech are located
here, though they
overlap
 Most speech areas
are only in left
hemisphere
Hemispheres and
Handedness
 One hemisphere has dominance—you
can tell by what hand you write with!
Famous Lefties
Hemispheres
 Left: verbal or speech material, language,
logic, writing
 Right: objects in space, art, music, some
mathematical reasoning, emotional material
Lower Level Brain
Structures
 Brainstem: “basement” of the
brain, begins where spinal cord
swells and meets the brain,
forming the Medulla
 Pons: assists in controlling
autonomic functions, sleep,
arousal
 Reticular formation: fingershaped network of neurons that
extends from spinal cord to the
thalamus
 Reads and directs nerve impulses
between brain and body
 Controls alertness
Lower Level Brain
Structures
 Thalamus: all senses
except smell are routed
through thalamus; also
receives the brain’s
replies and then directs
them to the cerebellum
and medulla
 Cerebellum: “little brain”
 Coordinates voluntary
movement
Limbic System
 Hippocampus: essential to memory
processing
 Amygdala: aggression and fear
 Hypothalamus: regulates hunger and
thirst, body temperature, sexual behavior
 Smell is routed through limbic system,
hence its connection to memory
Nervous System
 Somatic: controls movements of skeletal
muscles
 Autonomic: controls glands of muscles of
internal organs, including heartbeat, digestion,
and glands
 Sympathetic: prepares us for defensive action
 Parasympathetic: counters the sympathetic
nervous system; keeps us in a steady internal
state
Endocrine System
 Linked to neurons through
neurotransmitters