62 terms

The Human Brain: Lab Exercise 11

elevated ridges of cerebral tissue
shallow grooves separating gyri
Central Sulcus
the sulcus separating the frontal and parietal lobes
Lateral Sulcus
the sulcus separating the frontal and temporal lobes. the insula lies medial to the lateral sulcus
Longitudinal fissure
deep groove separating the cerebral hemispheres
Transverse fissure
deep groove separating the cerebral hemispheres from the cerebellum
Five different Lobes
frontal, parietal, temporal, occipital, insula
areas of the cerebral hemispheres separated by fissures or relatively deep sulci that are consistent among individuals; usually named for the cranial bones that lie over them
Cerebral Cortex
composed of gray matter; location of our conscious mind; can be subdivided into functional areas
Primary motor cortex
controls most voluntary motor functions
Premotor cortex
controls learned motor skills that are repetitious or have a pattern
Speech center (Broca's area)
controls muscles involved in speech production
Primary somatosensory cortex
identifies regions of the body being stimulated; receives information from sensory receptors located in the skin and from proprioceptors in skeletal muscles
Somatosensory association cortex
integrates information received from the primary somatosensory cortex and enable perception/identification of stimuli
Visual area
receives visual stimuli that originates on the retinas of the eyes (primary visual cortex) and interprets the visual stimuli (visual association area)
Auditory area
receives auditory stimuli that originates from the inner ear (primary auditory cortex) and interprets the auditory stimuli (auditory association area)
Olfactory cortex
receives and interprets olfactory (smell) stimuli
Prefrontal cortex (Anterior association area)
involved with out intellect, complex learning ability, recall, and personality; necessary for production of abstract ideas, judgement, reasoning, persistence, long-term planning, concern for others, and conscience
General interpretation area (Posterior association area)
area receiving input from all sensory association areas and integrating the incoming signals into a single thought or understanding of a situation
Cerebral White Matter
consists primarily of myelinated fibers bundled into tracts; responsible for communication between cerebral areas and between the cerebral cortex and lower CNS centers
Commissural fibers
form tracts (commissures) connecting corresponding gray areas of two hemispheres
Corpus callosum
largest commissure
Association fibers
form tracts connecting different parts of the same hemisphere
Projection fibers
form tracts that connect the cerebral hemispheres to the lower brain and spinal cord
Basal nuclei
island of gray matter located deep within the white matter of the cerebral hemispheres; play a role in the subconscious regulation of muscle movement
gateway to the cerebral cortex
Three activities of the Thalamus
1. Sorting-out, editing, and routing sensory impulses to appropriate region of sensory cortex
2. Transmitting emotional and visceral information between the cerebral cortex and hypothalamus
3. Transmitting impulses from the cerebellum and basal nuclei that help direct the activity of the motor cortices
autonomic control center of the body
Seven activities of the Hypothalamus
1. coordination fo voluntary and autonomic activities
2. regulation of emotional response
3. regulation of endocrine functioning
4. regulation of water balance and thirst
5. regulation of food intake
6. regulation of sleep-wake cycle
7. regulation of body temperature
Pituitary gland
not actually part of the hypothalamus but is directly controlled by it; is part of the endocrine system that releases hormones; sits in the sella turcica of the sphenoid bone
stalk of hypothalamic tissue that connects the pituitary gland to the hypothalamus
Mammillary bodies
relay station in the olfactory pathways, contains motor nuclei that control motor reflexes associated with eating
Epithalamus: Pineal gland
secretes the hormone melatonin; helps regulate sleep-wake cycle, mood, and reproductive functions
Choroid plexus
produces cerebrospinal fluid
processes information from cerebral motor cortex, proprioceptors, and visual and equilibrium pathways; provides instructions to cerebral motor cortex and subcortical motor centers that result in proper balance and posture and smooth, coordinated skeletal muscle movements
Arbor vitae
white matter of the cerebellum named for its tree-like appearance (literally means "tree of life"); connects cerebellar cortex with cerebellar peduncles
Cerebellar peduncles
contain tracts connecting the brain stem to the cerebellum
Brain stem
produces rigidly programmed, automatic behaviors; pathway between higher and lower neural tracts; associated with 10 of the 12 pairs of cranial nerves
Mesencephalon (Midbrain)
plays a role in pain suppression, visual tracking of moving objects, startle response to unexpected sounds, subconscious control of muscle tone and body position, maintaining consciousness; contains nuclei for cranial nerves III and IV
Corpora quadrigemina
largest nucleus in the white matter of the midbrain; composed of the superior and inferior colliculi
Superior colliculi
visual reflex centers that coordinate head and eye movement
Inferior colliculi
auditory reflex center that plays a role in reflexive responses to sound
Cerebral peduncles
contains motor tracts that connect the cerebral cortex to the spinal cord and connect the cerebral cortex to the cerebellum via the pons
Substantia nigra
responsible for releasing the neurotransmitter, dopamine; functionally, it is part of the basal nuclei
relays sensory and motor information to the cerebellum, helps regulate information; provides tracts for communication between higher brain centers and the medulla oblongata; contains nuclei for cranial nerves V through VIII
Medulla oblongata
plays a role in regulating heart rate, blood vessel diameter, and respiratory rate; provides tracts for all communication between brain and spinal cord; contains nuclei of cranial nerves VIII through XII
Decussation of the pyramids
location where nerve fibers cross over to the opposite side of the body; reason (in part) why the left side of the brain controls right side of body and right side of brain controls left side of body
Vestibular Nuclear Complex
nucleus responsible for equilibrium and balance; receives stimuli from the middle ear
Limbic system
includes portions of the medial cerebrum and diencephalon
functions of the limbic system
1. control of emotions
2. linking the conscious thought of the cerebral cortex with the emotions and autonomic nervous system
3. facilitating memory processing
Reticular formation
loosely clustered neurons forming three columns along the length of the brain stem; has direct axonal connections with nearly every other part of the brain
functions of the reticular formation
1. control of autonomic functions such as respiratory and cardiovascular activity
2. control of autonomic or reflexive motor activity such as some eye movements
3. keeping brain alert and filtering out repetitive, familiar, or weak signals in our environment
layer of bone encasing the brain and spinal cord; the skull encases the brain while the vertebral column encases the spinal cord
connective tissue membranes that lie just external to the central nervous system organs
functions of meninges
1. cover and protect the CNS
2. protect blood vessels and enclose venous sinuses
3. contains cerebrospinal fluid
4. form partitions within the skull
Dura Mater
tough, leathery, outermost meninx surrounding the brain; is fused to the periosteum of the skull but not of the vertebrae
Arachnoid Mater
loose, middle meninx of epithelial tissue with web-like extensions that attach it to the underlying pia mater
Pia Mater
delicate connective tissue with rich supply of blood vessels; clings tightly to the brain
functions of the Cerebrospinal Fluid
1. gives brain buoyancy that helps support and cushion the brain
2. provides nutrients to the brain
3. carries chemical signals (e.g. hormones) to the brian
4. removes waste products from the brain
Blood-brain Barrier
a selective barrier that allows nutrients to cross by facilitated diffusion but keeps most metabolic waste, toxins, and drugs (except fat soluble substances) out; due to characteristics of the capillaries within the brain
three characteristics of the capillaries within the brain
1. continuous endothelium of capillary wall with tight junctions between endothelium cells
2. a thick basal lamina
3. the astrocytes holding the capillaries in place
Epidural Space
space between the vertebral column and dura matter filled with areolar and adapose loose connective tissue; provides additional support and protection to the spinal cord