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Phineas gage

This photo shows Phineas Gage holding the metal spike that impaled his prefrontal cortex. The image on the right shows a drawing of the skull with the metal spike inserted like it would have been when he was injured.
The victim of an accident while working on a railroad in 1848, Phineas Gage had a large iron rod impaled through the prefrontal cortex of his frontal lobe. After the accident, his personality appeared to change, but he eventually learned to cope with the trauma and lived as a coach driver even after such a traumatic event. (credit b: John M. Harlow, MD)

Secondary motor cortices

In generating motor responses, the executive functions of the prefrontal cortex will need to initiate actual movements. One way to define the prefrontal area is any region of the frontal lobe that does not elicit movement when electrically stimulated. These are primarily in the anterior part of the frontal lobe. The regions of the frontal lobe that remain are the regions of the cortex that produce movement. The prefrontal areas project into the secondary motor cortices, which include the premotor cortex    and the supplemental motor area    .

Two important regions that assist in planning and coordinating movements are located adjacent to the primary motor cortex. The premotor cortex is more lateral, whereas the supplemental motor area is more medial and superior. The premotor area aids in controlling movements of the core muscles to maintain posture during movement, whereas the supplemental motor area is hypothesized to be responsible for planning and coordinating movement. The supplemental motor area also manages sequential movements that are based on prior experience (that is, learned movements). Neurons in these areas are most active leading up to the initiation of movement. For example, these areas might prepare the body for the movements necessary to drive a car in anticipation of a traffic light changing.

Adjacent to these two regions are two specialized motor planning centers. The frontal eye fields    are responsible for moving the eyes in response to visual stimuli. There are direct connections between the frontal eye fields and the superior colliculus. Also, anterior to the premotor cortex and primary motor cortex is Broca’s area    . This area is responsible for controlling movements of the structures of speech production. The area is named after a French surgeon and anatomist who studied patients who could not produce speech. They did not have impairments to understanding speech, only to producing speech sounds, suggesting a damaged or underdeveloped Broca’s area.

Primary motor cortex

The primary motor cortex is located in the precentral gyrus of the frontal lobe. A neurosurgeon, Walter Penfield, described much of the basic understanding of the primary motor cortex by electrically stimulating the surface of the cerebrum. Penfield would probe the surface of the cortex while the patient was only under local anesthesia so that he could observe responses to the stimulation. This led to the belief that the precentral gyrus directly stimulated muscle movement. We now know that the primary motor cortex receives input from several areas that aid in planning movement, and its principle output stimulates spinal cord neurons to stimulate skeletal muscle contraction.

Questions & Answers

Describe the sequence of injuries that may occur if the extended, weight-bearing knee receives a very strong blow to the lateral side of the knee.
Dondon Reply
what is anotomy and waht is phesiology
chanbasha Reply
anatomy is classified the origin physiology is functional of origin
oHo
classified origin functional of origin
Sheryl
Anatomy is the origin of the human body Physiology is the function of the human body
Rose
Differentiate between pharmacist and apothecary
adanoor Reply
What is metatarsal
Ndotenyin Reply
bone of the foot is known as metatarsal
Patrick
yes 👆 right
Sneha
metatarsal (foot bone).....👍
Rishi
what is the meaning for cadavers
Malar
yes metatarsal are foot bone
Rakiya
the term "mental" pertain to which of the following a. chin b.navel c. ear d. nose e. skull
cris Reply
a
Lina
chin
Sneha
hi
Mohamed
skull
Monica
skull
Peter
chin
Kelly
skull
Juma
skull
Gul
skull
Laraib
skull
anwaar
skull
Nirmala
skull
Tessmol
chin
Derrick
mental chin nerve
Katarzyna
e. skull
Jennifer
skull
prince
e. skull
Natasha
It's not skull but chin
mwango
the skull
Rakiya
what are the three many components of the lymphatic system?
Milica Reply
those are...... organ, tissue and blood capillary or vessals
Juma
anatomical terms and use them appropriatly in the language of anatomy of anterior body landmarks
Teody Reply
what is human anatomy?
rascal Reply
lts stady structured human body's
Sa
what is the study of how the body functions?
Bright
What is human anatomy
Sherifat
human antomy is the body of structure
Malar
is the study of human body
Rakiya
what is abdomipelvic cavity?
david Reply
Includes all organs within the abdomen(stomach,intestines) and those from the pelvic region hence the name... abdomipelvic
Maureen
where can we find the short bones
Chidi Reply
Carpal bones are examples of short bones
Dara
what is blood supply
Chidi
on upper limb and lower limb
Juma
carpal bones
Priya
during pregnancy which would more increase size the mothers abdominal or pelvic cavity?
Nurmalyn Reply
pelvic cavity I think
Priya
What is anatomical position
Nwoye
pelvic
Maureen
@ Nwoye... when standing erect, feet parallel, arms hanging at the sides with palms facing forward
Maureen
The pelvic cavity
Rakiya
pelvic
Malar
define the main directional terms of the body
cris Reply
during physical exercise respiratory rate increace two student are discussing the mechanisms involved. student A claim they are positive feedback and student B claim negative feedback do you agree with student A or B and why
cris
what is the physiology of circulation
Chidi
please I mean the physiology of criculation
Chidi
blood flow refers to the movement of blood through the vessels from arteries to the capillaries and then to the veins
Laraib
the heart&the lungs
Rakiya
during pregnancy, which would more size the mother's abdominal or pelvic cavity? explain
cris Reply
list and define the three plane of devision of the body
cris
complete the following statements using correct directional terms for human being. 1. the navel is________to the nose 2. the heart is______to the breastbone(sternum) 3 the ankle is______to the knee 4 the ear is______to the eyes.
cris
1. superior 2. posterior 3. superior 4. lateral
Mnm
anterior fuerior
Chidi
inferior medial posterior lateral we
Susan
name the system of the body and its function
cris Reply
11 system are human body 1.integumentary system 2. skeletal system 3. muscular system 4. nervous system 5. endocrine system 6. cardiovascular system 7. lymphatic system 8. respiratory system 9. digestive system 10. urinary system 11. reproductive system male and female.
Vineeta
during pregnancy, which would more size the mother's abdominal or pelvic cavity? explain
cris
how the body maintain hormeostasis in terms of bloodglucose level
cris Reply
It releases hormones from the pancreas insulin and glucagon
TONY

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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