Physiology 2130 Lecture Notes - Lecture 25: Entorhinal Cortex, Rabies Virus, Uterotonic
1 May 2018
School
Department
Course
Professor
Lecture 027: Hypothalamus and the limbic system
Limbic System
● On the border (limbo) with the brainstem
● Is the phylogenetically old cortex (primitive, reptilian cortex)
● Composed of the cingulate cortex, hypothalamus, amygdala, hippocampus
Limbic System Function
● Emotion
● Motivation state (generates behaviours)
○ Cold/hot (put on clothes, moving)
○ Hunger (feeding)
○ Thirst (drinking)
○ Rage/fear (attack/defense)
■ Rabies virus affects the limbic cortex: generates bouts of terror/anger
■ Reactions in daily life: road rage, aggressive response to a sudden slap
○ Sexual urge (mating)
○ Pain (avoidance)
■ Somatosensory cortex: location, intensity and timing of pain
■ Cingulate cortex: emotional component (psychological “bad” aspect)
● Lesion in this area will cause a patient to feel the pain but is
unbothered by it
● Behaviours
● However, these instinctive reactions generated by the limbic cortex, can be overcome by
the neocortex
Hypothalamus (“hypo” - under the thalamus)
● Less than 1% of the volume of the brain
● Remarkable number of function
● Lesion in this region can be catastrophic
● Connects and is a part of the the limbic system/cortex
● Retina
○ Important input to the hypothalamus
○ For circadian rhythm
● Outputs
○ Posterior pituitary
■ Release oxytocic and antidiuretic hormone (ADHs)
● Portal system
○ Sends release and release inhibiting hormones from the hypothalamus to the
anterior pituitary via the hypophyseal portal veins
■ LH, FSH, ACTH, etc
● Have connections to the medulla and spinal cord
● Have special neurons
○ Contains receptors for osmol, glucose levels, temperature, Na+, fat/leptin
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
On the border (limbo) with the brainstem. Composed of the cingulate cortex, hypothalamus, amygdala, hippocampus. Is the phylogenetically old cortex (primitive, reptilian cortex) Rabies virus affects the limbic cortex: generates bouts of terror/anger. Reactions in daily life: road rage, aggressive response to a sudden slap. Somatosensory cortex: location, intensity and timing of pain. Cingulate cortex: emotional component (psychological bad aspect) Lesion in this area will cause a patient to feel the pain but is. However, these instinctive reactions generated by the limbic cortex, can be overcome by unbothered by it the neocortex. Less than 1% of the volume of the brain. Lesion in this region can be catastrophic. Connects and is a part of the the limbic system/cortex. Sends release and release inhibiting hormones from the hypothalamus to the anterior pituitary via the hypophyseal portal veins. Have connections to the medulla and spinal cord. Contains receptors for osmol, glucose levels, temperature, na+, fat/leptin.
