Neuroanatomy Part IV Anatomy of the Brain continued

C. Cranial Nerves continued

Cranial Nerve Functions I -- smell II -- vision III -- extrinsic eye muscles and pupil reflexes IV -- superior oblique eye muscle V -- muscles of mastication, sensory for head, neck VI -- lateral rectus muscle VII -- facial muscles and most head glands, taste 2/3 VIII -- hearing and balance IX -- parotid gland, stylopharyngeus, taste 1/3 X -- muscles of pharynx, larynx, and parasympathetic XI -- trapezius and sternocleidomastoid, and others XII -- most intrinsic and extrinsic tongue muscles

Clinical: Cranial Nerve Lesions II Optic Nerve Lesions

Cranial Nerve Lesions • III, IV, and VI -- lesions will affect ability to turn eye in different directions • V-- UMN--increases jaw jerk reflex --LMN--weakness and atrophy of chewing muscles • VII -- sagging or paralyzed face

• VIII -- ipsilateral hearing loss and disturbances in equilibrium • X -- a great variety of problems. “hypernasality”, swallowing problems • XI --unable to turn head away from side of lesion • XII --unilateral lesion--loss of tongue movement on side of lesion

D. The Diencephalon 1. Thalamus 2. Hypothalamus epithalamus subthalamus

1. Thalamus

The Thalamus from all directions

2. Hypothalamus (dark blue)

E. Basal Ganglia 1. Corpus Striatum 1. Caudate Nucleus and Putamen 2. Lentiform or Lenticular Nucleus a) Globus pallidus (pallidum) b) Putamen 2. Internal Capsule Functions Regulation of movement, coordinating muscle groups for posture, and walking. Suppression of competing movements and decreasing muscle tone Cognitive and personality functions

Basal Ganglia

F. Limbic System 1. Major Components a. Cingulate gyrus c. Uncus e. Hippocampus Bodies b. Amygdala d. Fornix f. Mammillary 2. Functions a. Motivation b. Emotional drive (anger) c. Instinctual reflexes like feeding, mating, anziety, fear d. Learning and memory

Structures of Limbic System • from Zemlin, p. 334

G. White Matter of Cerebrum 1. Projection fibers Corona radiata Internal capsule - 2. Association fibers Ucinate Fasciculus Cingulum 3. Commissural Fibers Corpus Callosum Anterior Commissure

Corona Radiata

Association Fibers • Zemlin, p. 334

Corpus Callosum