1. Review
Dr. Anna L. Kiss
Department of Human Morphology and Developmental Biology
Semmelweis University, Budapest
2014

2. Eye 1.) Fibrous layer: sclera cornea 2.) Vasculose layer: choroid
ciliary body
iris
3.) Nervous layer: retina
optic retina (10 layers)
blind retina (2 layers)

3. Eye

4. Muscles of the eyeball Innervation: Oculomotory: sup.rectus
inf. rectus
medial rectus
inf. Oblique
Trochlear n: sup. oblique
Abducens n: lateral rectus

5. Inner muscles of the eye: Iris
Innervation: sympathetic and parasympathetic

6. Ear
1.) External ear
2.) Middle ear (tympanic cavity)
3.) Inner ear

7. Ear

9. Organ of Corti

10. Organ of Corti

11. Organ of balance

12. Organ of balance

13. Taste sensation: taste buds

14. Brainstem
Olive
Pyramid
Dorsal view
Ventral view

15. Functions of Reticular formation (RF)
Perception of pain (formation,modification)
Modify the reflex activity of spinal cord and brainstem)
Modification of activity of limbic system (emotion, sexual behaviour)
sleep-awarness balance
ARAS (ascending reticular activating system)

16. Functions of Reticular formation (RF)
Perception of pain (formation,modification)
Modify the reflex activity of spinal cord and brainstem)
Modification of activity of limbic system (emotion, sexual behaviour)
sleep-awarness balance
ARAS (ascending reticular activating system)

17. Afferent connections of cerebellum
Spinocerebellar tracts
Vestibulocerebellar tract
Pontocrebellar tract mossy fibres
Reticulocerebellar tract
Olivocrebellar tract- climbing fibres

18. Efferent connections of cerebellum
Cerebellovestibular tract
Cerebelloreticular tract
Cerebellorubral tract
Cerebellothalamic tract

19. THALAMUS
Each half of the brain contains a thalamus, a large, ovoid, gray mass of nuclei

20. Functional Divisions of the Thalamus
Thalamus is thought to be the crucial structure for the perception of some types of sensation, especially pain, and the sensory cortex may give finer detail to the sensation.
The thalamus can be divided into five functional nuclear groups:
Sensory nuclei are involved in relaying and modifying sensory signals from the body, face, retina, cochlea, and taste receptors
Motor nuclei convey motor information from the cerebellum to the precentral motor cortex,
Limbic nuclei, convey information from the hypothalamus and the cerebral cortex.
Multimodal nuclei, have connections with the association areas in the parietal lobe
Intralaminar nuclei– non specific connections (not well understood)
Interaction with cortical motor areas, the caudate nucleus, the putamen, and the cerebellum has been demonstrated.

21. Regulatory functions of the hypothalamus:
Functions — its most important job is to maintain homeostasis (or maintaining the body’s status quo); it does so by regulating three interrelated functions:
Neuroendocrine Function — controls hormone release by the pituitary gland.
Autonomic Function — integrates autonomic functions via direct projections to preganglionic autonomic neurons located in the brain-stem and spinal cord.
Emotions and Drives — it has numerous interconnections with the limbic system by which it generates behaviors involved in rage, aggression, escape, etc.

22. Basal ganglia caudate nucleus lentiforme nucleus claustrum
substantia nigra
putamen
globus pallidus

23. Basic definitions General sensation: Special sensation: Pain
Temperature
Pressure, vibration
Proprioception (information from joints, tendons, muscles)
Special sensation:
Taste

24. General organisation of spinal cord
Pseudounipolar cell

25. Division of sensory information
Epicritic sensation:
fine touch, fine vibration-pressure, proprioception, two point discrimination
B) Protophatic sensation:
crude touch, crude vibration-pressure
pain and temperature

26. Sensory pathways Epicritic sensory pathways
Cuneate and gracile fasciculi:
From the level of medulla the fibers cross the midline and named as medial lemniscus CONSCIOUS epicritic
Dorsal(posterior) spinocerebellar tract (uncrossed)
Ventral (anterior) spinocerebellar tract (crossed-at the level of spinal cord)
Terminate in the cerebellar cortex as mossy fibers
Both carry information about epicritic sensation but they do not reach the thalamusUNCONSIOUS tracts

27. Sensory pathways: protophatic pathway (anterolateral system)
Ventral and lateral spinothalamic tracts (crossed)
Ventral spinothalamic tract carries information about rough touch, vibration, pressure
Lateral spinothalamic tract carries information about pain and temperature
Both terminate in the thalamus VPl nucleus (conscius tract) and the fibers after synapse reach the primary somatosensibility area (Brodman 3,1,2 area)
Anterolateral system

28. Summary of sensory pathways
Epicritic, protopathic info
via trigeminal lemniscus
Head and neck
Thalamus Vpm
Taste info via solitary tract
Sensory cortex
Epicritic info via medial lemniscus
Spinal cord
(trunk and limbs)
Thalamus Vpl
Protopathic info via spinothalamic tract

29. Motor pathways I. Pyramidal tract =corticospinal tract
Anterior corticospianltract (crosses at the level of SC)
Lateral corticospinal tract (crosses at the level of medulla=pyramidal decussation)
The motor axis of the body
Gives the command to the skeletal muscles ‘what to do’

30. Innervation of skeletal muscles
Alpha motor neurons innervate the skeletal muscles of trunk and limbs (neuromuscular junctions-motor end plates)

31. Motor pathways II. Extrapyramidal system
Refine the activity of corticospinanl tract and gives the command ‘how to do’
Maintain a continous muscle tone (mainly inantigravitation muscles=extensors)
Synchronize the movements of eyeball and head-neck muscles
Reset the sensitivity of muscle spindle!!