lecture recording on 18 March 2025 at 15.16.42 PM

Overview of Retina and Visual System

• Ophthalmoscope Tool: Examines retina, blood vessels, and optic disc (the blind spot).

• Blood Vessels: Consist of red arteries and blue veins.

• Macula and Fovea Centralis: Region high in cones for color vision.

Photoreceptors

• Cones: Responsible for color vision, divided into red, green, blue types.

• Rods: Enable dim light/ peripheral vision, not for color detection.

Color Blindness

• Types: Partial (one cone type missing) and Full (all cones nonfunctional).

• Demographics: More common in males.

Visual Processing

• Right visual field processed in the left occipital lobe and vice versa.

• Visual Acuity Tests: Use of the Snellen Chart (e.g., 20/20 vision).

Astigmatism

• Definition: Focus issues due to lens/cornea shape.

• Testing: Assessing line evenness with the Dial Test.

Inner Ear Structure and Function

• Components: Outer Ear (auricle), Middle Ear (tympanic membrane, ossicles), Inner Ear (cochlea, vestibule).

• Auditory Nerve: Connects sound vibrations to brain.

Hearing Tests and Disorders

• Audiometric tests assess hearing loss (sensorineural, etc.).

• Treatments include hearing aids and cochlear implants.

Olfactory System

• Odor Detection: Chemical receptors processed in the brain.

• Cribriform Plate: Bone aiding in olfactory signal transmission.

Taste Perception

• Taste Buds: Located on the tongue; types respond to different tastes.

• Cranial Nerves: Involved in taste signal transmission.

Spiciness Sensation

• Understanding: Spiciness from pain receptors (nociceptors).

• Scoville Scale: Measures spiciness of peppers (e.g., Carolina Reaper).

Exam Preparation

• Final exam on Tuesday; focus on labeling structures of the retina, ear, and olfactory systems.