Special Senses Anatomy

Protect the eye from dust, debris, and other irritants.

Sebaceous glands that prevent eyelids from sticking together. Malfunction can cause dry eyes or stuck eyelids.

Lacrimal glands produce tears, which travel through ducts to the nasal cavity. This pathway ensures continuous tear delivery for lubrication, protection, and nutrient supply to the eye.

The rectus muscles move the eye up, down, left, and right. The oblique muscles allow circular movements.

The fibrous layer (outermost) provides structure and protection, the vascular layer (middle) supplies blood and regulates light, and the retina layer (innermost) detects light and converts it into electrical signals.

The sclera is the tough, white, outer layer of the eye, while the cornea is the transparent front covering allowing light to enter.

The choroid is a highly vascular layer that supplies blood to the retina. The iris regulates the amount of light entering the pupil.

Increased neurotransmitter release during learning strengthens the signal to the postsynaptic neuron, making the learning experience more impactful.

Repeated, small amounts of neurotransmitter release gradually bring the postsynaptic neuron closer to its firing threshold, making it more likely to fire.

Multiple synapses from the axon onto the postsynaptic neuron create a stronger connection, enhancing learning and memory.

The hippocampus, responsible for forming new memories, receives information from different parts of the cortex and sends it to the cortex for long-term storage. The cortex acts as the long-term memory bank.

Tertiary memories, formed through multiple stages of memory processing, are considered long-lasting due to the consolidation processes that ensure their survival.

The semicircular canals are fluid-filled tubes in the inner ear that help maintain balance. When the head moves, the fluid inside the canals shifts, causing the hair cells within the canals to move. These hair cells then send signals to the brain about the direction and speed of head movement.

If the semicircular canals malfunction, it can disrupt the signals sent to the brain about head movement, leading to dizziness, vertigo, and balance problems.

The olfactory epithelium is a specialized tissue located in the nasal cavity that is responsible for the sense of smell. It contains olfactory sensory neurons that detect odor molecules and transmit information to the brain via the olfactory nerve.

As we age, our taste buds start to decline, affecting our sensitivity to flavors. This decline, combined with the natural aging process of the olfactory system, often results in a diminished ability to distinguish flavors.

The cochlea is a spiral-shaped structure in the inner ear. It's designed to convert sound waves into neural signals by transforming the vibrations of different frequencies into distinct patterns of neural activity along the spiral.

Endolymph is a fluid found in the inner ear that plays a vital role in maintaining balance and hearing. Its movement within the semicircular canals helps detect head movements, and its disruption can cause issues with balance and lead to vertigo.

Vertigo is a sensation of dizziness or spinning that often results from a mismatch between information from the inner ear and the visual system. This mismatch can stem from issues with endolymph, the semicircular canals, or other inner ear components.

Conjunctivitis, also known as pink eye, is an inflammation of the conjunctiva - a clear membrane that covers the white part of the eye and the inside of the eyelid. It is often caused by infections, allergies, or irritants.

Conjunctivitis can be treated with antibiotics or eye drops, depending on the cause. Prevention includes washing hands frequently, avoiding touching eyes, not sharing personal items like towels, and cleaning contact lenses properly.

The automatic constriction of the pupil in bright light and dilation in dim light, controlled by the parasympathetic and sympathetic nervous systems, respectively.

Cones are photoreceptor cells in the retina that are responsible for detecting color and providing sharp vision. There are three types: red, green, and blue, each sensitive to different wavelengths of light.

The optic disc is the location where the optic nerve connects to the retina. It lacks photoreceptor cells, creating a blind spot because no visual information can be gathered from this area.

The vitreous body is a clear, gel-like substance that fills the space between the lens and the retina. It supports the eye's shape and allows light to pass through to the retina.

The vestibule is a part of the inner ear that senses gravity and linear acceleration, allowing us to feel motion even when stationary, like in a moving car.

The choroid is a layer of tissue that lines the back of the eye. It provides blood supply to the retina, delivering oxygen and nutrients essential for its function.

The vitreous body helps maintain the retina's position and integrity, preventing it from detaching from the back of the eye.

The otoliths are small, calcium carbonate crystals within the vestibule that shift in response to linear acceleration and deceleration. This movement stimulates hair cells, sending signals to the brain about movement.

The parasympathetic nervous system controls constriction of the pupil, aiding in normal vision by allowing for appropriate light intake.

The sympathetic nervous system controls dilation of the pupil, preparing the body for 'fight or flight' by allowing more light into the eye, aiding in vision even in low light.

A clear, jelly-like substance that fills the space between the lens and the retina, helping to maintain the eye's shape and support the retina.

A process in synapses where repeated, rapid action potentials strengthen the connection between neurons, making them more responsive to future stimulation.

Memories that fade with time and require effort to recall, like remembering a specific event from your childhood.

Memories that remain with you for a lifetime, like your own name or significant life events.

Memories lasting less than an hour, easily recalled immediately, like remembering a phone number you just looked up.

Memories lasting longer than an hour, formed through a process called memory consolidation or LTP.

The area in the brain responsible for higher learning, memory, and complex thought processes.

Damage to the cerebral cortex can impair learning and memory, affecting the ability to form and retrieve information.

Learning and refining skills involving complex motor movements, like playing an instrument, utilizes the basal nuclei, cerebral cortex, and cerebellum.

Damage to the hippocampus impairs the ability to consolidate new memories, making it difficult to convert short-term memories into long-term memories.