Vision and Eyewitness Testimony Study Guide

Regulation of central vision.

• Central vision is mostly regulated by rods.

• Central vision is mostly regulated by cones.

• Central vision is mostly regulated by the optic nerve.

• Central vision is mostly regulated by the retina.

Filllers at line-up

• non-suspects in a line-up

• suspects in a line-up

• witnesses in a line-up

• victims in a line-up

Estimator variables

• Uncontrollable events at a crime scene such as lighting at the crime

• The ability to accurately identify suspects based on prior knowledge

• The use of advanced technology to analyze crime scenes

• The psychological profile of the suspect

Rods

• Photoreceptors found in the retina. Very sensitive to low light intensity

• Cells responsible for color vision in bright light

• Neurons that transmit signals from the retina to the brain

• Photoreceptors that detect motion and depth perception

Impairment of vision in low light.

• Central vision is most impaired and cones are not activated, usually very little color is observed.

• Vision is enhanced due to increased sensitivity of rods.

• Color perception is heightened in low light conditions.

• Peripheral vision is unaffected in low light.

Optic Nerve

• Transmits visual information from the retina to the brain

• Transmits auditory information from the ear to the brain

• Transmits tactile information from the skin to the brain

• Transmits olfactory information from the nose to the brain

Iris

• Colored part of the eye. It controls the amount of light that enters the eye

• Part of the eye that focuses light onto the retina

• Outer layer of the eye that protects it from damage

• Fluid-filled space in the front of the eye

Important concepts about central vision.

• Central vision is responsible for detailed vision and relies heavily on rods for night vision.

• Central vision is primarily used for peripheral awareness and does not involve color perception.

• Central vision is responsible for detailed vision, used for tasks like reading and recognizing faces, and relies heavily on cones for color perception and sharpness.

• Central vision is mainly used for detecting motion and does not contribute to color perception.

Detectives' presence at line-ups.

• Detectives should be present to ensure the line-up is conducted properly.

• Detectives should not be present at the suspect line-up to avoid influencing the witness, either intentionally or unintentionally.

• Detectives can only observe the line-up from a distance.

• Detectives must participate in the line-up to identify the suspect.

Retina

• Contains rods and cones.

• Is responsible for producing tears.

• Is the part of the eye that focuses light.

• Is the outer layer of the eye.