Mcat Psychology Ch. 2 Sensation & Perception

Sensation refers to the raw signal of sensory information received by the body before interpretation. It is not the same as a feeling or emotion, thought or belief, or a physical reaction to stimuli.

Perception refers to how our brain interprets and organizes sensory information to make sense of the world around us. It involves complex processes that go beyond simple sensation.

Projection areas in the brain refer to specific regions where sensory information is processed and integrated. These areas are not responsible for motor control or specific sensory functions like visual processing or auditory perception, which are carried out in other specialized areas of the brain.

The Absolute Threshold refers to the minimum amount of stimulus needed to detect a particular stimulus. It is the point at which a stimulus becomes noticeable to an individual, not just the threshold to make a neuron fire.

The Threshold of Conscious Perception is the minimum level of strength or intensity a stimulus must reach in order for you to become aware of its presence. It is not related to sleep, waking up, or the processing time of a stimulus in the brain.

The Difference Threshold (Just-Noticeable Difference) refers to the minimum amount of difference needed between two stimuli for a person to detect that they are different. It is not related to the loudness of sound, reaction time, or changes in light intensity.

Weber's Law specifically deals with the relationship between the change in stimulus magnitude needed for a just-noticeable difference and the magnitude of the original stimulus, rather than the other incorrect options provided.

Signal Detection Theory refers to the idea that perception is influenced by various factors beyond just sensory input, such as past experiences, personal motives, and expectations.

Response bias refers to the tendency of subjects to respond in a particular way due to factors other than the actual stimuli presented. The incorrect answers provided describe different types of biases or errors that can occur in research studies, but they do not specifically relate to the concept of response bias.

The human eye is a complex organ with multiple components working together to enable vision. Understanding the different structures within the eye is essential for understanding how we see the world around us.

The sclera is the white outer layer of the eye that provides structural support and protection to the eye. It does not have a direct role in producing tears, controlling light entering the eye, or color vision.

The cornea gathers and focuses light in the eye by bending the incoming light rays, allowing them to pass through the pupil and lens to create a clear image on the retina.

The pupil is responsible for controlling the amount of light that enters the eye by adjusting its size, thereby allowing the passage of light from the anterior to the posterior chamber of the eye.

The iris is responsible for dividing the front of the eye into anterior & posterior chambers, controlling pupil size, and housing muscles that regulate pupil dilation and constriction based on autonomic nervous system stimulation.

The ciliary body is responsible for producing aqueous humor and changing the shape of the lens to allow us to focus on objects at different distances.

The Canal of Schlemm is responsible for draining the aqueous humor in the eye to help regulate intraocular pressure and maintain eye health.

The lens in the human eye focuses light onto the retina, enabling clear vision.

The retina is a layer at the back of the eye that contains cells sensitive to light. These cells, known as rods and cones, are responsible for detecting images and sending visual information to the brain for interpretation.

The cells of the Retina are responsible for converting light into neural signals that can be interpreted by the brain, allowing us to see. This process is crucial for vision and is essential for our ability to perceive the world around us.

Amacrine & Horizontal Cells receive input from different retinal cells to enhance the perception of contrasts and facilitate edge detection by accentuating differences in visual information from bipolar cells.

Parallel Processing involves the ability to handle multiple aspects of information simultaneously, such as shape, color, and motion. This enables the brain to process different components concurrently for efficient perception and understanding.

Parvocellular Cells are responsible for detecting shape and have high spatial resolution, but poor temporal resolution. They are not involved in functions like detecting color or brightness, controlling balance, or regulating circadian rhythms.

Magnocellular cells are specialized in detecting motion with high temporal resolution but sacrifice spatial resolution to do so.

Temporal resolution is specifically related to time and the precision with which measurements can be made in relation to time intervals.

Spatial Resolution is specifically related to the number of pixels used in an image, not the physical size, brightness levels, or color depth.

Intensity of sound is a measure of the amount of energy transmitted by a sound wave per unit area in a given direction. It is not directly related to the frequency, amplitude, or wavelength of the sound wave.

The pinna is the visible part of the ear that helps in collecting and directing sound waves into the ear canal for further processing.

The External Auditory Canal serves to direct sound waves towards the tympanic membrane, which then conducts them to the auditory ossicles in the middle ear. This process is essential for our ability to hear.

The Tympanic Membrane, also known as the eardrum, plays a crucial role in the hearing process by vibrating in response to sound waves. It acts as a barrier between the outer and middle ear, transmitting vibrations to the auditory ossicles in the middle ear. This allows for the differentiation between high and low-frequency sounds based on the rate of vibration.