Vision & Touch Flashcards
What are receptive fields?
Receptive fields refer to the specific region of the sensory surface that a neuron responds to.
For example, in the visual system, a receptive field may be a specific region of the retina that a visual neuron responds to.
Receptive fields can vary in size and shape, and can be arranged in a hierarchical manner in the brain.
What is single-neuron tuning for stimulus features?
individual neurons in sensory systems have preferences for specific features of the stimuli that they respond to.
For example, in the visual system, some neurons may respond preferentially to certain orientations of lines, while others may respond preferentially to certain colors. This tuning can be studied by presenting different stimuli to the neuron and measuring its response.
What do the maps of the sensory surface in cortical areas refer to?
refers to the fact that sensory information is organized spatially in the brain.
In sensory systems, adjacent regions of the sensory surface are represented by adjacent regions of the brain. For example, in the visual system, adjacent regions of the retina are represented by adjacent regions of the primary visual cortex.
How are the left and right visual fields represented in each eye?
The left visual field is projected onto the right half of the retina of both eyes.
The right visual field is projected onto the left half of the retina of both eyes.
This means that information from the left visual field is initially processed in the right hemisphere of the brain, while information from the right visual field is initially processed in the left hemisphere of the brain.
How does the primary visual cortex (V1) represent the left and right visual fields?
The information from the left visual field is processed in the right hemisphere of V1 and is represented in the right half of the cortex.
The information from the right visual field is processed in the left hemisphere of V1 and is represented in the left half of the cortex.
This arrangement is known as retinotopic mapping, where adjacent regions of the visual field are represented by adjacent regions of the cortex.
What is the optic chiasm?
A point in the visual field where the left and right optic nerves cross over to the opposite side of the brain
What is the contralateral nature of somatosensory processing in the brain?
information from one side of the body is processed in the opposite hemisphere of the brain
somatosensory information from the left side of the body is initially processed in the right hemisphere of the brain, while information from the right side of the body is initially processed in the left hemisphere of the brain.
What is transduction?
Transduction is the process by which sensory stimuli are converted into neural signals that can be transmitted to the brain for further processing.
Where does transduction occur in vision?
transduction occurs in the retina, where light is converted into neural signals.
What is the process of transduction in vision?
light is detected by photoreceptor cells in the retina called rods and cones.
The absorption of light by these photoreceptors causes a change in their membrane potential, which triggers the release of neurotransmitters that signal to downstream retinal neurons.
Where does transduction occur in touch or somatosensation?
transduction occurs in specialized receptors located in the skin, muscles, and other tissues
What is the process of transduction in touch?
receptors respond to mechanical pressure, temperature, or pain, and convert these stimuli into neural signals.
Different types of somatosensory receptors respond to different stimuli, and they can be classified into four main categories: mechanoreceptors, thermoreceptors, nociceptors, and proprioceptors.
