Exam II Flashcards
Ultrasound
frequencies higher than the upper audible limit of human hearing
bats use high-frequency cries to listen for weak ultrasonic echoes reflected back from objects in their flight path
Infrasound
sound waves with frequencies below the lower limit of human audibility
Camera eye
like human, with lens for focus
Pinhole Eye
Pinhole – no lens - uses small hole to control light – no focus control greater field of vision
Brainstem
Brainstem breathing, temperature control hormone control, initial sensory info
Cerebral Cortex
large forebrain, sensory processing, initiating movement, cognition, emotion, reasoning
Neurons
a specialized cell transmitting nerve impulses; a nerve cell.
Glia
non-electrically active brain cells
support neurons structurally and chemically
Motor Neurons
sends commands to muscle fibers
Sensory Neurons
sensory neural systems encode, organize and decode information from the environment
processes sensory info(light, pressure, sounds)
Neuron Communication
x
Motor Unit
Motor unit – one motor neuron and the muscle fibers that it innervates
Myelin
Myelin – glia that wrap around axons, speed action potential travel
Myelin is most dense in somatosensory and motor cortex
Motor Program
Motor Program – stereotyped sequence of motor behaviors to accomplish one overall behavior - automatic in quality and is critical to survival (e.g. Tritonia escape swimming)
Cortical Magnification/Hypertrophy
Brain Hypertrophy – increase in size of specific regions of the brain due to an extraordinary sensory or motor capacity
Also called “expanded representation” or “magnification”
ex: star-nosed mole
Phonotaxis
Phonotaxis = orienting based on acoustic cue
Reactive steering
Reactive Steering: movements right or left in response to an orienting stimulus
Sensory and Motor Cortex
Sensory and motor cortex Somatosensory and motor cortex are organized by body part. Myelin is most dense in somatosensory and motor cortex
Cortical Magnification
Cortical magnification describes how many neurons in an area of the visual cortex are ‘responsible’ for processing a stimulus of a given size, as a function of visual field location.
see ex. Neuro 2
Command Neuron
Command neurons: single or small group of interneurons that are both necessary and sufficient to initiate stereoptyped motor pattern
CNS/PNS
CNS: brain and spinal cord
sensation, perception, cognition, reasoning, emotion, motor
PNS: nerves and ganglia outside the brain and spinal cord
nerves - receptors, sensory, motor
carry info to and from brain
Motor Program
A motor program is an abstract representation of movement that centrally organizes and controls the many degrees of freedom involved in performing an action
Central Pattern Generator
A group of cells in the CNS that produce a particular pattern of signals necessary for a functional behavioral response
the neural clusters in a central pattern generator play a preprogrammed set of messages that help organize the motor output of a FAP
Phase Locking
fish midman; female becomes more sensitive to the harmonics of male hum by phase locking to them
locking to wave forms, helps reception
distance of curve
T and E2 treated fish show higher VS to higher frequencies than do controls
The hormone-induced increase in VS to higher frequencies matches the harmonics of the male’s mating hum.