Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

KNES 371 Exam 2 > Ch. 4 > Flashcards

Ch. 4 Flashcards

1
Q

Proprioception

A

Body parts relative to each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Exproprioception

A

body and its various parts relative to environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Exteroception

A

visual layout and relative position of objects in space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Iris activity indicate

A

ANS function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Cone cells

A

fovea
high levels of illumination; day vision
Many sensory nerve fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Rod cells

A

peripheral retina, nearest lens
poorly lit conditions; night vision
Single sensory nerve fiber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Visual Processes

A

Light waves are transducer into electrical impulses by rod and/or cone cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Transmission to the Brain

A

Electrical impulses leave the eye via the optic nerve

  • Optic tracts arise from the optic nerve- relays impulses to the thalamus
  • Partial crossing at optic chasm- allows three dimensional viewing, binocular viewing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Transmission to the Brain (2)

A

Most information travels via thalamus to the primary visual cortex: organizes the scene; contrast and form
Some info goes to the superior colliculus (SC) in midbrain: Reflexive control of eye and head movements. Also plays an important role in attention and visual perception / integration with other sensory information
Visual association areas: final perception of the external world

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Accommodation

A

Ability of lens to focus

Declines with age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Visual Acuity

A

Discern detail

Factors affecting visual acuity include contrast, lighting, time, motion, age, color, attentional demands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Dynamic Visual Acuity

A

More important in sports
Improves from ages 6-20; vision becomes adult-like between ages of 10-12 but then begins to decline
DVA can be improved in adults with training

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Eye movements

A 
Involuntary:
vestibular ocular reflex
optokinetic reflex
Voluntary:
smooth pursuit
saccades
vergence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Vestibulo-Ocular Reflex

A

The automatic generation of eye movements from movements of the head
Signals from he semicircular canals are sent directly as possible to the eye muscles
Using these direct connections, eye movements lag the head movements by less than 10 ms, one of the fastest reflexes in the human body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Optokinetic Reflex

A

Allows the eye to follow objects in motion when head remains stationary
To help achieve a stable retinal imagine
Complimentary to the VOR
Has a longer latency and most responsive at lower frequencies (0.1 HZ) of head movements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Smooth Pursuit

A

Keeps moving object fixed on fovea

Speed voluntarily determined

17
Q

Saccades

A

Quick shifts

Angular distance between objects determines speed

18
Q

Vergence

A

eyes move in opposition
Convergence
Divergence

19
Q

Two visual systems?

A

Two structurally distinct pathways, leading to different areas of the brain suggest existence of two visual systems:
Focal system: what
Ambient system: where

20
Q

Focal System

A

Responsible for identification of objects in the center of the visual field
Involved the fovea of the eye; high visual acuity
Best in bright light

Involves conscious though
Pathway leading to primary visual cortex is responsible for this type of visual processing

21
Q

Ambient System

A

Used for detecting space around the boy while providing information about where objects are in space
Involves the entire retina
Best in dim light

Involves subconscious processing
Helps prevent collisions while walking busy street

22
Q

Two Visual Systems working together

A

Appear to work in parallel in most movement situations:
Focal system: assists in identifying objects in the space
Ambient systemL is used to locate objects in space at a subconscious level and orient the body during movement
Two systems allows us to attend to different forms of visual input at the same time

23
Q

Theories of Visual Perception

A

Two different theories for Visual Perception:
Cognitive or Indirect theory
Ecological or Direct theory

24
Q

Indirect Theory

A

(Cognitive)
Visual perception is based on one’s understanding of the environment through deductive internal processes
Requires cognitive activity, thus perception is indirect - NOT directly apparent from the visual scene

25
Q

Direct Theory

A

Visual information can be directly extracted from the environment
The optic array provides all the necessary information to guide movement
Does not require any intervening cognitive processes to determine meaningfulness

26
Q

Which theory is best?

A

Research supports both theories:
Indirect theories best to explain movement governed by a set of rules (sport)/dynamic environment or situations with anticipation
Direct theories best in stable environments/standing upright, moving through space, interception a moving object in a stable environment

27
Q

Visual Guidance of Action:

Indirect theory assumption

A

Indirect theories assume that the visual system provides system provides predictive information early in an objects flight by which to determine when to initiate action

28
Q

Visual Guidance of Action: Direct theory assumption

A

Assume that visual information is continuously used to monitor the object’s flight using optic tau
Time-to-time contact information

29
Q

Visual Guidance of Action: Visual Dominance

A

over all other sensory systems as source of sensory feedback, even when it provides inaccurate information
Can have a negative effect: sensory conflict, situation requiring a rapid response; rely less on somatosensory cues

30
Q

Vestibular Apparatus

A

The VA constists of Utricle, Saccule, and Semicircular canals
Utricle: horizontal acceleration of head
Saccule: vertical acceleration of head
Semicircular canals: angular acceleration
Contributes to static and dynamic equilibrium and resolution of sensory conflicts

31
Q

Ascending Pathways

A

From vestibular nuclei to thalamus, cortex, cerebellum, spinal cord and oculomotor nuclei
Spatial orientation

32
Q

Descending Pathways

A

From vestibular nuclei to spinal cord

Postural control

33
Q

Vestibular Contributions to Actions

A

Works collaboratively with the visual system and the somatosensory system to :
maintain posture (reflexive role in balance)
stabilize vision when the head is moving

KNES 371 Exam 2 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions