Section 2 - Perception & Action Flashcards
What’s Bilateral Parietal damage?
The inability to interpret the totality of a scene & inability to control eye movement
What’s the ganglion cell?
The output of the retina
Land Retinex Theory
Colour of an object is determined by light of wavelengths reflected
What colour is a short light wavelength?
Blue
What colour is a medium light wavelength?
Green
What colour is a long light wavelength?
Red
How many different types of neurones does the retina have?
5
What are the 5 different types of neurones in a retina?
Receptors, horizontal cells, bipolar cells, amacrine cells & retinal ganglion cells
Which area is needed to be activated for colour perception?
V4
Which area is needed to be activated for motor perception?
V5
What’s akinetopsia?
Lack of motor control due to damage to the V5 Brodman area
What’s Charles Bonnet Syndrome?
intense visual hallucinations with poor/normal vision
Fovea
indentation at the centre of retina that’s specialised for high accuracy vision using only cones
Accommodation
adjusting the lease to focus image on the retina
Converge
turn inwards
Binocular disparity
difference in position of same image on 2 different retinas
Blind spot
gap in the receptor layer
What are the 2 photoreceptors?
Rods and Cones
What do Rods and Cones do?
Transduce light into electrochemical signals.
Are rods for low or normal light levels?
Low
What pigment do rods use?
Modopsin pigment
Are cones for low or normal light levels?
normal
Which pigment do cones use?
Photopsin pigment
What’s hemianopia?
Complete loss of vision in part of the visual field due to damage in the early visual pathways
What’s semi-spatial neglect?
Ignoring one side of space even when visualising a scene from memory
What’s apperceptive agnosia?
Where patients can draw an object from memory but cannot identify simple shapes
Who was the retina theory proposed by? And what does it explain?
Land to explain the colour constancy effect
What does Contralateral neglect mean?
opposite side to damage
What are the 3 principles of sensorimotor function?
Sensorimotor system hierarchy organised, motor output guided by sensory input & learning that changes the nature + locus of sensorimotor control
What’s Apraxia?
Inability to properly execute a learned skill of movement after brain damage
How many neurones does the Cerebellum have?
50million
What are the inputs for the cerebellum?
PMC, SMC & descending motor signals
What do muscle spindles do?
Embedded in muscle tissue to detect changed in muscle length to keep tension on the middle
What are the basic components of Polysynaptic reflexes?
Receptor, afferent neurone, integrating centre, efferent neurone & effector
What are the smallest unit of motor activity?
Muscles
What’s a singular motor neurone called?
Motor unit
What’s a bend/flex in a joint called?
Flexor
What straighten/extend muscles?
Extensors
What are muscles that act for some movement called?
Synergistic
What are muscles that work in opposition called?
Antagonistic
Which muscles are in the ventromedial?
Proximal
Which muscles are in the dorsolateral?
Distal
Which movements are ventrolateral?
Posture and whole body movements
Which movements are dorsolateral?
Limb movements
What are the 3 different somatosensory modalities in the Extraroceptive System?
Discriminative touch, thermal perception & nociceptive pain
Nociception
Pain
Proprioception
Knowing where you are in space
Visceral pain
Internal, diffuse & poorly located, deep & dull, automatic chemical response
Referred pain
Convergence of affronts to same dorsal horn neurones
Neuropathic pain
Damage to nerves in CNS/PNS, trauma, burning, hypoalergesia
What’s the somatosensory styes made up of? What does it do?
Receptors and processing centres to produce sensation e.g. touch
Where does the conscious processing of tactile sensation occur?
Primary Somatosensory System
Where’s the Primary Somatosensory System located?
Within the parietal lobe of the cortex of the post central gyrus.
How is the Primary Somatosensory System organised?
Soma-topically
What do the Cutaneous Somatosensory receptors do?
Traduce mechanical & thermal energies into electrical signals and trigger action potential trains that reflect into about about the stimulus
What are 2 inhibitions of pain?
Gate control theory or pain & depending inhibition
What’s the S1? And which Brodman areas?
Anterior parietal cortex with the brodman areas 3a, 3b, 1 & 2
What’s the Brodman area 3?
Receiver somatosensory input directly from thalamus
What’s the Brodman area 1?
Sensory texture & shape of object
What’s the Brodman area 2?
Size, shape and proprioception
Is somatoscensation active or passive?
Passive
Is haptics active or passive?
Active
What’s Sensory Integration?
sensory ambiguity reduced via sensory integration with multiple sensory inputs regarding the same parameter in sensory decision making
What did Ernst & Blilthoff (2002) do/state?
stated that adding different information makes different precepts more likely. Combining information from different senses can make perception more reliable.
What’s Crossmodel object recognition?
When representations of objects are shared between vision & touch
