Flashcards
Module Two
Flashcards do conjunto (115)
- 1SensationA stimulus detection process involving sensory organs translating environmental stimuli into electrical impulses (receiving sensor info)
- 2PerceptionActive processing and organising of stimuli and assigning it meaning (making sense of the sensation)
- 3Neural Implementation1. Sensory Organ absorbs energy
2. Energy is transduced into a neural signal (action potential)
3. The neural signal is sent throughout the brain for further processing - 4Parts of the eye for protection:Sclera
Cornea - 5Aqueous HumourNutrition/structural
- 6Extraocular MusclesMovement
- 7ChoroidProduces light scatter
- 8Iris/PupilIris reacts to light sensation
- 9LensFocuses the light ----> fovea
- 10Ciliary Body/MusclesStretches
- 11Vitreous HumourJelly
- 12RetinaAbsorbs energy into electricity
- 13Optic NerveSends information into brain
- 14The visible spectrum is a ______ portion of the electromagnetic spectrumSmall
- 15Wavelength =Colour
- 16Amplitude =Brightness
- 17Layers of the RetinaPhotoreceptors (rods and cones)
Bipolar Cells
Retinal Ganglion Cell - 18PhotoreceptorsTransduce light into neural activity using opsin proteins
- 19Two types of photoreceptorsRods
Cones - 20RodsBlack and White vision
Use at night
Low resolution
High sensitivity
More amount than cones
Spread around the peripheral of retina
Rhodopsin - 21ConesColour Vision
Use during the day
High resolution
Low sensitivity
Less amount than rods
Around fovea
Cone opsin - 22Bipolar CellsRelay activity to retinal ganglion cells. Half also complete signal inversion
- 23Retinal Ganglion Cells (RGC)Relay sensory information to brain. Begin processing visual information
- 24Process of Seeing:Light > Cornea > Lens > Photoreceptors > Bipolar Cells > Ganglion Cells > Optic Nerve > LGN > V1
- 25Is information from visual space is processed on the opposite or same side of the brain?Opposite
- 26LGN and V1 are organised via ________ mappingRetinotopic
- 27Retinotopic MappingPoint to point mapping of the external world onto the retina
- 28What type of processing occurs after V1?Divergent - visual information takes two streams
- 29Mishkin, Ungerleider & Macko ExperimentTraining of monkeys in two tasks
Object Discrimination and Landmark Discrimination - 30Temporal Lobe damage affects...Object discrimination tasks (knew where not what)
- 31Parietal Lobe damage effects...Landmark discrimination tasks (what, not where)
- 32Ventral Stream= Temporal cortex = what (objects, colour, patterns etc)
- 33Dorsal Stream= Parietal Cortex = where (spatial location and movement)
- 34The 'Grandmother Cell' hypothesis:There is a single neuron in your temporal lobe which responds to every different complex visual stimulus
- 35Is the Grandmother Cell Hypothesis true or false?False
- 36Receptive FieldsEarlier visual neurons (before V1 diverges) respond only to stimuli in a particular location in visual space
- 37Rods and Cones preferred stimuli:Diffused darkness
- 38Bipolar Cells preferred stimuli:Diffused darkness
- 39Retinal Ganglion Cells preferred stimuli:Spots of dark/light
- 40LGN Neurons preferred stimuli:Spots of dark/light
- 41V1 neurons preferred stimuli:Angled Lines
- 42Centre-Surround StructureEnhances visual contrast
- 43For on centre cells, stimuli that lands on the centre _____ it, while stimuli that hits the surround, _______ it.Activates, Inhibits.
- 44Lateral Inhibition:The capacity of an excited neuron to reduce the activity of its neighbours . The spread of APs from excited neurons in lateral directions is inhibited. This enhances contrast, allowing for increased sensory perceptions.
- 45What creates the Herman Grid IllusionLateral Inhibition
- 46High contrast stimuli are enhanced by:Lateral Inhibition between cells (horizontal connections)
Centre surround structure of a single cell (vertical connections: bipolar-RGCs) - 47AnopiaBlindness - caused by damage to the visual pathways
- 48BlindsightCan localise objects, but swear they cannot see.
Damage to V1
LGN cells bypass V1 and synapse directly onto V2 or later - 49AchromatopsiaLoss of colour
Damage to inferior temporal cortex and V4 - 50AkinetopsiaLoss of perception of emotion (see the world in screenshots)
Damage to middle temporal visual cortex (V5) - 51Agnosia (disorder of perception)See fine, but are unable to recognise or perceive visual stimulus
- 52Apperceptive AgnosiaGlobal Deficit in perception
Unable to name objects
Poor Shape Matching and copying - 53The Peppery Mask HypothesisWidespread, diffuse damage across V1 caused by hundred of little blind spots
i.e. CO2 poisoning or Alzheimers disease - 54Two forms of SimultanagnosiaDorsal
Ventral - 55SimultanagnosiaUnable to recognise multiple objects
- 56Dorsal Simultanagnosia (worse)Unable to perceive/recognise more than one object at a time
Damage is typically bilateral and in parietal/occipital regions - 57Ventral SimultanagnosiaUnable to identify more than one object at a time, but aware there are multiple objects
Damage is typically in the left hemisphere and in inferior temporal/occipital cortex - 58Associative AgnosiaA specific deficit of recognition
CAN match shapes and copy
Whilst accurate, copying is slavish
Degraded perception
Damage usually involves inferior/posterior temporal lobe
"The man who mistook his wife for a hat" - 59Bottom Up Theories (direct)Start broken, build up together - build to form the overall understanding
This is how the visual system works - 60Top Down Theories (indirect)Start with a hypothesis of the big picture, is then broken down into little details
The visual system forms hypothesis of what it is seeing based on past experiences and prior knowledge - 61Evidence for Top Down TheoriesWe can recognise stimulus faster than we could process information
We can read faster then we can process, and use contextual information to make sense of misspelled words
We are able to switch between a bistable percept
We are able to perceive contours that aren't there but would complete and object - 62Interactive TheoriesIncorporate both theories during perception
E.g The Perceptual Cycle Theory - 63Evidence for Interactive TheoriesWhen we are exposed to a stimulus longer and when the stimuli is clearer, there tends to be less error.
The visual system is actually built with up and down pathways - 64Two forms of Depth PerceptionBinocular Cues
Monocular Cues - 65Binocular Cues (two eyes)Contribute to depth perception via eye vergence
Cross eyed: convergence
Wide eyes: divergent - 66Retinal DisparityThe space between the eyes that means the angle of viewing an object is slightly different for each eye
Processed in V1
Useful for objects 10m from the eye
How 3D glasses create the illusion of 3D - 67Monocular Cues (one eye)Contribute to depth perception when viewing 2D images
- 686 Types of Monocular Cues1. Linear Perception
2. Interposition
3. Height in Plane
4. Texture Gradient
5. Relative Size
6. Light/Shadow Patterns - 69Colour Perception TheoriesThe Young-Helmholtz Trichromatic Theory
The Opponent- Process Theory - 70The Young-Helmholtz Trichromatic TheorySuggested that colour perception is made up of 3 different types of cones processing 3 wavelengths of light (short, medium, long)
Problems with this:
Why does colour blindness occur in pairs?
Unable to explain negative colour after images - 71The Opponent-Process TheorySuggests that colour perception is controlled by 3 opponent systems that detect the relative amount of light at different wavelengths
- 72Colour Perception Current Thoughts:Both retinal trichromacy and colour opponency circuits contribute to our perception of colour
- 73Localisation of Function:Different areas of the brain are responsible for different functions
- 74The Edwin Smith Surgical PapyrusRecognised the relationship between the location of the brain injury and the resulting specific neurological deficits
- 75AristotleThought that brains role was to cool blood
- 76AlcmaeonThought that the brain was the 'organ of the mind'
- 77150-1500s experts focused on:The substances within the cerebral ventricles and were 'spirit based'
- 78DescartesConsidered the Pineal Gland to be the principal seat of the soul
(not true) - 79Luigi RolandoWhite matter tracts link brain regions
- 80Gall & SpurzheimThe idea of Phrenology
- 81FlourensThe idea of cerebral 'equipotentiality'
- 82BrocaRealised that speech function is localised within the brain
- 83Fritsch & HitzigThe importance of electricity and the motor strip
- 84Santiago Ramon y CajalNeuron Doctrine and used Tracing
- 85Brodmanns MapDifferent areas of the cortex have different organisations
- 86War DoctorsShrapnel injuries allowed them to localise V1 and produce retinotopic maps
- 87Wilder PenfieldMapped the primary motor and sensory cortex by being electrically stimulated during surgery. Motor Homunculus
- 88Methods of Localising function in later 20th Century:Stimulation
Anatomical Connectivity
Recording Neural Activity
Lesions (brain damage or surgery)
Behavioural Testing - 8921st Century Localisation of FunctionBrain imaging and genetic methods of stimulation and anatomy
i.e. Dayu Lin's research using laser stimulation of genetically targeted neurons - 90Current View is more supportive of:Regionalisation than equipotentiality
- 91Combining multiple different experiments provides the ____ evidence for localisation of functionBest
- 92Damage to the Superior Temporal Gyrus (STG): (hearing)Corticol Deafness (blindsight)
Auditory Agnosias - 93Left Posterior STG damage:Wernickes Aphasia
Understanding tone and rhythm, but unable to understand meaning - 94Right Posterior STG damage:Aprosodia
Cannot understand prosody (rhythm and intonation of speech) - 95Middle and Inferior Temporal Gyri: Visual ImpairmentsAchromatopsia
Akinetopsia
Associative Agnosia
Ventral Simultanagnosia - 96Fusiform GyrusProsopagnosia: face blindness > can see everything EXCEPT FACES
- 97Medial Temporal Lobe (MTL)Memory Impairments
- 98Right MTLVisual Memory
- identify and copy visual stimulus, unable to reproduce them - 99Left MTLVerbal Memory
- Struggle to remember verbal information - 100Damage to S1Vibration, Fine touch, Proprioception are impaired
- 101AstereognosiaLoss of touch based sensation
- 102Parietal Lobe beyond S1: sensory integration and movement. Deficits in:Abstract Concepts
Processing Spatial Information
Directing Attention
Integrating Sensory Information
Guiding Movements to a particular point in space
Object guided hand movements - 103Left Parietal Lobe:Reading and Writing
-Agraphia (writing)
-Alexia (reading)
Acalculia (maths)
Symptoms:
Finger anomia
Left and right confusion
Unable to draw details - 104Right Parietal Lobe:Visual and Drawing
Symptoms:
Unable to draw overall shape of objects
Struggle to recognise unfamiliar view of objects - 105Contralateral NeglectThe inability to perceive or attend to objects, even one's own body, on the LEFT side (opposite to side of brain damage)
- 106Tests of Contralateral NeglectLetter/line cancellation
Line bisection
Finger wiggling - 107AnosognosiaA lack of awareness of their own inability
- 108Evidence of Contralateral NeglectThe Burning House Anecdote
The Milan Piazza Experiment - 109Is Contralateral Neglect Ego-Centric or Object-Centered?Both/Either
- 110Evidence of Egocentric vs Object CenteredThe Broken Hearts Test
Draw or Copy Two People Experiment - 111Why is left sided neglect most common?Because the right hemisphere of the brain is suggested to be specialised for global visuospatial processing
- 112Damage to the Primary Motor Cortex (M1)Paralysed or partial paralysis on opposite side of the body to the brain damage
Problems with fine movement, speed, and strength of movement - 113Damage to Premotor CortexImpaired motor planning
Brocas aphasia - 114Left premotor Cortex damageUnable to speak fluently
- 115Damage to prefrontal cortexImpaired divergent thinking
Impaired response inhibition
Environmental Dependency Syndrome (imitation and utilisation)
Changes in personality (picks disease, Phineas Gage)
Informações
- Descrição
- FlashCards sobre Module Two, criado por Nina James em 15-06-2018.
- Criado por
- Nina James · jun 2018
- Atualizado
- 16 jun 2018
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