Perception och orientering 2? Flashcards
STS stream
Information to and from the dorsal and ventral streams converges in the STS stream.
V1 -> Superior temporal sulcus
- originates from structures associated with both the parietal and the temporal pathways and flows to a region buried in the superior temporal sulcus
- part of the multimodal cortex characterized by polysensory neurons — neurons responsive to both visual and auditory input or both visual and somatosensory input
5 general categories of vision processing
- Vision for action: category involves visual processing required to direct specific movements
* Vision for action is a function of the parietal visual areas in the dorsal stream. - Action for vision: scanning stimulus with eye movements
- more top-down process
- movements are not random but tend to focus on important or distinct features of the stimulus - Visual recognition: recognizing objects, faces, expressions, letters, symbols, etc
- specialized areas in the temporal regions for biologically significant information - Visual space: Visual information that comes from specific locations in space allows us to direct our movements to objects in those locations and to assign meaning to those objects
- Egocentric properties(objects location relative to the individual) likely coded in neural systems related to vision for action(bc necessary for action)
- allocentric properties(objects location relative to one one another) likely associated with regions of visual recognition(allocentric spatial coding is dependent on the identity of particular features in the world), and is necessary to construct a memory of spatial location - Visual attention: selecting specific aspects of visual input and attending to them selectively.
- neurons in cortex have various attentional mechanisms. Ex. may respond selectively to stimuli in particular locations or at particular times or if a particular movement is to be executed
- Independent mechanisms of attention are probably required both for guiding movements (in the parietal lobe) and for recognizing objects (in the temporal lobe).
3 areaor/hierarki för perception
Primär projektionsarea: tar emot sensorisk information
Sekundär area: tolkar information, organiserar rörelse
Tertiär area: integrerar information från sekundära areor(olika sinnessystem)
Exempel: Fotbollsmatchmetafor: primära: spelare och bollens rörelse (= enskilda delar), sekundära(fotbollsmatch), tertiära: matchens ställning och betydelse (förknippat med tidigare upplevelser, minne, emotion)
Dom sa dock också att det ej fanns några bevis för att detta e hur perception faktiskt funkar så idk varför dom ens berättade om det då
Vilken lob e främst associerad med de olika sinnena
Lukt = frontal
Hörsel = temporal
Smak = frontal
Syn = occipital
Känsel = parietal
Vad gör v1, v2, v3 och v5
Primär = striate cortex snabb och tidig bearbetning/tolkning
Sekundär = Extrastriate cortex
V2 = för vidare/delar upp information
V3 = rörelse och form
V5 = rörelse
Vanliga visuella funktionsnedsättningar orsakade av skador i ventrala respektive dorsala strömmen
Ventrala: olika typer av visuell agnosi (inkl. prosopagnosi)
Dorsala: hemispatialt neglekt, simultanagnosi, apraxi - oförmåga att planera och utföra viljemässiga rörelser trots fungerande funktion (olika typer: ideomotorisk apraxi, konstruktionsapraxi)