Brain Body Behavior, The student's guide to cognitive neuroscience 100% Correct SOLUTIONS

sensation the effects of a stimulus on the sensory organs perception the elaboration and interpretation of a stimulus based on, for example, knowledge on how objects are structured retina the internal surface of the eyes that consists of multiple layers photoreceptors convert light to neural signals, and others consist of neurons themselves. they are made up of rod and cone cells rod cells cells specialized for low levels of light intensity cone cells cells that are specialized for high levels of light intensity and the detection of different wavelengths bipolar cells cells in the retina can detect light spots on dark backgrounds and dark spots on light backgrounds receptive field the region of space that elects a response from a given neuron the output of retinal ganglion cells relayed to the brain via the optic nerves the blind spot the point at which the optic nerve leaves the eye, there are no rods and cones here. the primary visual cortex the first stage of visual processing in the cortex, the region retains the spatial relationships found on the retina and combines simple visual features into more complex ones. simple cells respond to light in a particular orientation complex cells respond to light in a particular orientation but do not respond to single points of light hypercomplex cells respond to particular orientations and particular lengths hemianopia cortical blindness restricted to one half of the visual field (associated with damage to the primary visual cortex in one hemisphere) quadratanopia cortical blindness restricted to a quarter of the visual field scotoma a small region of cortical blindness retinotopic organization the receptive fields of a set of neurons are organized in such a way as to reflect the spatial organization present in the brain blindsight A symptom in which the patient reports not being able to consciously see stimuli in a particular region but can nevertheless perform visual discriminations (unaware of vision) ventral stream a pathway extending from the occipital lobes to the temporal lobes involved in object recognition, memory and semantics dorsal stream a pathway extending from the occipital lobes to the parietal lobes involved in visually guided action and attention extrastriate cortex the occipital cortex outside of V1 are called this way V4 associated with color perception V5 (or MT) associated with motion perception Achromatopsia A failure to perceive color caused by a damaged V4 Akindopsia failure to perceive visual motion color constancy the color of a surface is perceived as constant even when illuminated in different lighting conditions. V4 is important. Biological motion the ability to detect whether a stimulus is animate or not from movement cues alone figure-ground segregation the process of segmenting a visual display into objects versus background surfaces gestalt laws proximity, similarity, closure, continuity, common fate structural descriptions A memory representation of the three-dimensional structure of objects apperceptive agnosia a failure to understand the meaning of objects due to a deficit at the level of object perception associative agnosia a failure to understand the meaning of objects due to a deficit at the level of semantic memory object constancy an understanding that objects remain the same, irrespective of differences in viewing condition integrative agnosia a failure to integrate parts into wholes in visual perception object oriented agnosia an inability to extract the orientation of an object despite adequate object recognition the inferotemporal cortex (IT) takes its input from the geniculostriate pathway and appears to code the type of information important for object constancy category specifity the notion that the brain represents different categories in different ways. model of Bruce and Young model which says that after processing on a general level, a distinction between familiar faces and unfamiliar faces is made Face recognition units (FRU) stored knowledge of the threedimensional structure of familiar faces person identity nodes (PINs) abstract description of people that links together perceptual and semantic knowledge the fusiform face area (FFA) an area in the inferior temporal lobes that responds more to faces than other visual objects, and is implicated in processing facial identity face recognition differ from object recognition because they have a distinct neural substrate and can be selectively impaired prosopagnosia impairments of face processing that do not reflect difficulties in early visual analysis, patients are unable to recognize faces. categorical perception the tendency to perceive ambiguous or hybrid stimuli as either one thing or the other (rather than as both simultaneously or as a blend) within category discrimination CONTINUED.......