1. Occipital Lobe and Parietal Lobe
What are some categories of left parietal disorders?
-Apraxias (can't carry out purposeful skill movements) such as ideomotor apraxia, ideational apraxia, buccofacial apraxia, and apraxia of speech -Right/left discrimination -Gertsmann Syndrome characterized by four symptoms finger agnosia, right/left confusion, dysgraphia and acalculia
What are the four main landmarks of the occipital lobe?
-Parietal-occipital sulcus (medial surface) -Calcarine sulcus (primary visual cortex is w/i banks of this sulcus)*furthest back sulus on "point" of occipital lobe -Lingual gyrus (ventral occipital lobe) * bottom of lobe -Fusiform gyrus (ventral occipital lobe extending into the temporal lobe) *extending below both lobes
What are some categories of right parietal disorders?
-Somatosensory agnosias such as astereoagnosia and asomatognosia -Neglect symdromes such as sensory neglect, personal neglect, and motor neglect
What are some parietal disorders that do not lateralize?
-constructional apraxia -attentional impairment such as selective attention, shifting/disengaging attention -Disorder of spatial cognition (map reading, mental rotation) -Balint's syndrome characterized by a triad of symptoms including simultanagnoisa, occulomotor apraxia, and optic apraxia
What are the three functions of the dorsal visual stream?
-visuomotor guidance -visuospatial working memory -spatial navigation
What are the two main divisions of the parietal lobe?
1. Anterior Zone (Somatosensory cortex) 2. Posterior Zone (Posterior Parietal Cortex)
What are the main landmarks of the parietal lobe?
1. Central sulcus 2.Sylvian/Lateral fissure 3. Parieto-occipital sulcus
Name the 3 visual processing streams emerging from the primary/secondary visual areas
1. Dorsal Stream to superior parietal region 2. Ventral stream to the inferior temporal lobe 3. Superior Temporal Sulcus Stream
What are the different aspect of visual processing?
1. Vision for action (Dorsal stream) 2. Action for Vision 3. Visual Recognition (Ventral stream) 4. Visual Space 5. Visual Attention
Name the four parts of the distributed hierarchical and parallel processing networks
1. primary visual area (segregates color/form/motion) 2. secondary visual area (further segregates c/f/m) 3 .information proceeds to distinct cortical regions specialized for processing color (fusiform gyrus), form or motion 4. Visual processing streams to parietal, frontal, and temporal lobes
What is a visual field deficit
A loss of part of the usual field of vision causing mild visual impairment of either one eye or both depending on where the lesion may be located along the optic pathway ( between retina and occipital cortex)
The _____ Stream is known as the "where" and "how" stream because it analyzes motion and space for visual guidance of movement.
Dorsal Stream
What is the striate cortex?
It is a common name for the primary visual cortex due to the striped appearance of the multiple layers when stained ; part of the calcarine sulus
The ___ ____ ____ Stream is known as the multi-modal and sensory integration region because it bring together auditory, visual, and somatosensory inputs.
Superior Temporal Sulcus Stream
The ____ Stream is known as the "what" stream because it analyzes form and color for object perception
Ventral Stream
What is a scotoma
a blindspot in your vision ; could be in the center, around the edges or it may create arcs of light around the eye
What is achromotopsia
a hereditary condition characterized by a partial or total absence of color vision also known as total color blindness
The posterior parietal cortex (posterior zone of parietal lobe) projects to the ___, ____, and ____.
a. Thalamus b. motor cortex (guides movement) c. dorsolateral prefrontal region (maintenance of a mental representation) d. Limbic/medial temporal region (spatial navigation) e. Inferior parietal region (guiding movements)
The primary somatosensory cortex (anterior zone of parietal lobe) projects to the ____ and _____.
a. somatosensory association region (superior parietal lobule); tacile rec. b. motor cortex (primary, pre-motor, and supplemental motor regions); sensory feedback regarding limbs
What is a macular sparing
central vision is spared despite damage to the adjacent vision field
What is simultanagnosia or simultaneous agnosia
is a rare neurological disorder characterized by the inability of an individual to perceive more than a single object at a time.
What is topographical disorientation
is the inability to orient oneself in one's surroundings (even places very familiar to the person) as a result of focal brain damage.
What is visual object agnosia
it is an impairment in recognition of visually presented objects not due to a deficit in vision
What is the function of the somatosensory cortex of the parietal lobe?
processing somatosensory information and recognition of sensations
What is prosopagnosia
s a neurological disorder characterized by the inability to recognize faces.; right hemisphere disorder
What is cortical blindness
total or partial loss of vision in normal-appearing eye caused by damage to the brain's occipital cortex ; can be acquired or congenital and may also be transient; can perceive objects
What is the function of the posterior parietal cortex of the parietal lobe?
used in multi-modal sensory integration to provide neural representations of space used for visuomotor guidance , object recognition, spatial navigation, mental imagery, left/right discrimination, language, motor sequencing, attention, and eye coordination