Cerebral Cortex 4

Visual Association Cortex Higher-Order Visual Processing Dorsal pathways to parieto-occipital association cortex –Where? Ventral pathways to occipitotemporal association cortex –What?

Primary Visual Cortex Injury Unilateral –Homonymous hemianopsia with macular sparing Bilateral –Cortical Blindness – Anton’s syndrome Anosognosia

Inferior occipitotemporal association cortex What stream of visual analysis –Process color and visual form Prosopagnosia –Bilateral injury to inferior occipitotemporal cortex –Can describe, but cannot identify –Generic recognition - intact –Specific recognition - impaired

Dorsolateral Parieto-occipital cortex Where stream of visual analysis

Balint’s Syndrome Simultanagnosia Optic Ataxia Ocular apraxia

Attention/Awareness Brain regions –Brainstem reticular formation –Thalamus –Basal forebrain –Cerebral cortex

Memory Three types of memory –Emotional –Declarative –Procedural

Emotional Memory Memory of feelings Memory for fear is in the amygdala Brain regions not known for other emotions

Declarative memory AKA conscious, explicit, cognitive memory Memory for facts, events, concepts and locations Requires attention during recall

Three stages Immediate (sensory register) –1 to 2 seconds –Memories can be easily displaced –Primary sensory and sensory association cortex Short-term memory –Brief storage –Begins to be lost in 1 minute if not rehearsed Long-term memory –Relatively permanent –Consolidation (ST  LT)

Neuroanatomy of Declarative Memory Sensory Association Areas Anterior Temporal Lobe Parahippocampal Cortex  Hippocampus Basal forebrain, including basal nucleus of Meynert Cerebral Cortex

Problems with Declarative Memory H.M. – bilateral removal of medial temporal lobe including the hippocampus –Consolidation lost Cannot form new long-term memories No memory for events since the surgery No memory for events less than one year before the surgery –Earlier memories intact –Can learn skills

Procedural Memory AKA Skill, habit, nonconscious memory, implicit memory Requires practice Task can be done without conscious thought

Three stages of Procedural Memory Cognitive –Beginning stages –Person thinks about what they are doing – cognitive –Step-by-step performance of task Associative –Movements refined and more efficient –Less dependent on cognition

Autonomous stage –Movements are autonomous, do not require attention or conscious thought –Other activities can be done at the same time Walk and chew gum Cook and talk

Procedural Memory Location –Frontal cortex –Thalamus –Basal ganglia