memory 2 psb 5341. the temporal lobes and declarative memory the diencephalon and memory processing...
TRANSCRIPT
The Temporal Lobes and Declarative Memory
• The Diencephalon and Memory Processing– Diencephalon: Brain regions associated with memory
and amnesia (outside the temporal lobe)
Large lesion to anterior nucleus & dorsomedial nucleus of the thalamus in monkeys causes deficits in DNMS performance. Lesions to either structure alone, lead to milder deficits. Even milder deficits occur after lesions to mammillary bodies.
The Temporal Lobes and Declarative Memory
• The Diencephalon and Memory Processing– Korsakoff’s Syndrome
• Symptoms: Confusion, confabulations, severe memory impairment, and apathy
– Alcoholics: Develop thiamin deficiency • Leads to symptoms: Abnormal eye movements,
loss of coordination, tremors
– Treatment: Supplemental thiamin • Thiamin deficiency: Structural brain damage
The mediotemporal lobe has important role in declarative memory or consolidation.
Severe anterograde amnesia results after mediotemporal lobe lesions.
Hippocampus itself important. In both animals & humans, the same stimulus elicits a different response when familiar than unfamiliar.
Recordings from single cells from human hippocampus in Fig 24.14 as part of surgery for epilepsy.
The Temporal Lobes and Declarative Memory
• Memory Functions of the Hippocampus– Role of the medial temporal lobes
• Declarative memory processing or consolidation
The Temporal Lobes and Declarative Memory
• Memory Functions of the Hippocampus– Spatial Memory and Place Cells
• Morris water maze
The Temporal Lobes & Declarative Memory
• Memory Functions of the Hippocampus– Spatial Memory, Working Memory, and
Relational Memory• Relational memory• Highly processed sensory information
– To hippocampus and nearby cortex
The Striatum and Procedural Memory
• Two elements of basal ganglia Striatum– Caudate nucleus – Putamen
• Rodent Recordings and Lesions in the Striatum– Lesions to striatum: Disrupts procedural memory – Damaged hippocampal system: Degraded
performance on standard maze task– Lesion in striatum: Impaired performance of the light
task; Double dissociation
The Striatum and Procedural Memory
• Habit Learning in Humans and Nonhuman Primates – Striatum in humans plays a role in procedural
memory
The Neocortex and Working Memory
• The Prefrontal Cortex and Working Memory – Primates have a large frontal lobe – Function of prefrontal cortex: self-awareness,
capacity for planning and problem solving
The Neocortex and Working Memory
• The Prefrontal Cortex and Working Memory (Cont’d)– Imaging Working Memory
in the Human Brain • Numerous areas in
prefrontal cortex are involved in working memory
The Neocortex and Working Memory
• Lateral Intraparietal Cortex (Area LIP) and Working Memory – Area LIP: Guiding eye movements – Delayed-saccade task
Concluding Remarks
• Learning and memory– Occur throughout the brain
• Memories– Duration, kind of information stored, and brain
structures involved – Distinct types of memory– Different types of amnesia
• Multiple brain systems for memory storage
• Engrams in temporal lobe neocortex – Physiological basis?– Long-term memories: structural basis?