Guide d'étude de l'examen final
SECTION 9
What is the difference between learning and memory? (definitions)
Learning is the acquisition of new information or knowledge through experience, instruction, or study. Memory, on the other hand, refers to the ability to retain and retrieve information that has been learned or experienced in the past.
Main kinds of memory: declarative & non-declarative
Declarative memory refers to conscious memories that can be explicitly stated, such as facts and events. Non-declarative memory, also known as implicit memory, refers to unconscious memories that are expressed through performance, such as skills and habits.
What is the difference between long- and short-term memory?
Short-term memory is a temporary storage system for information that lasts for seconds to minutes, whereas long-term memory is a more permanent storage system for information that can last for days, months, or even a lifetime.
The case of H.M.: What kind of memory loss was he suffering from? What kind of brain damage led to his amnesia?
H.M. suffered from severe anterograde amnesia, which is the inability to form new long-term memories after the onset of amnesia. His amnesia was caused by surgical removal of the medial temporal lobes, including the hippocampus.
What kinds of memory systems are spared in cases of amnesia like H.M.’s? (be familiar with specific examples of tasks from the book and notes).
Memory systems that do not depend on the medial temporal lobes, such as procedural memory (e.g., learning how to ride a bike), are often spared in cases of amnesia like H.M.’s. For example, H.M. was able to improve his mirror-drawing skills over time despite not remembering practicing the task.
What is the difference between anterograde and retrograde amnesia?
Anterograde amnesia is the inability to form new long-term memories after the onset of amnesia, whereas retrograde amnesia is the loss of previously formed long-term memories, often for events that occurred before the onset of amnesia.
How can the damage to the medial diencephalon cause amnesia?
The medial diencephalon, which includes the thalamus and mammillary bodies, is connected to the medial temporal lobes and plays a crucial role in memory consolidation. Damage to the medial diencephalon can disrupt communication with the medial temporal lobes, leading to amnesia.
What kind of brain damage is observed in patients with Korsakoff’s syndrome? What type of memory deficits do these patients have?
Patients with Korsakoff’s syndrome often have damage to the medial diencephalon and frontal lobes, particularly the prefrontal cortex. They have severe anterograde amnesia and may also have retrograde amnesia, as well as confabulation (the production of false memories) and other cognitive deficits.
Can brain damage destroy autobiographical memories while sparing general memories?
Yes, brain damage can selectively impair autobiographical memories while leaving other types of memories relatively intact. For example, patients with damage to the ventromedial prefrontal cortex may have difficulty recalling personal experiences and emotions but have preserved general knowledge.
What is the difference between skill learning, priming, and conditioning?
Skill learning refers to the acquisition of new motor or cognitive skills through practice, such as playing a musical instrument. Priming refers to the facilitation of processing for a stimulus that has been previously encountered, such as reading a word more quickly the second time it appears. Conditioning refers to the learning of associations between stimuli or between a stimulus and a response, such as Pavlovian conditioning.
What is the difference between free recall, cued recall, and recognition memory?
Free recall is when a person is asked to remember information without any cues or prompts.
Cued recall is when a person is given a cue or prompt to help them remember the information.
Recognition memory is when a person is presented with a previously seen item among a set of novel items and asked to identify the previously seen item.
Does long-term memory have a limit? Is it perfectly accurate or is it subject to distortions? What kinds of distortions?
Long-term memory has a large but not infinite capacity, and it is not perfectly accurate. It is subject to various types of distortions such as forgetting, false memories, and source monitoring errors.
What brain mechanisms are involved in memory encoding, storage, and retrieval?
Memory encoding involves the consolidation of information from short-term memory to long-term memory, which is mediated by changes in synaptic strength and protein synthesis. Memory storage involves the maintenance of information in long-term memory, which is supported by the hippocampus and other cortical regions. Memory retrieval involves the activation of stored information, which is mediated by the prefrontal cortex and other brain regions.
What is semantic memory? How does it differ from episodic memory?
Semantic memory is a type of long-term memory that stores general knowledge about the world, including concepts, facts, and relationships between things. It differs from episodic memory, which stores personal experiences and events that have a specific time and place.
Is semantic memory affected in amnesia?
Semantic memory is generally spared in cases of amnesia, such as in the case of H.M. and other patients with medial temporal lobe damage.
What brain systems are presumed to support semantic memory?
The ventral and lateral regions of the prefrontal cortex, along with the anterior temporal lobe, are presumed to support semantic memory.
What does the term ‘memory consolidation’ refer to?
Memory consolidation refers to the process by which new memories are stabilized and strengthened in long-term memory over time, through changes in synaptic strength and protein synthesis. This process is thought to involve the hippocampus and other brain regions, and it is critical for the formation of enduring memories.
What is the difference between synaptic and system consolidation?
Synaptic consolidation refers to the process of strengthening the connections between neurons that are activated together during learning, while system consolidation refers to the process of transferring memories from the hippocampus to the neocortex, where they can be stored in a more stable and long-lasting form.
What is long-term potentiation? How does it relate to the function of the hippocampus?
Long-term potentiation (LTP) is a process of synaptic strengthening that occurs when two neurons are repeatedly activated together. LTP is thought to be a cellular mechanism that underlies learning and memory, and it has been extensively studied in the hippocampus, which is a brain region critical for learning and memory.
What kind of changes at the synaptic level support learning and memory?
Learning and memory are supported by changes in the strength and connectivity of synapses, which can be achieved through various mechanisms such as long-term potentiation (LTP), long-term depression (LTD), and structural changes in dendritic spines.
What is the function of medial temporal structures for declarative memory?
The medial temporal lobe (MTL) structures, including the hippocampus, parahippocampal cortex, and entorhinal cortex, are essential for the formation and retrieval of declarative memories, which are memories for facts and events that can be consciously recalled.
What is the contribution of hippocampal mechanisms to spatial memory?
The hippocampus plays a critical role in spatial memory, which is the ability to remember and navigate through an environment. Studies in rodents and humans have shown that the hippocampus is necessary for spatial learning and memory and that damage to the hippocampus impairs spatial navigation.
What brain structures support skill memory, repetition priming, and conditioning?
Skill memory is supported by the basal ganglia, a set of subcortical structures that are involved in motor control and learning. Repetition priming, which refers to the improved ability to identify a stimulus that has been previously encountered, is supported by the neocortex. Conditioning, which is the association of a stimulus with a particular outcome, is supported by the amygdala and other brain regions.
Summary graph: Brain regions involved in learning and memory
The summary graph shows that different brain regions are involved in different aspects of learning and memory, including the prefrontal cortex, basal ganglia, amygdala, hippocampus, and neocortex.
How do young and older adults differ in terms of their dependence on recall or recognition memory strategies? What kinds of brain structures differentially support these strategies?
Older adults tend to rely more on recognition memory than recall memory, whereas younger adults use both strategies equally. This difference may be related to changes in the prefrontal cortex, which is involved in executive control and working memory.
What is the main symptom of semantic dementia? What kind of brain damage is associated with the disorder?
The main symptom of semantic dementia is a progressive loss of semantic knowledge, which refers to the ability to understand and use words and concepts. This is associated with damage to the anterior temporal lobe, including the fusiform gyrus and temporal pole.
SECTION 10
What is the difference between attention and arousal?
Attention refers to the cognitive process of selectively attending to specific stimuli or features in the environment, while arousal refers to the physiological state of alertness and readiness to respond to stimuli.
What brain system is responsible for maintaining overall arousal levels?
The ascending reticular activating system (ARAS) in the brainstem is responsible for maintaining overall arousal levels.
What is the role of the cholinergic system in arousal and attention?
The cholinergic system, which involves the neurotransmitter acetylcholine, plays a role in both arousal and attention. It is involved in the maintenance of arousal and also in enhancing attentional processing.
What is the role of the noradrenergic system (in particular the locus coeruleus) to arousal?
The noradrenergic system, which involves the neurotransmitter norepinephrine, is involved in maintaining overall arousal levels, and in particular the locus coeruleus plays a key role in this process.
Structures of the thalamus critical for arousal
The intralaminar nuclei of the thalamus, including the centromedian nucleus, parafascicular nucleus, and central lateral nucleus, are critical for arousal.
What is the role of the thalamus in sustained attention?
The thalamus is involved in sustaining attention by relaying sensory information to the cortex and also by modulating activity in the cortex.
What is the difference between top-down (or endogenous) and bottom-up (or exogenous) attentional selection?
Top-down attentional selection refers to the deliberate allocation of attention based on prior knowledge, expectations, or goals, while bottom-up attentional selection refers to the automatic capture of attention by salient or novel stimuli in the environment.
What are the main tenets of early and late selection models of attention and what is the evidence in favor of each (specifically EEG & ERP evidence)?
Early selection models of attention propose that attentional selection occurs before sensory processing, while late selection models propose that selection occurs after sensory processing. EEG and ERP evidence supports both models, suggesting that the timing and extent of attentional selection may depend on task demands and stimulus characteristics.
What is the role of the superior colliculi in selective attention?
The superior colliculi play a role in selective attention by directing eye movements toward relevant stimuli in the environment.
What is the role of the thalamus in selective attention?
The thalamus is involved in selective attention by filtering sensory information based on attentional demands and modulating activity in the cortex.
Top-down attention modulation: The intraparietal sulcus
The intraparietal sulcus is involved in top-down attention modulation, particularly in the allocation of attention to spatial locations and the selection of relevant stimuli.
Is there a difference between the contributions of the left and right hemispheres in attention?
Yes, there is a difference in the contributions of the left and right hemispheres in attention. The left hemisphere is more specialized for attention to stimuli on the right side of the body or in the right visual field, whereas the right hemisphere is more specialized for attention to stimuli on the left side of the body or in the left visual field.
What is the role of the superior parietal lobe in selective attention?
The superior parietal lobe plays a critical role in selective attention by directing attention to specific locations in space. It integrates information from different sensory modalities and generates a spatial map that guides attention.
The anterior cingulate cortex and its role in selective attention and monitoring.
The anterior cingulate cortex (ACC) plays a key role in selective attention and monitoring. It detects conflicts between different sources of information and signals the need for cognitive control to resolve them. The ACC is also involved in the evaluation of the outcomes of attentional control and in the adjustment of behavior accordingly.
Top-down vs. bottom-up attentional systems and the brain structures that support them (dorsal frontoparietal network vs. right temporoparietal network).
Top-down attentional systems involve the voluntary allocation of attention based on goals and expectations, while bottom-up attentional systems are triggered by salient stimuli in the environment. The dorsal frontoparietal network, including the superior parietal lobule, intraparietal sulcus, and frontal eye fields, supports top-down attentional control. The right temporoparietal network, including the right temporoparietal junction and ventral frontal cortex, is involved in bottom-up attentional processes.
What are the main symptoms of hemineglect?
The main symptoms of hemineglect include a failure to attend to stimuli presented in the contralesional side of space, a lack of awareness of the deficit, and difficulty with daily activities that require attention to the neglected side.
What kind of brain damage is associated with hemineglect?
Hemineglect is most commonly associated with damage to the right parietal lobe, although it can also result from damage to other regions, such as the frontal lobes and subcortical structures.
What types of tasks are typically used to test the behavior of patients with hemineglect?
Tasks used to test the behavior of patients with hemineglect typically involve the detection or identification of stimuli presented on either side of space. Examples include line bisection tasks, cancellation tasks, and copying tasks.
What is anosagnosia?
Anosagnosia is a condition in which patients are unaware of their own deficits or impairments. It is commonly associated with damage to the right hemisphere, particularly in the parietal cortex.
What is simultagnosia?
What kind of damage is associated with it? Simultagnosia is a condition in which patients are unable to perceive more than one object at a time, even when multiple objects are present in their visual field. It is typically associated with damage to the bilateral parietal lobes, particularly in the dorsal visual stream.
SECTION 11
What do we mean by the term ‘executive function’?
Executive function refers to a set of cognitive processes that are involved in goal-directed behavior, including the ability to plan, organize, initiate, inhibit, and monitor behavior in response to changing demands.
What are the main anatomical divisions of the prefrontal cortex in humans?
The prefrontal cortex can be divided into three main regions: the dorsolateral prefrontal cortex, the ventromedial prefrontal cortex, and the orbitofrontal cortex.
What is the function of the orbitofrontal cortex?
The orbitofrontal cortex is involved in reward-based decision making, social cognition, and emotion regulation.
What did the case of Phineas Gage contribute to our understanding of the function of the orbitofrontal cortex?
The case of Phineas Gage, who suffered damage to his orbitofrontal cortex, provided evidence for the role of this region in social and emotional behavior.
What is perseveration? What do we define as utilization behavior (or environmental dependence)?
Perseveration refers to the tendency to continue a behavior or line of thought despite the absence or cessation of a reward. Utilization behavior, or environmental dependence, refers to the tendency to respond automatically to environmental stimuli, even when the response is not appropriate or desirable.
What are the consequences of medial prefrontal cortex damage?
Damage to the medial prefrontal cortex can result in deficits in social cognition, emotion regulation, and self-awareness.
What is the role of the dorsolateral prefrontal cortex (DLPFC) in working memory?
The DLPFC is involved in the active maintenance and manipulation of information in working memory.
What kinds of tasks allow us to measure working memory in humans?
Tasks that require the retention and manipulation of information over a short period of time, such as the n-back task or the digit span task, can be used to measure working memory in humans.
What kinds of tasks allow us to measure planning, decision-making, task shifting, and inhibition? What brain regions are associated with performance on these tasks?
Tasks such as the Tower of Hanoi, the Iowa Gambling Task, the Wisconsin Card Sorting Task, and the Stroop Task can be used to measure planning, decision-making, task shifting, and inhibition in humans. These tasks are associated with activity in the prefrontal cortex, particularly the DLPFC and the ventromedial prefrontal cortex.
What is the role of the anterior cingulate cortex (ACC) in error monitoring?
The ACC is involved in detecting and monitoring errors, and in adjusting behavior in response to errors.
SECTION 12
What is Broca's aphasia (or non-fluent aphasia) and what kind of brain injury is associated with it?
Broca's aphasia, also known as non-fluent aphasia, is a language disorder characterized by difficulties in producing language, particularly in speech production. Patients with Broca's aphasia may have difficulty speaking fluently, producing grammatically correct sentences, and finding the right words to express their thoughts. This type of aphasia is typically associated with damage to the left frontal cortex, particularly Broca's area.
What is Wernicke's aphasia (or fluent aphasia) and what kind of brain injury is associated with it?
Wernicke's aphasia, also known as fluent aphasia, is a language disorder characterized by difficulties in understanding language and producing meaningful speech. Patients with Wernicke's aphasia may produce fluent speech that is grammatically correct but lacks meaning or coherence. This type of aphasia is typically associated with damage to the left temporal cortex, particularly Wernicke's area.
What is global aphasia and what kind of brain injury is associated with it?
Global aphasia is a language disorder that affects all aspects of language, including comprehension, production, and repetition. Patients with global aphasia have difficulty understanding and producing speech, and they may also have difficulty reading and writing. This type of aphasia is typically associated with large left hemisphere lesions that involve both Broca's and Wernicke's areas.
What are the main tenets of the Wernicke-Geshwind model of aphasia?
The Wernicke-Geshwind model of aphasia proposes that language processing is supported by a network of brain regions, including Broca's area, Wernicke's area, and the arcuate fasciculus. According to this model, language comprehension begins in Wernicke's area, where words and their meanings are processed. Information is then transmitted via the arcuate fasciculus to Broca's area, where the motor program for speech production is generated.
What is the role of the arcuate fasciculus in language production and comprehension?
The arcuate fasciculus is a bundle of white matter fibers that connects Broca's area and Wernicke's area. It is thought to play a crucial role in language processing by facilitating the transmission of information between these two regions. Damage to the arcuate fasciculus can result in a variety of language disorders, including conduction aphasia, which is characterized by difficulty repeating words or sentences.
What are the main assumptions of the motor theory of language?
The motor theory of language proposes that language processing involves the same neural circuits that are involved in producing and perceiving action. According to this theory, the brain represents language in terms of the movements required to produce speech sounds. This motor representation is then used to recognize and understand spoken language.
Does damage to Broca's area cause Broca's aphasia?
Yes, damage to Broca's area is typically associated with Broca's aphasia, which is characterized by difficulties in producing language, particularly in speech production.
Does damage to Wernicke's area cause Wernicke's aphasia?
Yes, damage to Wernicke's area is typically associated with Wernicke's aphasia, which is characterized by difficulties in understanding language and producing meaningful speech.
What is Broca's aphasia (or non-fluent aphasia) and what kind of brain injury is associated with it?
Broca's aphasia, also known as non-fluent aphasia, is a language disorder characterized by difficulties in producing language, particularly in speech production. Patients with Broca's aphasia may have difficulty speaking fluently, producing grammatically correct sentences, and finding the right words to express their thoughts. This type of aphasia is typically associated with damage to the left frontal cortex, particularly Broca's area.
What is Wernicke's aphasia (or fluent aphasia) and what kind of brain injury is associated with it?
Wernicke's aphasia, also known as fluent aphasia, is a language disorder characterized by difficulties in understanding language and producing meaningful speech. Patients with Wernicke's aphasia may produce fluent speech that is grammatically correct but lacks meaning or coherence. This type of aphasia is typically associated with damage to the left temporal cortex, particularly Wernicke's area.
What is global aphasia and what kind of brain injury is associated with it?
Global aphasia is a language disorder that affects all aspects of language, including comprehension, production, and repetition. Patients with global aphasia have difficulty understanding and producing speech, and they may also have difficulty reading and writing. This type of aphasia is typically associated with large left hemisphere lesions that involve both Broca's and Wernicke's areas.
What are the main tenets of the Wernicke-Geshwind model of aphasia?
The Wernicke-Geshwind model of aphasia proposes that language processing is supported by a network of brain regions, including Broca's area, Wernicke's area, and the arcuate fasciculus. According to this model, language comprehension begins in Wernicke's area, where words and their meanings are processed. Information is then transmitted via the arcuate fasciculus to Broca's area, where the motor program for speech production is generated.
What is the role of the arcuate fasciculus in language production and comprehension?
The arcuate fasciculus is a bundle of white matter fibers that connects Broca's area and Wernicke's area. It is thought to play a crucial role in language processing by facilitating the transmission of information between these two regions. Damage to the arcuate fasciculus can result in a variety of language disorders, including conduction aphasia, which is characterized by difficulty repeating words or sentences.
What are the main assumptions of the motor theory of language?
The motor theory of language proposes that language processing involves the same neural circuits that are involved in producing and perceiving action. According to this theory, the brain represents language in terms of the movements required to produce speech sounds. This motor representation is then used to recognize and understand spoken language.
Does damage to Broca's area cause Broca's aphasia?
Yes, damage to Broca's area is typically associated with Broca's aphasia, which is characterized by difficulties in producing language, particularly in speech production.
Does damage to Wernicke's area cause Wernicke's aphasia?
Yes, damage to Wernicke's area is typically associated with Wernicke's aphasia, which is characterized by difficulties in understanding language and producing meaningful speech.
What are the differences between patients with left- and right-hemisphere lesions in terms of their performance on tasks that require global vs. local processing?
Answer: Patients with left-hemisphere lesions tend to perform better on tasks that require global processing, whereas patients with right-hemisphere lesions tend to perform better on tasks that require local processing. This suggests that the left hemisphere is specialized for processing global information, whereas the right hemisphere is specialized for processing local information.
What kind of evidence exists that would support a special role of the right hemisphere for spatial perception and face perception?
Answer: There is evidence that the right hemisphere is specialized for spatial perception and face perception. Patients with right-hemisphere lesions often have deficits in these areas, while patients with left-hemisphere lesions do not. Studies using functional neuroimaging techniques have also shown that specific areas in the right hemisphere are activated during tasks involving spatial perception and face perception.
What do patients with hemispherectomies reveal about the role of the left hemisphere in language?
Answer: Patients with hemispherectomies, in which one hemisphere of the brain is surgically removed, reveal that the left hemisphere plays a critical role in language. Patients who have undergone a left hemispherectomy typically have severe language deficits, whereas patients who have undergone a right hemispherectomy do not.
Michael Gazzaniga refers to the left hemisphere as ‘the interpreter.’ Why? Does the left hemisphere have a special role in making sense of our experiences?
Answer: Michael Gazzaniga refers to the left hemisphere as ‘the interpreter’ because he believes that it is responsible for creating a coherent narrative out of the experiences and sensations that we encounter. The left hemisphere may have a special role in making sense of our experiences because it is involved in language processing, which allows us to encode our experiences into a linguistic form. Additionally, the left hemisphere is involved in higher-order cognitive functions such as reasoning and problem-solving, which are necessary for making sense of complex experiences.
SECTION 9
What is the difference between learning and memory? (definitions)
Learning is the acquisition of new information or knowledge through experience, instruction, or study. Memory, on the other hand, refers to the ability to retain and retrieve information that has been learned or experienced in the past.
Main kinds of memory: declarative & non-declarative
Declarative memory refers to conscious memories that can be explicitly stated, such as facts and events. Non-declarative memory, also known as implicit memory, refers to unconscious memories that are expressed through performance, such as skills and habits.
What is the difference between long- and short-term memory?
Short-term memory is a temporary storage system for information that lasts for seconds to minutes, whereas long-term memory is a more permanent storage system for information that can last for days, months, or even a lifetime.
The case of H.M.: What kind of memory loss was he suffering from? What kind of brain damage led to his amnesia?
H.M. suffered from severe anterograde amnesia, which is the inability to form new long-term memories after the onset of amnesia. His amnesia was caused by surgical removal of the medial temporal lobes, including the hippocampus.
What kinds of memory systems are spared in cases of amnesia like H.M.’s? (be familiar with specific examples of tasks from the book and notes).
Memory systems that do not depend on the medial temporal lobes, such as procedural memory (e.g., learning how to ride a bike), are often spared in cases of amnesia like H.M.’s. For example, H.M. was able to improve his mirror-drawing skills over time despite not remembering practicing the task.
What is the difference between anterograde and retrograde amnesia?
Anterograde amnesia is the inability to form new long-term memories after the onset of amnesia, whereas retrograde amnesia is the loss of previously formed long-term memories, often for events that occurred before the onset of amnesia.
How can the damage to the medial diencephalon cause amnesia?
The medial diencephalon, which includes the thalamus and mammillary bodies, is connected to the medial temporal lobes and plays a crucial role in memory consolidation. Damage to the medial diencephalon can disrupt communication with the medial temporal lobes, leading to amnesia.
What kind of brain damage is observed in patients with Korsakoff’s syndrome? What type of memory deficits do these patients have?
Patients with Korsakoff’s syndrome often have damage to the medial diencephalon and frontal lobes, particularly the prefrontal cortex. They have severe anterograde amnesia and may also have retrograde amnesia, as well as confabulation (the production of false memories) and other cognitive deficits.
Can brain damage destroy autobiographical memories while sparing general memories?
Yes, brain damage can selectively impair autobiographical memories while leaving other types of memories relatively intact. For example, patients with damage to the ventromedial prefrontal cortex may have difficulty recalling personal experiences and emotions but have preserved general knowledge.
What is the difference between skill learning, priming, and conditioning?
Skill learning refers to the acquisition of new motor or cognitive skills through practice, such as playing a musical instrument. Priming refers to the facilitation of processing for a stimulus that has been previously encountered, such as reading a word more quickly the second time it appears. Conditioning refers to the learning of associations between stimuli or between a stimulus and a response, such as Pavlovian conditioning.
What is the difference between free recall, cued recall, and recognition memory?
Free recall is when a person is asked to remember information without any cues or prompts.
Cued recall is when a person is given a cue or prompt to help them remember the information.
Recognition memory is when a person is presented with a previously seen item among a set of novel items and asked to identify the previously seen item.
Does long-term memory have a limit? Is it perfectly accurate or is it subject to distortions? What kinds of distortions?
Long-term memory has a large but not infinite capacity, and it is not perfectly accurate. It is subject to various types of distortions such as forgetting, false memories, and source monitoring errors.
What brain mechanisms are involved in memory encoding, storage, and retrieval?
Memory encoding involves the consolidation of information from short-term memory to long-term memory, which is mediated by changes in synaptic strength and protein synthesis. Memory storage involves the maintenance of information in long-term memory, which is supported by the hippocampus and other cortical regions. Memory retrieval involves the activation of stored information, which is mediated by the prefrontal cortex and other brain regions.
What is semantic memory? How does it differ from episodic memory?
Semantic memory is a type of long-term memory that stores general knowledge about the world, including concepts, facts, and relationships between things. It differs from episodic memory, which stores personal experiences and events that have a specific time and place.
Is semantic memory affected in amnesia?
Semantic memory is generally spared in cases of amnesia, such as in the case of H.M. and other patients with medial temporal lobe damage.
What brain systems are presumed to support semantic memory?
The ventral and lateral regions of the prefrontal cortex, along with the anterior temporal lobe, are presumed to support semantic memory.
What does the term ‘memory consolidation’ refer to?
Memory consolidation refers to the process by which new memories are stabilized and strengthened in long-term memory over time, through changes in synaptic strength and protein synthesis. This process is thought to involve the hippocampus and other brain regions, and it is critical for the formation of enduring memories.
What is the difference between synaptic and system consolidation?
Synaptic consolidation refers to the process of strengthening the connections between neurons that are activated together during learning, while system consolidation refers to the process of transferring memories from the hippocampus to the neocortex, where they can be stored in a more stable and long-lasting form.
What is long-term potentiation? How does it relate to the function of the hippocampus?
Long-term potentiation (LTP) is a process of synaptic strengthening that occurs when two neurons are repeatedly activated together. LTP is thought to be a cellular mechanism that underlies learning and memory, and it has been extensively studied in the hippocampus, which is a brain region critical for learning and memory.
What kind of changes at the synaptic level support learning and memory?
Learning and memory are supported by changes in the strength and connectivity of synapses, which can be achieved through various mechanisms such as long-term potentiation (LTP), long-term depression (LTD), and structural changes in dendritic spines.
What is the function of medial temporal structures for declarative memory?
The medial temporal lobe (MTL) structures, including the hippocampus, parahippocampal cortex, and entorhinal cortex, are essential for the formation and retrieval of declarative memories, which are memories for facts and events that can be consciously recalled.
What is the contribution of hippocampal mechanisms to spatial memory?
The hippocampus plays a critical role in spatial memory, which is the ability to remember and navigate through an environment. Studies in rodents and humans have shown that the hippocampus is necessary for spatial learning and memory and that damage to the hippocampus impairs spatial navigation.
What brain structures support skill memory, repetition priming, and conditioning?
Skill memory is supported by the basal ganglia, a set of subcortical structures that are involved in motor control and learning. Repetition priming, which refers to the improved ability to identify a stimulus that has been previously encountered, is supported by the neocortex. Conditioning, which is the association of a stimulus with a particular outcome, is supported by the amygdala and other brain regions.
Summary graph: Brain regions involved in learning and memory
The summary graph shows that different brain regions are involved in different aspects of learning and memory, including the prefrontal cortex, basal ganglia, amygdala, hippocampus, and neocortex.
How do young and older adults differ in terms of their dependence on recall or recognition memory strategies? What kinds of brain structures differentially support these strategies?
Older adults tend to rely more on recognition memory than recall memory, whereas younger adults use both strategies equally. This difference may be related to changes in the prefrontal cortex, which is involved in executive control and working memory.
What is the main symptom of semantic dementia? What kind of brain damage is associated with the disorder?
The main symptom of semantic dementia is a progressive loss of semantic knowledge, which refers to the ability to understand and use words and concepts. This is associated with damage to the anterior temporal lobe, including the fusiform gyrus and temporal pole.
SECTION 10
What is the difference between attention and arousal?
Attention refers to the cognitive process of selectively attending to specific stimuli or features in the environment, while arousal refers to the physiological state of alertness and readiness to respond to stimuli.
What brain system is responsible for maintaining overall arousal levels?
The ascending reticular activating system (ARAS) in the brainstem is responsible for maintaining overall arousal levels.
What is the role of the cholinergic system in arousal and attention?
The cholinergic system, which involves the neurotransmitter acetylcholine, plays a role in both arousal and attention. It is involved in the maintenance of arousal and also in enhancing attentional processing.
What is the role of the noradrenergic system (in particular the locus coeruleus) to arousal?
The noradrenergic system, which involves the neurotransmitter norepinephrine, is involved in maintaining overall arousal levels, and in particular the locus coeruleus plays a key role in this process.
Structures of the thalamus critical for arousal
The intralaminar nuclei of the thalamus, including the centromedian nucleus, parafascicular nucleus, and central lateral nucleus, are critical for arousal.
What is the role of the thalamus in sustained attention?
The thalamus is involved in sustaining attention by relaying sensory information to the cortex and also by modulating activity in the cortex.
What is the difference between top-down (or endogenous) and bottom-up (or exogenous) attentional selection?
Top-down attentional selection refers to the deliberate allocation of attention based on prior knowledge, expectations, or goals, while bottom-up attentional selection refers to the automatic capture of attention by salient or novel stimuli in the environment.
What are the main tenets of early and late selection models of attention and what is the evidence in favor of each (specifically EEG & ERP evidence)?
Early selection models of attention propose that attentional selection occurs before sensory processing, while late selection models propose that selection occurs after sensory processing. EEG and ERP evidence supports both models, suggesting that the timing and extent of attentional selection may depend on task demands and stimulus characteristics.
What is the role of the superior colliculi in selective attention?
The superior colliculi play a role in selective attention by directing eye movements toward relevant stimuli in the environment.
What is the role of the thalamus in selective attention?
The thalamus is involved in selective attention by filtering sensory information based on attentional demands and modulating activity in the cortex.
Top-down attention modulation: The intraparietal sulcus
The intraparietal sulcus is involved in top-down attention modulation, particularly in the allocation of attention to spatial locations and the selection of relevant stimuli.
Is there a difference between the contributions of the left and right hemispheres in attention?
Yes, there is a difference in the contributions of the left and right hemispheres in attention. The left hemisphere is more specialized for attention to stimuli on the right side of the body or in the right visual field, whereas the right hemisphere is more specialized for attention to stimuli on the left side of the body or in the left visual field.
What is the role of the superior parietal lobe in selective attention?
The superior parietal lobe plays a critical role in selective attention by directing attention to specific locations in space. It integrates information from different sensory modalities and generates a spatial map that guides attention.
The anterior cingulate cortex and its role in selective attention and monitoring.
The anterior cingulate cortex (ACC) plays a key role in selective attention and monitoring. It detects conflicts between different sources of information and signals the need for cognitive control to resolve them. The ACC is also involved in the evaluation of the outcomes of attentional control and in the adjustment of behavior accordingly.
Top-down vs. bottom-up attentional systems and the brain structures that support them (dorsal frontoparietal network vs. right temporoparietal network).
Top-down attentional systems involve the voluntary allocation of attention based on goals and expectations, while bottom-up attentional systems are triggered by salient stimuli in the environment. The dorsal frontoparietal network, including the superior parietal lobule, intraparietal sulcus, and frontal eye fields, supports top-down attentional control. The right temporoparietal network, including the right temporoparietal junction and ventral frontal cortex, is involved in bottom-up attentional processes.
What are the main symptoms of hemineglect?
The main symptoms of hemineglect include a failure to attend to stimuli presented in the contralesional side of space, a lack of awareness of the deficit, and difficulty with daily activities that require attention to the neglected side.
What kind of brain damage is associated with hemineglect?
Hemineglect is most commonly associated with damage to the right parietal lobe, although it can also result from damage to other regions, such as the frontal lobes and subcortical structures.
What types of tasks are typically used to test the behavior of patients with hemineglect?
Tasks used to test the behavior of patients with hemineglect typically involve the detection or identification of stimuli presented on either side of space. Examples include line bisection tasks, cancellation tasks, and copying tasks.
What is anosagnosia?
Anosagnosia is a condition in which patients are unaware of their own deficits or impairments. It is commonly associated with damage to the right hemisphere, particularly in the parietal cortex.
What is simultagnosia?
What kind of damage is associated with it? Simultagnosia is a condition in which patients are unable to perceive more than one object at a time, even when multiple objects are present in their visual field. It is typically associated with damage to the bilateral parietal lobes, particularly in the dorsal visual stream.
SECTION 11
What do we mean by the term ‘executive function’?
Executive function refers to a set of cognitive processes that are involved in goal-directed behavior, including the ability to plan, organize, initiate, inhibit, and monitor behavior in response to changing demands.
What are the main anatomical divisions of the prefrontal cortex in humans?
The prefrontal cortex can be divided into three main regions: the dorsolateral prefrontal cortex, the ventromedial prefrontal cortex, and the orbitofrontal cortex.
What is the function of the orbitofrontal cortex?
The orbitofrontal cortex is involved in reward-based decision making, social cognition, and emotion regulation.
What did the case of Phineas Gage contribute to our understanding of the function of the orbitofrontal cortex?
The case of Phineas Gage, who suffered damage to his orbitofrontal cortex, provided evidence for the role of this region in social and emotional behavior.
What is perseveration? What do we define as utilization behavior (or environmental dependence)?
Perseveration refers to the tendency to continue a behavior or line of thought despite the absence or cessation of a reward. Utilization behavior, or environmental dependence, refers to the tendency to respond automatically to environmental stimuli, even when the response is not appropriate or desirable.
What are the consequences of medial prefrontal cortex damage?
Damage to the medial prefrontal cortex can result in deficits in social cognition, emotion regulation, and self-awareness.
What is the role of the dorsolateral prefrontal cortex (DLPFC) in working memory?
The DLPFC is involved in the active maintenance and manipulation of information in working memory.
What kinds of tasks allow us to measure working memory in humans?
Tasks that require the retention and manipulation of information over a short period of time, such as the n-back task or the digit span task, can be used to measure working memory in humans.
What kinds of tasks allow us to measure planning, decision-making, task shifting, and inhibition? What brain regions are associated with performance on these tasks?
Tasks such as the Tower of Hanoi, the Iowa Gambling Task, the Wisconsin Card Sorting Task, and the Stroop Task can be used to measure planning, decision-making, task shifting, and inhibition in humans. These tasks are associated with activity in the prefrontal cortex, particularly the DLPFC and the ventromedial prefrontal cortex.
What is the role of the anterior cingulate cortex (ACC) in error monitoring?
The ACC is involved in detecting and monitoring errors, and in adjusting behavior in response to errors.
SECTION 12
What is Broca's aphasia (or non-fluent aphasia) and what kind of brain injury is associated with it?
Broca's aphasia, also known as non-fluent aphasia, is a language disorder characterized by difficulties in producing language, particularly in speech production. Patients with Broca's aphasia may have difficulty speaking fluently, producing grammatically correct sentences, and finding the right words to express their thoughts. This type of aphasia is typically associated with damage to the left frontal cortex, particularly Broca's area.
What is Wernicke's aphasia (or fluent aphasia) and what kind of brain injury is associated with it?
Wernicke's aphasia, also known as fluent aphasia, is a language disorder characterized by difficulties in understanding language and producing meaningful speech. Patients with Wernicke's aphasia may produce fluent speech that is grammatically correct but lacks meaning or coherence. This type of aphasia is typically associated with damage to the left temporal cortex, particularly Wernicke's area.
What is global aphasia and what kind of brain injury is associated with it?
Global aphasia is a language disorder that affects all aspects of language, including comprehension, production, and repetition. Patients with global aphasia have difficulty understanding and producing speech, and they may also have difficulty reading and writing. This type of aphasia is typically associated with large left hemisphere lesions that involve both Broca's and Wernicke's areas.
What are the main tenets of the Wernicke-Geshwind model of aphasia?
The Wernicke-Geshwind model of aphasia proposes that language processing is supported by a network of brain regions, including Broca's area, Wernicke's area, and the arcuate fasciculus. According to this model, language comprehension begins in Wernicke's area, where words and their meanings are processed. Information is then transmitted via the arcuate fasciculus to Broca's area, where the motor program for speech production is generated.
What is the role of the arcuate fasciculus in language production and comprehension?
The arcuate fasciculus is a bundle of white matter fibers that connects Broca's area and Wernicke's area. It is thought to play a crucial role in language processing by facilitating the transmission of information between these two regions. Damage to the arcuate fasciculus can result in a variety of language disorders, including conduction aphasia, which is characterized by difficulty repeating words or sentences.
What are the main assumptions of the motor theory of language?
The motor theory of language proposes that language processing involves the same neural circuits that are involved in producing and perceiving action. According to this theory, the brain represents language in terms of the movements required to produce speech sounds. This motor representation is then used to recognize and understand spoken language.
Does damage to Broca's area cause Broca's aphasia?
Yes, damage to Broca's area is typically associated with Broca's aphasia, which is characterized by difficulties in producing language, particularly in speech production.
Does damage to Wernicke's area cause Wernicke's aphasia?
Yes, damage to Wernicke's area is typically associated with Wernicke's aphasia, which is characterized by difficulties in understanding language and producing meaningful speech.
What is Broca's aphasia (or non-fluent aphasia) and what kind of brain injury is associated with it?
Broca's aphasia, also known as non-fluent aphasia, is a language disorder characterized by difficulties in producing language, particularly in speech production. Patients with Broca's aphasia may have difficulty speaking fluently, producing grammatically correct sentences, and finding the right words to express their thoughts. This type of aphasia is typically associated with damage to the left frontal cortex, particularly Broca's area.
What is Wernicke's aphasia (or fluent aphasia) and what kind of brain injury is associated with it?
Wernicke's aphasia, also known as fluent aphasia, is a language disorder characterized by difficulties in understanding language and producing meaningful speech. Patients with Wernicke's aphasia may produce fluent speech that is grammatically correct but lacks meaning or coherence. This type of aphasia is typically associated with damage to the left temporal cortex, particularly Wernicke's area.
What is global aphasia and what kind of brain injury is associated with it?
Global aphasia is a language disorder that affects all aspects of language, including comprehension, production, and repetition. Patients with global aphasia have difficulty understanding and producing speech, and they may also have difficulty reading and writing. This type of aphasia is typically associated with large left hemisphere lesions that involve both Broca's and Wernicke's areas.
What are the main tenets of the Wernicke-Geshwind model of aphasia?
The Wernicke-Geshwind model of aphasia proposes that language processing is supported by a network of brain regions, including Broca's area, Wernicke's area, and the arcuate fasciculus. According to this model, language comprehension begins in Wernicke's area, where words and their meanings are processed. Information is then transmitted via the arcuate fasciculus to Broca's area, where the motor program for speech production is generated.
What is the role of the arcuate fasciculus in language production and comprehension?
The arcuate fasciculus is a bundle of white matter fibers that connects Broca's area and Wernicke's area. It is thought to play a crucial role in language processing by facilitating the transmission of information between these two regions. Damage to the arcuate fasciculus can result in a variety of language disorders, including conduction aphasia, which is characterized by difficulty repeating words or sentences.
What are the main assumptions of the motor theory of language?
The motor theory of language proposes that language processing involves the same neural circuits that are involved in producing and perceiving action. According to this theory, the brain represents language in terms of the movements required to produce speech sounds. This motor representation is then used to recognize and understand spoken language.
Does damage to Broca's area cause Broca's aphasia?
Yes, damage to Broca's area is typically associated with Broca's aphasia, which is characterized by difficulties in producing language, particularly in speech production.
Does damage to Wernicke's area cause Wernicke's aphasia?
Yes, damage to Wernicke's area is typically associated with Wernicke's aphasia, which is characterized by difficulties in understanding language and producing meaningful speech.
What are the differences between patients with left- and right-hemisphere lesions in terms of their performance on tasks that require global vs. local processing?
Answer: Patients with left-hemisphere lesions tend to perform better on tasks that require global processing, whereas patients with right-hemisphere lesions tend to perform better on tasks that require local processing. This suggests that the left hemisphere is specialized for processing global information, whereas the right hemisphere is specialized for processing local information.
What kind of evidence exists that would support a special role of the right hemisphere for spatial perception and face perception?
Answer: There is evidence that the right hemisphere is specialized for spatial perception and face perception. Patients with right-hemisphere lesions often have deficits in these areas, while patients with left-hemisphere lesions do not. Studies using functional neuroimaging techniques have also shown that specific areas in the right hemisphere are activated during tasks involving spatial perception and face perception.
What do patients with hemispherectomies reveal about the role of the left hemisphere in language?
Answer: Patients with hemispherectomies, in which one hemisphere of the brain is surgically removed, reveal that the left hemisphere plays a critical role in language. Patients who have undergone a left hemispherectomy typically have severe language deficits, whereas patients who have undergone a right hemispherectomy do not.
Michael Gazzaniga refers to the left hemisphere as ‘the interpreter.’ Why? Does the left hemisphere have a special role in making sense of our experiences?
Answer: Michael Gazzaniga refers to the left hemisphere as ‘the interpreter’ because he believes that it is responsible for creating a coherent narrative out of the experiences and sensations that we encounter. The left hemisphere may have a special role in making sense of our experiences because it is involved in language processing, which allows us to encode our experiences into a linguistic form. Additionally, the left hemisphere is involved in higher-order cognitive functions such as reasoning and problem-solving, which are necessary for making sense of complex experiences.
