Neuroanatomy|Brain Flashcards
How much does the human brain weigh?
2.8 to 3 lbs
The cerebrum comprises what percentage of total brain weight?
85%
60% of the brain’s total weight is comprised of what?
Fat
The brain uses what percentage of our oxygen?
20%
The brain uses what percentage of our glucose?
25%
How many minutes of oxygen loss leads to brain damage?
5-10 minutes
What cranial landmark is located at the base of the skull at the external occipital protuberance?
Inion
How many watts of power does the electrical activity of the brain generate?
30
The autonomic nervous system is comprised of what two systems?
Sympathetic and parasympathetic nervous systems
What is the difference between the parasympathetic and sympathetic nervous systems?
Parasympathetic controls “rest and digest”; sympathetic controls “fight-or-flight”
What nervous system is responsible for “rest and digest”?
Parasympathetic
What nervous system is responsible for “fight-or-flight”?
Sympathetic
What does functional connectivity refer to?
The intact relationship between various, somewhat discreet, functional areas of the brain
What does effective connectivity refer to?
Attempts to identify the nature and direction of information flow across brain networks
The outermost layer of the cerebral cortex is comprised of what?
Gray matter
What structure divides the hemispheres of the brain?
Corpus collosum
What are the fissures within the cerebral cortex called?
Sulci
What functions are normally associated with the left hemisphere?
IQ, intellectual encoding, logical processing, verbal expression, memory, auditory, math, grammar, problem solving, word recognition
What functions are associated with the right hemisphere?
Social encoding, emotional process, non-verbal expression, music, auditory, special problem solving, face recognition, empathy, early self-concept
What functions are normally associated with the anterior brain?
Attention and executive planning
What functions are associated with the midline?
Impulse control
What functions are associated with the central sulcus area?
Sensory/motor functions & Mood stability
In what lobe does verbal and non-verbal association take place?
Parietal
What is the most prominent part of the brain?
Cerebrum, divided into right and left hemispheres. Outer layer is cerebral cortex responsible for higher mental functions. It’s about 1/8” thick. Divided into 4 lobes.
How are the lobes of the brain named?
In conjunction with the cranial bones above it
What lobe’s key functions include math, naming objects, complex grammar, spatial awareness, and recognizing oneself as distinct from the outside world?
Parietal lobe
What lobe’s key functions include verbal memories, word recognition, reading, language, emotion (left hemisphere) and music, facial recognition, social cues, object recognition (right hemisphere)?
Temporal lobe
What lobe is most related to the visual field?
Occipital lobe
What part of the brain is associated with conscious control of all skeletal muscle movements?
Sensorimotor cortex
Broca’s area is specifically related to what neurological function?
Formulation of speech
Wernicke’s area is specifically related to what neurological function?
Comprehension of language
What is the key function of the somatosensory cortex?
Spatial discrimination, ability to identify where body sensations originate
What structure exists along the Z-line (Fpz, Fz, Cz, Pz)?
Cingulate gyrus
What functions are associated with the anterior cingulate gyrus?
Cognitive control; conflict monitoring and resolution; emotional regulation; pain and reward processing; adaptive learning; social and moral decision-making.
Anterior cingulate is associated with mental flexibility, cooperation, attention. It helps the mind let go of problems and concerns, shift gears and make transitions, stop ritualistic movements and tics. Cingulate oversees motivation, social self and personality. It’s closely aligned with the amygdala. A “hot” cingulate means it’s overactive and causing problems.
How many layers of cells comprise the cortex?
Six
What type of cell outnumber all other cell types and is most responsible for the generation of pre- and post-synaptic potentials in the EGG?
Pyramidal
Stellate cells, or interneurons, that facilitate communication between pyramidal cells exist mainly in what layer of the cortex?
Layer 4
What are the pyramidal nerve tracts?
Ascending and descending pathways that range from the spinal cord to the lower brain without synaptic interruption. They don’t extend directly into the cerebral cortex.
What is the function of extrapyramidal cells?
They comprise all remaining motor components within the cerebral cortex. They also connect the cortex with other brain structures like the basal ganglia, cerebellum, reticular formation and the thalamus.
What functions are associated with the posterior cingulate gyrus?
(Primary) Maintaining Default Mode Network (DMN); also: memory retrieval; spatial orientation and navigation; emotional processing; somewhat related to attention and task-related activities
The posterior cingulate gyrus is part of what anatomical system?
The limbic system
Is the anterior cingulate gyrus part of the limbic system?
The anterior cingulate gyrus (ACC) is often considered a transitional region between the limbic system and the frontal cortex. While it is not traditionally classified as part of the core limbic system, it has significant functional and anatomical connections with both limbic and frontal cortical regions. As a result, the ACC plays a vital role in mediating between emotional and cognitive processes.
The cingulate gyrus is located along and superior to what structure of the brain?
The corpus collosum
What four subcortical structures comprise the limbic system (seat of emotion)?
Hippocampus
Amygdala
Thalamus
Hypothalamus
What two things does the limbic system process?
Emotional Information and Memory
What subcortical structure is associated with explicit memory?
Hippocampus
What is explicit memory?
Explicit memory, also known as declarative memory, is a type of long-term memory that involves the conscious, intentional recollection of facts, events, and information. It refers to the ability to consciously retrieve specific details or knowledge about past experiences. Explicit memory is characterized by the conscious awareness of what is being remembered, and it can be further divided into two subtypes: Semantic memory and Episodic memory.
Explicit memory is also known as what?
Declarative memory
What are the two subtypes of explicit memory?
Semantic and Episodic
What is semantic memory?
FACTUAL MEMORY
Semantic memory is a subtype of explicit memory that relates to general knowledge and facts about the world. It includes information such as language, concepts, facts, and general knowledge that is not tied to a specific personal experience. For example, knowing that Paris is the capital of France or that water boils at 100 degrees Celsius is a form of semantic memory.
What is episodic memory?
PERSONAL MEMORIES OF ONE’S PAST
Episodic memory is a subtype of explicit memory that pertains to personal experiences and events that occurred at specific times and places. It involves recalling autobiographical details, such as your first day of school, a family vacation, or a birthday party. Episodic memories are tied to the context in which they occurred and are often characterized by a sense of time and place.
What subcortical structure is associated with implicit memory?
Amygdala
What is implicit memory?
Unconscious, long-term memory that influences current thought, behavior, and performance.
Implicit memory is thought to rely on different neural pathways and structures compared to explicit memory. The basal ganglia, cerebellum, and various regions of the neocortex are involved in the formation and expression of implicit memories.
One of the intriguing aspects of implicit memory is that it often persists even in cases of amnesia or damage to explicit memory systems, such as the hippocampus. This highlights the distinct nature of implicit memory and its importance in our daily lives, as it guides our actions, habits, and responses without our conscious awareness.
What subcortical structure is considered the heart of the brain?
Thalamus
What structure serves as editor for sorting and directing sensory information and emotions, influencing brainwaves through connections with the cortex?
Thalamus
What is the largest job of the hippocampus?
Transfer short-term memories to long-term storage
What is the function of the hypothalamus?
Control body temperature, hunger, fatigue, sleep (neuroendocrine events and autonomic nervous system)
What subcortical structure controls the autonomic components of emotion (e.g., heart rate, blood pressure, respiration)?
Amygdala
Where is the amygdala located?
Medial temporal lobe, anterior to the hippocampus.
The amygdala is a pair of almond-shaped clusters of nuclei located deep within the brain, one on each side. They are situated in the medial temporal lobe of the brain, which is near the base of the brain and is involved in various aspects of emotional processing and memory. Specifically, the amygdala is positioned anterior to the hippocampus, another important structure for memory, and is part of the limbic system, which plays a central role in emotions and emotional responses. The amygdala is highly interconnected with other brain regions and is known for its critical role in processing and regulating emotions, particularly fear and emotional memory.
Where is the hippocampus located?
Medial temporal lobe, adjacent to the lateral ventricles.
The hippocampus is a seahorse-shaped structure located deep within the brain, in the medial temporal lobe. It is situated in both hemispheres of the brain, with one hippocampus in the left hemisphere and another in the right hemisphere. The hippocampus is positioned adjacent to the lateral ventricles, which are fluid-filled spaces within the brain.
Damage to the hippocampus could result in what types of problems?
Significant memory deficits, such as anterograde amnesia (the inability to form new memories) and difficulties in spatial orientation.
Where is the thalamus located?
The thalamus is a vital structure in the brain located at the center of the brain, deep within the cerebral hemispheres. It is part of the diencephalon, which is the central portion of the brain. The thalamus consists of two small, symmetrical structures, one in each hemisphere of the brain.
What subcortical structure acts as a sensory gateway, receiving sensory input from various sensory systems (e.g., vision, hearing, touch, taste, and smell) and then transmitting this information to the appropriate regions of the cerebral cortex, where further processing and perception occur?
Thalamus
Where is the hypothalamus located?
The hypothalamus is a small but vital region of the brain located near the base of the brain, just above the brainstem and below the thalamus. It is a central structure within the diencephalon, which is a subdivision of the brain’s forebrain.
What is the diencephalon?
The diencephalon is a distinct and crucial part of the brain located in the forebrain, specifically in the central core of the brain between the cerebral hemispheres and above the brainstem. It consists of several important structures, including the thalamus, hypothalamus, epithalamus, and subthalamus.
What is the function of the structures that comprise the diencephalon?
It serves as a bridge between the brainstem and the cerebral hemispheres, facilitating communication between different parts of the brain and helping to coordinate and control various bodily functions. The diencephalon acts as a relay and integration center for various sensory and motor pathways and plays a critical role in regulating many physiological processes essential for survival.
Where is the reticular formation located?
Within the brainstem
What is the function of the reticular formation and reticular activation system (RAS)?
To relay impulses from the brainstem to the cortex, hippocampus, and thalamus. Plays a significant role in attention and maintaining sleep/wake cycles.
What brain structure has the primary function of controlling body movements, coordination, and posture?
Cerebellum
What is the function of the medulla?
Regulating essential autonomic and involuntary functions that are critical for survival (e.g., cardiovascular control, respiration, swallowing, vital reflexes, sleep)
Where is the medulla located?
The medulla, also known as the medulla oblongata, is a crucial part of the brainstem located just above the spinal cord and below the pons.
What is the function of the brainstem?
Connect the spinal cord to the brain
What parts comprise the brainstem?
Medulla
Pons
Midbrain
Reticular formation
Cranial nerve nuclei
What structure is the lowermost part of the brainstem?
Medulla
Where is the pons located?
In the brainstem, just above the medulla and below the midbrain
What part of the brain connects the cerebellum to the cerebral cortex and contains the cranial nerves of the face?
Pons
What subcortical structure sits atop the brainstem?
Thalamus
What subcortical structure sends signals from the Reticular Activation System (RAS) to various areas of the cerebral cortex?
Thalamus
The amygdala has strong connections with what lobe of the brain?
Frontal
What subcortical structure is most related to issues of memory?
Hippocampus
What subcortical structure is most related to emotion?
Amygdala
What subcortical structure is considered the perceptual gateway to the brain?
Thalamus
What region of the brain controls motor movement and interfaces heavily with the cerebellum to execute learned sequences of motor action, such as playing a piece of music?
Basal ganglia or Stratium
What is the function of the basal ganglia?
The control of voluntary motor movements, but it also plays a role in various cognitive and emotional functions.
Where is the basal ganglia located?
Near the base of the forebrain
The forebrain is also known as what latin term?
Prosencephalon
The forebrain (prosencephalon) is divided into what two main regions?
The telencephalon and diencephalon.
What is the telencephalon?
The telencephalon is the most anterior part of the forebrain and includes the cerebral hemispheres, which make up the bulk of the brain. The cerebral hemispheres are further divided into the left and right hemispheres and are responsible for higher cognitive functions, such as thinking, memory, perception, and voluntary motor control. The telencephalon also contains the basal ganglia, olfactory bulbs, and other structures.
How many cranial nerves are there?
12
What cranial nerve is the olfactory nerve?
CN I (1) - smell
What cranial nerve is the optic nerve?
CN II (2) - visual perception
What cranial nerve is the oculomotor nerve?
CN III (3) - eye movement and pupil constriction
What cranial nerve is the trochlear nerve?
CN IV (4) - downward/inward eye movements
What cranial nerve is the trigeminal nerve?
CN V (5) - face sensation and chewing
What cranial nerve is the abducens nerve?
CN VI (6) - outward eye movement
What cranial nerve is the facial nerve?
CN VII (7) - facial expressions, taste on the anterior 2/3 of the tongue, salivation and tear glands
What cranial nerve is the vestibulocochlear nerve?
CN VIII (8) - hearing and balance (inner ear)
What cranial nerve is the glossopharyngeal nerve?
CN IX (9) - taste from posterior 1/3 of tongue, swallowing, blood pressure
What cranial nerve is the vagus nerve?
CN X (10) - wide autonomic functions
What cranial nerve is the accessory nerve?
CN XI (11) - head and shoulder movement
What cranial nerve is the hypoglossal nerve?
CN XII (12) - tongue muscles, swallowing, speech
What percentage of the brain’s total neurons are in the cerebrum (cerebral cortex)?
19%
All sensory information coming into the body goes through the ventral nuclei of the _____ and into the somatosensory regions of the cortex.
Thalamus
The _____ appears to engage and disengage different areas of the cortex through a resonance process involving the use of ______ as a form of braking.
thalamus; alpha
What frequency does the thalamus clearly employ in a gating system to control information flowing to and from sections of the cortex controlling primary motor functions?
SMR
What percent of the measured EEG is considered local, with the remaining percentage coming from volume conduction?
60%
What is the primary frequency generated by the cerebrum?
Beta
What is the primary frequency generated by the limbic system?
Theta
What is the primary frequency associated with the brain stem and cerebellum?
Delta
What is the primary frequency associated with the thalamus?
Alpha
