Lecture 21 - Cerebral cortex and diencephalon Flashcards
Gray Matter
Sheet of neural tissue that makes up outer layer of the brain
White Matter
Nerve fibers that connect neurons in different brain regions into functional circuits
Sulci and Gyri
Increase cortical surface area
10 functions of the cortex
- Memory storage and recall
- Language comprehension/production
- Musical abilities
- Attention
- Process all sensations
- Object and face recognition
- Plan/execute motor activities
- Integrate prior experiences
- Emotions
- Pain and threat detection
Name the 4 lobes of the brain
- Frontal
- Parietal
- Occipital
- Temporal
Name the 6 key areas of the frontal lobe
- Primary motor area (4)
- Premotor Area (6)
- Supplementary Motor Area (6)
- Frontal Eye Fields (8)
- Brocas Area
- Prefrontal Area
Name 4 primary frontal lobe functions and describe them
- Movement Control: Planning and execution of movements
- Conjugate Eye Movements: Moving eyes together (R frontal eye controls movement of both eyes to left)
- Speech production (Broca’s area): Process info of temporal cortex and writes a script for speech that is passed to primary motor cortex
- Personality: Damage causes hypo-emotionality, disturbed social behaviour, distress, emotional dysregulation, and decision making
What 5 affects happen due to frontal lobe lesions
- Hemiplegia
- Weakness
- Apraxia
- Personality Disorders
- Aphasia
Apraxia
Unable to perform learned movements on command
Hemiplegia
Paralysis to one side of the body
Aphasia
Deficits in language expression
Parietal lobe 3 key areas
- Primary Somatosensory (1,2,3,deeper aspect of 4)
- Secondary Somatosensory (5,40)
- Association areas (7,39)S
Name and describe the 2 primary functions of the parietal lobe
- Sensation: Receives sensory inputs from thalamus and is responsible for touch, position, vibration, pressure, and temperature
- Integrate sensory info with other modalities of higher functions such as motor planning, learning, language, spatial recognition and stereognosis
Stereognosis
Ability to differentiate between objects based on size, shape, weight
What 4 factors occur due to parietal lobe lesions
- Loss of sensation
- Sensory Apraxia
- Asomatognosia
- Neglect Syndrome
Sensory Apraxia
Unable to use an object because an individual cannot perceive its purpose
Asomatognosia
Denial of existence of a body part
Neglect Syndrome
Failure to recognize opposite side of body and its surroundings
Occipital Lobe 2 key areas
1) Primary Visual area (17)
2. Visual Association Area (18,19)
Occipital lobe function
Visual processing and interpretation
What 3 factors occur due to occipital lobe lesions
- Blindness
- Color blindness
- Inability to detect moving objects
Temporal lobe 6 key areas
- Primary auditory area (41)
- Secondary Auditory Area (42)
- Auditory Association Area (22)
- Areas associated with emotion
- Memory
- Speech- Wernicke’s Area (22)
Name the 7 functions of the temporal lobe
- Translating/processing all sounds and tones
- Phonological representation of words
- Semantic retrieval
- Semantic memory
- Visual/Facial perception
- Declarative Memory
- Familiarity
Semantic Retrieval
Assign meaning to words
Semantic Memory
Remembering thoughts/objectives that are common knowledge
Declarative Memory
Remembering concepts/events that happened or learned throughout life
What are 6 affects due to temporal lobe lesions
- Phenomics paraphasia
- Memory impairments/forgetfulness
- Visual hallucinations
- Inability to recognize faces/self
- Impaired language comprehension
- Unilateral lesion will affect localization of sound but not produce significant hearing loss
Phenomics paraphasia
Sound substitution/rearrangement (tephelone instead of telephone
What are the 4 key regions of the diencephalon
- Thalamus
- Hypothalamus
- Epithalamus
- Subthalamus
Thalamus
2 oval collections of nuclei that process all sensory info (except smell) before being sent to cortex
What are the 4 nuclei that make up the thalamus and their function
- Medial Geniculate Nuclei -> hearing
- Lateral Geniculate Nuclei -> vision
- Ventral Posterior Nuclei -> taste and somatic sensations (pressure)
- Anterior Nucleus -> emotions and memory
6 functions of the diencephalon
Primary relay and processing center for sensory info and autonomic control:
1. Control autonomic body functions
2. Connect endocrine structures
3. Limbic system
4. Motor function
5. Hearing, vision, smell, taste
6. Touch perception
10 affects of a diencephalon lesion
- Memory loss
- Lack of interest
- Trouble with attention/alertness
- Impaired movement
- Trouble processing sensory info
- Sleeping/unconsciousness
- Insomnia
- Thalamic aphasia (jumbled words/meaningless speech)
- Vision problems
- Thalamic pain syndrome (tingling/burning pain)
What are the 4 fibers for cortical communication
- Intracortical fibers
- Association fibers
- Commissural fibers
- Projection fibers
Intracortical fibers
Connect neurons in localized area
Association fibers
Connect between gyri and from lobe to lobe in same hemisphere eg. superior longitudinal fasciculus
Commissural Fibers
Connect homologous areas of 2 hemispheres eg. corpus callosum
Projection fibers
Connect cortex with subcortical nuclei
Name 2 projection fibers and if they are afferent or efferent
- Corticofugal (efferent)
- Corticopetal (afferent)
T or F: Some functions are lateralized to one hemisphere (eg. motor skills) resulting in higher functions on that one side
T
T or F: Everyones brain is the same
F
Neuroplasticity
Ability of nervous system to rewire
List 2 factors affected by neuroplasticity
- Learning and memory
- Recovery of function after injury
[blank] input is the most powerful driver of plasticity
Afferent
What is the diagnosis, any symptoms that through us off, and how to manage through physiotherapy
Diagnosis: Frontal lobe syndrome and xray/CT scan show multiple fontal bone fracture and edema
Symptoms that throw off: Sensory system issues like sensorimotor integration and anosmia; speech issues as all these areas are located in frontal cortex
Physiotherapy: Target exercise for grip strength, exercise focused on balance/coordination, active rehab for neuroplasticity, manage expectations/behavioral symptoms, and appropriate short/long-term planning with family
