Concussions, TBIs, and strokes tend to affect multiple regions of the brain and nervous system, so it can be helpful to understand a bit about the varying functions of different brain regions during your recovery process. The human central nervous system (CNS) consists of the brain and the spinal cord. In this article, we will be providing a brief overview of the brain and its different regions. Please note that we will go into further detail for each region in future articles, as well as the brain stem and spinal cord, so this will serve as a solid foundation as you navigate your unique brain injury.
The brain is an amazing, complex organ, so we reiterate again that this is a brief overview of the different regions, their functions, and signs of damage. Please also note that the different regions of the brain function together through networks of interconnectivity in order to complete tasks. In other words, while movement may be initiated in the frontal lobe, it also requires activity from other parts of the brain such as the cerebellum and basal ganglia. Keeping this in mind will help to avoid any confusion if a function is listed under multiple different brain regions.
The Frontal Lobe: Executive Function, Movement, Higher Thinking
- Executive Function/Decision Making
- Speech and language production
- Broca’s area, a region in the frontal lobe, helps put thoughts into words. Damage to this area can lead to difficulty with fluent speech.
- Voluntary motor actions (movement):
- The frontal lobe houses the primary motor cortex, which helps control voluntary movements, including walking and running.
- Comparing objects:
- The frontal lobe helps people categorize and classify objects and distinguish one item from another.
- Understanding and reacting to the feelings of others:
- The frontal lobe is vital for empathy.
- Forming personality:
- The complex interplay of impulse control, memory, and other tasks helps form an individual’s key characteristics.
- Damage to the frontal lobe can impact an individual’s personality.
- Reward-seeking behavior and motivation:
- Many of the brain’s dopamine-sensitive neurons are in the frontal lobe. Dopamine is a brain chemical that helps support feelings of reward and motivation.
- Managing attention, including selective attention:
The Temporal Lobe: Sensory Processing, Memory, Language, and Emotional Regulation
1. Auditory Processing
- Primary auditory cortex (located in the superior temporal gyrus) processes sound information.
- Distinguishes pitch, volume, and tone.
- Recognizes and interprets speech and other sounds.
- Aids in auditory memory (e.g., remembering melodies or voices).
2. Language Comprehension
- Wernicke’s Area (in the left temporal lobe) is crucial for understanding spoken and written language.
- Damage to this area can result in Wernicke’s aphasia, where speech remains fluent but lacks meaning.
- Plays a role in processing semantics and the meaning of words.
3. Memory Formation and Retrieval
- The hippocampus, located within the medial temporal lobe, is critical for forming new long-term memories.
- Converts short-term memories into long-term storage.
- Involved in episodic memory (memory of personal experiences) and declarative memory (facts and knowledge).
- Damage to the hippocampus can result in anterograde amnesia (inability to form new memories).
4. Emotion and Social Behavior
- The amygdala, located in the medial temporal lobe, processes emotions, particularly fear and pleasure.
- Involved in emotional memory, such as associating experiences with positive or negative feelings.
- Plays a role in recognizing facial expressions and social cues.
- Helps regulate responses to stress and threats (fight-or-flight response).
5. Multisensory Integration
- Integrates information from hearing, vision, and smell to create a coherent perception of the environment.
- Helps in forming associations between sensory inputs (e.g., recognizing a song and linking it to a memory).
6. Spatial Navigation and Orientation
- Works with the hippocampus to process spatial memory, such as remembering locations or navigating environments.
- Supports the ability to mentally visualize spatial relationships.
7. Processing of Time and Sequence
- Involved in perceiving temporal aspects of sounds and speech.
- Helps track the order of events and predict future outcomes based on past experiences.
8. Higher-Level Cognitive Functions
- Supports semantic memory, which allows for understanding concepts and categories.
- Contributes to abstract thinking and reasoning.
- Involved in creativity and the processing of music and artistic expression.
The Parietal Lobe: Spatial Awareness, Sensory Processing, Cognition
1. Somatosensory Processing (Touch, Temperature, Pain)
- The primary somatosensory cortex (in the postcentral gyrus) processes sensations from the skin and muscles.
- Detects touch, pressure, pain, temperature, and proprioception (body position in space).
- Differentiates textures, shapes, and weights of objects.
2. Spatial Awareness and Navigation
- Helps perceive distances, depth, and object locations.
- Allows the brain to mentally map surroundings, aiding in navigation.
- Involved in spatial reasoning and understanding object relationships in space.
3. Motor Coordination and Movement Planning
- Works with the frontal lobe to guide voluntary movements.
- Assists in hand-eye coordination and fine motor skills.
- Plays a role in sensorimotor integration, linking sensory input with motor actions.
4. Body Awareness (Proprioception)
- Helps in knowing where body parts are without looking.
- Assists in balance and coordinated movement.
5. Mathematical and Logical Thinking
- Involved in numerical processing, calculations, and estimating quantities.
- Supports logical reasoning and problem-solving.
6. Language and Reading Comprehension
- In the dominant hemisphere (usually left), contributes to reading, writing, and language comprehension.
- The angular gyrus is involved in interpreting written words and connecting them to spoken language.
- Damage to this area can cause dyslexia, agraphia (writing difficulties), or alexia (inability to read).
7. Attention and Perception
- Helps direct attention to different parts of the environment.
- Plays a role in visual perception and tracking objects in motion.
- The right parietal lobe is crucial for awareness of the left side of space (damage can lead to hemispatial neglect).
8. Integration of Sensory Information
- Combines input from multiple senses to create a coherent understanding of the environment.
- Aids in object recognition by linking touch, vision, and spatial awareness.
9. Imagery and Mental Rotation
- Helps visualize and mentally manipulate objects.
- Important for tasks requiring mental rotation (e.g., imagining how an object would look from different angles).
10. Reflexive and Automatic Responses
- Works with other brain regions to help with reflexive movements, such as pulling away from a painful stimulus.
- Assists in subconscious adjustments to posture and movement.
The Occipital Lobe: Visual Processing
1. Primary Visual Processing
- The primary visual cortex (V1), also known as the striate cortex, processes raw visual data from the retina.
- Receives input from the optic nerve via the thalamus (specifically, the lateral geniculate nucleus).
- Interprets basic visual attributes such as brightness, contrast, and orientation.
2. Visual Perception and Interpretation
- Recognizes shapes, colors, and motion.
- Helps in object identification and differentiation.
- Processes depth perception and spatial relationships.
3. Motion Detection and Tracking
- Certain areas of the occipital lobe, like V5/MT, specialize in detecting movement and speed of objects.
- Helps the brain distinguish between stationary and moving objects.
4. Color Perception
- The V4 region in the occipital lobe is responsible for color processing.
- Damage to this area can result in achromatopsia (color blindness).
5. Visual Memory and Recognition
- Works with the temporal lobe to recognize faces, places, and objects.
- Helps in visual learning and recall.
6. Reading and Visual Processing of Text
- Assists the parietal and temporal lobes in interpreting written language.
- Plays a role in letter recognition and reading comprehension.
7. Visual Attention and Focus
- Works with the parietal lobe to determine what visual information is important.
- Helps the brain filter out irrelevant visual stimuli.
8. Visual-Spatial Orientation
- Helps process the position of objects in relation to oneself.
- Works with the parietal lobe for hand-eye coordination.
9. Processing of Visual Illusions
- Interprets complex visual patterns and illusions.
- Helps distinguish between reality and optical distortions.
10. Coordination with Other Brain Regions
- Communicates with the temporal lobe for object and face recognition.
- Works with the parietal lobe for spatial awareness.
- Sends processed visual information to higher brain areas for decision-making and action.
The Cerebellum: Movement Coordination, Balance, Fine Motor Control
1. Coordination of Voluntary Movements
- Ensures smooth, precise, and coordinated movements.
- Works with the motor cortex and basal ganglia to fine-tune motor activity.
- Helps control timing and accuracy of movements.
2. Balance and Postural Control
- Maintains equilibrium and posture by processing input from the vestibular system (inner ear).
- Adjusts body position to prevent falls and maintain stability.
3. Motor Learning and Muscle Memory
- Plays a key role in learning new motor skills, such as playing an instrument or riding a bike.
- Stores procedural memory for repetitive, learned movements.
4. Fine Motor Control and Precision
- Regulates small, precise movements, such as handwriting or playing the piano.
- Helps in grasping and manipulating objects with dexterity.
5. Eye Movement Control
- Coordinates smooth pursuit and saccadic (rapid) eye movements.
- Works with the vestibular system to maintain gaze stability during head movements.
6. Speech Coordination
- Helps regulate speech articulation and rhythm.
- Damage can lead to dysarthria (slurred or uncoordinated speech).
7. Timing and Predictive Movement
- Assists in predicting movement timing (e.g., catching a ball).
- Helps anticipate body adjustments needed for smooth motion.
8. Cognitive Functions and Attention
- Plays a role in attention, problem-solving, and working memory.
- Involved in decision-making and emotional regulation (via connections with the prefrontal cortex).
9. Error Detection and Correction
- Constantly compares intended movements with actual execution.
- Makes real-time adjustments to refine accuracy.
