BBB AP Psychology

Brain Structures, Lobes, and Plasticity

Hindbrain

• Cerebellum

  • Coordinates fine muscle movement and balance

  • Key role in organizing sensory information

  • Processes nonverbal learning and memory

  • Helps discriminate sensory information for sound and texture

  • Malformation linked to autism

  • Note: Coordinates actions, does not cause them.

• Medulla Oblongata

  • Regulates unconscious functions like breathing and circulation.

  • Controls heartbeat, coughing, sneezing, and salivation through cranial nerves.

  • Note: Damage to the medulla oblongata can be fatal.

• Pons

  • Involved in sleep and arousal.

  • Contains several clusters of cell bodies; name means "bridge".

  • Connects the medulla with the rest of the brain, and cerebellum to the rest of the brain.

  • Controls facial expressions and plays a role in breathing.

• Reticular Formation (RF)

  • Integrates sensory processes such as vision and hearing.

  • Plays a role in eye movement.

  • Uses a lot of dopamine.

  • Contributes to modulation of muscle reflexes, breathing, and pain perception.

  • Located in the central core of the brain stem.

  • Regulates consciousness; damaged RF can lead to coma.

Midbrain

• General Functions of Midbrain

  • Integrates sensory processes, such as vision and hearing.

  • Contributes to eye movement.

  • Features significant dopamine utilization.

• Basal Ganglia

  • Composed of multiple smaller structures.

  • Plays a role in planning behavior initiation and directing movement.

• Substantia Nigra

  • Produces dopamine; involved in smooth initiation of movement.

• Ventral Tegmental Area (VTA)

  • Part of the midbrain with connections to the Nucleus Accumbens (NA).

Forebrain

• Thalamus

  • Relay center for cortex, handling incoming and outgoing signals.

  • Processes all senses except for smell.

• Cerebrum/Cerebral Cortex

  • Responsible for thinking, learning, emotion, consciousness, and voluntary movement.

  • The outer, wrinkled part is known as the cerebral cortex.

• Hypothalamus

  • Regulates biological needs: hunger, thirst, temperature control.

  • Located near the base of the forebrain, below/next to thalamus.

  • Activates "fight or flight" response.

  • Regulates 4 F's: food, fun, fight or flight, and sex.

  • Involved in sexual desire, internal temperature management, and circadian rhythms.

  • Regulates the pituitary gland and endocrine system, which involves glands and hormones.

• Pituitary Gland

  • Known as the "master" gland; regulates other endocrine glands.

  • Connected to the hypothalamus and releases growth hormones.

Limbic System

• Hippocampus

  • Associated with learning and memory.

  • Wraps around thalamus; converts short-term memory into long-term.

  • Note: Does not store memory; assembles information from various brain parts for recall.

• Amygdala

  • Involved in emotion and aggression.

  • Located at the ends of the hippocampal arm.

  • Affects feelings of anger, aggression, and fear.

  • Helps determine whether experiences are pleasurable.

• Olfactory Bulbs

  • Play a role in the limbic system.

• Cingulate Gyrus

  • Located above the corpus callosum.

  • Associates memories with smell and pain; produces positive and negative feelings.

  • Regulates maternal behavior and cognitive flexibility.

• Septum

  • Part of the limbic system.

  • Involved in rageful behavior and hypersensitivity.

• Corpus Callosum

  • A bridge of fibers that connects the two cerebral hemispheres, facilitating communication between them.

Lobes of the Cerebral Cortex

• Occipital Lobe

  • Responsible for vision and processing visual information—"eyes in the back of your head."

• Parietal Lobe

  • Registers sense of touch while integrating visual input.

  • Monitors the body's position in space.

  • Processes stimuli related to touch, pressure, temperature, and pain.

  • Contains the somatosensory cortex, specifically processing touch sensations.

• Temporal Lobe

  • Responsible for auditory processing.

  • Damage can impair comprehension of speech and language.

  • The right temporal lobe is crucial for face recognition; the left is essential for understanding spoken language.

• Frontal Lobe

  • The largest lobe, controlling movement and muscles.

  • Responsible for reasoning, planning, emotion, personality, social control, and attention.

  • Acts as the executive decision-maker; interprets information from other brain areas to decide on actions.

  • Houses the primary motor cortex (for movement messages) and the prefrontal cortex (which is the last part of the brain to develop).

Brain Plasticity

• Definition: Plasticity refers to the ability of neurons to change in structure and function.

  • The concept of "The brain is plastic" conveys:

  1. The brain can modify itself based on experience.

  2. Change and adapt as structured by life experiences (specific to the cerebral cortex).

  3. The brain can reorganize in response to damage, modifying itself structurally or biochemically.

  • Mechanisms include forming new dendrites, altered synaptic connections, and increasing neurotransmitter volume.

  • Note: As age increases, the capacity of the brain to reorganize decreases.

  • The adult brain can generate new neurons in specific areas: olfactory bulbs and the hippocampus (related to neurogenesis, which is being researched).

Language Processing Areas

• Wernicke’s Area

  • Located in the temporal lobe.

  • Responsible for understanding language.

• Broca’s Area

  • Located in the frontal lobe, next to the motor cortex affecting face and mouth movement.

  • Involved in the production of speech.

• Angular Gyrus

  • Located at the intersection of the occipital and temporal lobes.

  • Converts visual information into auditory code, allowing one to understand what they are reading (hence the phenomenon of hearing words in one’s head while reading).

• Aphasia

  • A severe language impairment affecting language comprehension or production.