The Brain: Your Crowning Glory

Lesson 2.1

The Hindbrain

the lowest and oldest part of the brain; includes the medulla, pons, and cerebellum; regulates the basic functions taht keep us alive

Medulla

conveys sensory information from the spinal cord to the forebrain; control of basic bodily processes including heart rate, breathing, and certain reflexes

Pons

conveys sensory information from the spinal cord to the forebrain; regulation of states of wakefulness and sleep

Cerebellum

responsible for regulation of balance and coordination

Forebrain

the largest and most advanced part of the brain, located at the top and front; includes the thalamus/hypothalamus, limbic system, basal ganglia, and cerebral cortex

Thalamus

relay station for sorting and integrating sensory input (except smell) via the cerebral cortex; regulation of sleep-wake cycles and voluntary movement via basal ganglia

Hypothalamus

sits below the thalamus; helps control homeostasis and regulate body temperature, hunger/thirst, sleep cycles, and emotions, as well as connects the nervous system to the endocrine (hormone) system

Limbic System

• responsible for emotional processing, motivated behavior, and learning/memory functioning

  • consists of amygdala, hippocampus, parts of the hypo/thalamus, and other nearby structures

Basal Ganglia

responsible for regulation of movement and coordination

Cerebrum

the largest part of the forebrain; consists of the left and right hemispheres, each with four types of lobes

Occipital Lobes

located in the back of the head, responsible for processing visual information

Parietal Lobes

located on the sides of the brain and include the:

Somatosensory Cortex

processes sensory information received from receptors in the skin (touch, pressure, temperature, pain, movement)

Frontal Lobes

• located in the front part of the brain; correspond to the “executive center” of the brain; involved in higher mental functioning including planning/decision making and processing emotions

• also contains the motor cortex, which controls voluntary movements

Temporal Lobes

receive and process sensory information from the ears

Corpus Callosum

allows communication between the hemispheres

Cerebral Cortex

• The thin, wrinkled outer layer covering the cerebrum

• responsible for higher mental functions (most of the cortex consists of association areas that are involved in this) including thinking, language, learning, memory, and control of voluntary movement

• makes up over 80% of the brain’s mass due to its convoluted (folded/twister) surface

The Midbrain

• located between the hindbrain and forebrain; contains pathways that link these regions and help control automatic eye movements (allowing focus on objects even as the head shifts)

• also forms part of the brainstem (specifically the reticular formation)

Reticular Formation

• a network of neurons that regulates attention, alertness, and arousal

• this system acts as a filter, screening sensory input and ensuring important information reaches higher brain centers, even during sleep