BehSci - GR1 Brain and Consciousness

3 brain divisions

-Hindbrain or older brain
-Midbrain or Limbic System
-Forebrain or Cortex

Hindbrain

-Brain stem, medulla, pons, thalamus, cerebellum
-Controls breathing, heartrate, sleeping, arousal, coordination, and balance

Midbrain

-Amygdala, hypothalamus, hippocampus
-Atop the brain stem, connects hindbrain with forebrain
-controls movement, transmits information, emotion and drive

Forebrain

4 Lobes: frontal, parietal, occipital, temporal
-manages complex cognitive activities, sensory and associative functions, voluntary motor activities
-human forebrains are extremely well developed

Medulla

(hindbrain) at the base of the brainstem, controls heartrate and breathing

Thalamus

(hindbrain) pair of egg-shaped structures that function as a sensory control center, receives information from the spinal cord and routes it to the proper place

recticular formation

(hindbrain) Nerve network extending from spinal cord up into the thalamus, transporting stimuli and information, also controls arousal

Cerebellum

(hindbrain) extends from rear of brainstem, 2 wrinkled halves, coordinates motor movement with the basal ganglia, and voluntary movement with the pons, enables non-verbal learning and memory
-contains more than half the brains neurons

Amygdala

(midbrain) two lima bean sized clusters of neurons that enable aggression and fear

Hypothalamus

(midbrain) just below the thalamus, governs bodily maintenance, hunger, thirst, body temperature, sexual arousal, maintains homeostasis, a steady internal state
-also contains the brains reward system, produces a desire for pleasure by governing pituitary gland

Hippocampus

(midbrain) curved structure that processes conscious, explicit memories, harbors the ability to form new memories of facts and events
-as we age, hippocampus becomes smaller, therefore memory declines

Cerebrum

two cerebral hemispheres, 85% of brains weight
-enables speaking, thinking, perceiving, and voluntary actions
-covered by the cerebral cortex, a thin surface layer of interconnected neural cells

Motor Cortex

an area in the rear of the frontal lobe, a thin band across the brain, each part of the motor cortex controls a specific part of the body
-right side controls left side of body, and vice versa

somatosensory cortex

parallel to and just behind the motor cortex, at the front of the parietal lobe, receives information from the skin senses, touch, temperature, and body movement

association areas

1/4 of our cortex is dedicated to sensory input and muscular output, the other 3/4 are association areas
-each lobe has its own association areas
-prefrontal cortex in frontal lobe, enables judgement, planning, social interactions, processing, and new memories

frontal lobe

speaking, making plans and movements, logic, motor cortex band at back of lobe

parietal lobe

sensory input for touch and body position, has somatosensory cortex which receives and interprets senses

Occipital lobe

visual cortex, responsible for seeing

Temporal lobe

Auditory cortex, responsible for audio

Consciousness

our subjective awareness of ourselves and movement, helps to set and achieve goals, focuses on present and future

how does consciousness arise?

It arises from coordinated and synchronized activity across the brain, must be triggered by strong activity across multiple areas of the brain

Selective attention

-our awareness only focuses on one thing at a time
-we take in about 11,000,000 bits of info per second, process about 40
-the other 11,000,000 bits are used unconsciously
-rapidly changing between activities in the enemy of focus

Inattentional blindness

Caused by focused attention elsewhere

change blindness

blind to a change in a scene after a brief attention-stealing incident

Dual processing

deliberate conscious thinking, and automatic unconscious thinking working together
-for vision, there is a visual perception track and a vision action track

% of brain activity unconscious

80-90% of brain activity is unconscious
-thinking intensely about a single thing only increases our brain activity by 5%

Parallel Processing

Mind taking care of routine business, unconscious

Sequential processing

step-by-step, solving new problems