Brain and Behavior IB 132 – Lecture 6: Sensation, Perception, and Consciousness

Vocabulary flashcards covering sensation, perception, EEG patterns, sleep stages, memory types, and language centers based on the Brain and Behavior Lecture 6 transcript.

Selective Attention

The act of seeking out and focusing on stimuli that are momentarily important while avoiding the distraction of irrelevant stimuli.

AD/HD (Attention Deficit/Hyperactivity Disorder)

A condition characterized by abnormal difficulty in maintaining selective attention, impulsiveness, and hyperactivity; associated with dysfunction in the basal nuclei and prefrontal cortex.

Methylphenidate (Ritalin®)

A medication that increases synaptic concentrations of dopamine and norepinephrine to treat AD/HD.

Conscious Experience

The awareness of internal ideas, thoughts, and external objects/locations, residing in a set of neurons that are temporarily functioning together.

Arousal

A state of increased wakefulness, vigilance, and responsiveness of cortical and thalamic neurons to sensory stimuli, often monitored using EEG.

EEG (Electroencephalogram)

A recording of electrical signals, largely due to summed postsynaptic graded potentials, originating primarily in the pyramidal cells of the cortex.

EEG Amplitude

Measured in $mV$; a high value indicates synchrony, meaning many neurons are activated simultaneously.

EEG Frequency

Measured in $Hz$ ($\text{cycles per second}$); it ranges from $1$ to $> 40\,Hz$, where lower frequency typically indicates a less responsive state.

Epilepsy

A neurological disease associated with abnormally synchronized discharges of cerebral neurons, involuntary muscle contraction, and temporary loss of consciousness.

Alpha Rhythm

The most prominent EEG wave pattern when awake and relaxed; recorded best over parietal and occipital lobes.

Beta Rhythm

The EEG pattern that replaces alpha rhythms when a person is attentive to external stimuli or thinking hard.

Theta Rhythm

An EEG frequency range of $4$ to $8\,Hz$ that occurs as a person shifts toward sleep.

Delta Rhythm

The dominant EEG pattern in the deepest stage of NREM sleep, characterized by frequencies less than $4\,Hz$.

NREM (Non-Rapid Eye Movement) Sleep

The initial phase of sleep divided into 4 stages, featuring theta waves, sleep spindles, K complexes, and eventually delta rhythm.

REM (Rapid Eye Movement) Sleep

Also called paradoxical sleep; characterized by an EEG similar to the alert state and dreaming, though the sleeper is difficult to arouse.

Adenosine

A homeostatic regulator of sleep that binds to receptors to cause drowsiness by slowing down nerve cell activity.

Caffeine

A substance that competes with adenosine binding to its receptor, reducing its sleep-inducing effect.

Learning

The acquisition and storage of information.

Memory

The relatively permanent storage form of learned information.

Implicit (Procedural) Memory

Non-declarative memory of how to do things (e.g., riding a bike) where recall is unconscious; involves the sensorimotor cortex, basal nuclei, and cerebellum.

Explicit (Declarative) Memory

The retention and recall of conscious experiences, such as facts and events, that can be put into words; requires the hippocampus and amygdala.

Consolidation

The process by which short-term memories are converted into long-term memories.

Encoding

The first process in explicit memory involving attention to and processing of newly learned information and association with existing memories.

Retrograde Amnesia

The loss of memories for a variable period of time before a physical trauma, such as a blow to the head.

Anterograde Amnesia

A type of amnesia resulting from damage to the limbic system (hippocampus, thalamus, hypothalamus) that prevents the formation of new memories.

Coma

A severe decrease in mental function due to structural, physiological, or metabolic impairment.

Brain Death

A state where the brain no longer functions and has no possibility of functioning again.

Primary Motivated Behavior

Behavior directly related to homeostasis, such as drinking water to satisfy thirst.

Dopamine

The major neurotransmitter in the pathway mediating brain reward systems and motivation.

Psychological Dependence

A facet of substance dependence characterized by a craving for the substance and inability to stop using it at will.

Physical Dependence

A facet of substance dependence requiring the person to take the substance to avoid withdrawal symptoms.

Amygdala

A limbic system structure specifically responsible for emotional responses such as fear.

Wernicke’s Area

A region in the temporal lobe; damage leads to comprehension aphasia, where speech is fluent but words are scrambled and sense-less.

Broca’s Area

A region in the frontal cortex; damage causes expressive aphasia, where the person understands language but has trouble forming words.