Neuroscience Attention and memory

Attention

• Basic component of cognition

• Influences ability to direct focus

• Related to arousal and alertness

• Sustained vs. selective attention

Neural Processes of Attention

Consciousness → Neurotransmitters → Sensory Processes

Attentional Networks: 

Alerting

• Neural Structures: Thalamus, frontal, parietal regions

• Neurotransmitter: norepinephrine

• Functional Example = hearing a siren while driving or seeing the traffic light change 

• Dysfunctional example = not reacting to a loud noise

Orienting

• Neural Structures: superior parietal lobe, temporo-parietal lobe junction, frontal eye fields

• Neurotransmitter: Acetylcholine

• Functional Example = Facing and attending to people at your table when eating 

Executive Control

• Neural Structures: Anterior cingulate cortex; lateral prefrontal cortex

• Neurotransmitter: Dopamine 

• Functional Example = Planning 

Categories of Attention

• Sustained

  • Concentration, vigilance, non-distractibility

  • Function: maintain attention

  • Dysfunction: not able to maintain attention

• Shifting

  • Divided attention

  • Function: attending to multiple tasks at once (cooking)

  • Dysfunction: forget about tasks while doing others

Goal Directed Attention

• Frontal Cortex = Attention

• Parietal Cortex = Alerting

• Multimodal association areas

Memory

Brain networks that encode memory (durable memory)

- Limbic system (emotional component)

      -      Hippocampus- information from multiple cortical areas

•  Amygdala

-  Basal ganglia (learning of automatic or stereotypical movements)

-  Cerebellum (feedback and feedforward mechanisms based on prior learning and memory)

-  Cerebral hemispheres

• Right: memories and spatial patterns

•  Memories and language

-  Frontal lobe

•  Prefrontal cortex seat of STM

- Parietal, occipital, and temporal lobes

•  Storage of attributes of objects and people

Memory Encoding

• Transfer of information from STM- LTM

•  Association of novel information with that which is already learned

 Components of events

• Time, Place, People, Context, Emotions

How the brain stores information

 Memories fragmented into different areas of the brain

•  By the sound they make

•  By their actions

•  By appearance

•  The way they feel to the touch

•  The way they move

Consolidation of Memories: SLEEP!

Mnemonic Devices

 Method of loci

•  The creation of a visual image and linking it to mental location

•  Example: visual map of your house to remember what to buy at grocery store

 Acronyms

•  First letter of each word chained to a meaningful sentence

 Rhymes

• Types of poems that facilitate learning

Types of memory

Retrospective and prospective

• Recall of past events through associations

•  Retrieval of information from LTM to predict future events

Explicit and implicit

• Conscious, intentional recall of information

•  Unconscious, unintentional recall of previously learned information

Short term and long term

•  Information encountered that is limited in scope and lasts only about 15-30 seconds

•  Information from past or longer than one hour ago

Amnesia 

1. Retrograde

•  Loss of entire personal past after injury or trauma

•  LTM often resolves as brain injury resolves

2.  Anterograde

• Memory dysfunction in which a person cannot remember ongoing day-to-day events

3.  Transient global amnesia

• Loss of one’s past and ongoing day-to-day

• Onset rapid and usually clears

Emotion

Primary Structures of emotion: prefrontal cortex, limbic system, anterior cingulate

Secondary structure of emotion: Thalamus, anterior insula, Septum pellucidum

Hemispheric roles in emotion

• Right:  Prefrontal area coincides with emotions of agitation, nervousness, distress, anxiety, sadness, depression

•  Left:  Prefrontal cortex coincides with positive emotions and sense of well-being

Emotional Syndromes of Brain injury

 Left prefrontal lobe damage

•  Right hemisphere takes control

•  Leads to emotional lability, depression, despondence

 Right prefrontal lobe damage

• Indifference to impairment

• Euphoria

• Excess well-being

 Orbito frontal lobe lesions

• Impulsiveness and disinhibition due to lack of regulation of executive function

 Dorsolateral lobe lesions

•  Decreased drive and motivation, lethargy, disengagement

Amygdala and Emotion

 Role = Works with anterior cingulate, prefrontal lobe, and right hemisphere to assess danger and recognition of social-emotional cues

• Part of the pleasure center of the brain

•  Lesions lead to the loss of fear, difficulty recognizing danger, excessive risk-taking

PTSD- highly active amygdala

•  Feeling that traumatic events keep happening over and over

• Language area shuts down

•  Overwhelming somatic experience that invades consciousness

Anxiety, Panic Attacks, OCD

 Anterior Cingulate → Amygdala → Temporal Cortex

Anger and depression

 Anger- Septal area

 Depression

• Decreased activity in prefrontal cortex and ACG

• Increased activity in amygdala and hippocampus

•  Imbalance of serotonin, norepinephrine, and dopamine