is face processing species specific during the first year of life

Page 1: RNA Virus and Adaptive Antiviral Defense

  • RNA Virus and Silencing Suppressors:

    • Sophila cells exposed to an RNA virus exhibit strong viral RNA silencing.

    • The RNA virus has an effective silencing suppressor that is essential for successful infection.

  • RNA Silencing as Antiviral Defense:

    • Provides evidence that RNA silencing functions as an adaptive antiviral defense mechanism in animal cells.

    • Specified by base pairing of siRNA with target RNA, differing from peptide recognition in cellular and humoral immunity.

  • Consequences of Viral Genome Inserts:

    • Incorporating heterologous sequences into a replicating viral genome can produce siRNAs targeting related viral and cellular RNAs.

    • Research indicates that viral inserts in alphavirus vectors produce resistance in mosquitoes based on RNA sequence, not protein products.

  • Future Research Directions:

    • Investigate if RNA silencing similarly protects against mammalian viruses due to heterologous RNA expression from viral vectors.

  • References:

    • 1-24: Citation list for supporting data and methodological references related to RNA silencing and antiviral mechanisms.

Page 2: Face Processing in Infancy

  • Perceptual Narrowing:

    • Between 6-10 months, infants' discrimination of native speech improves while foreign speech discrimination declines.

    • Study investigates if this perceptual narrowing applies to face recognition, assessing both human and monkey face discrimination.

  • Infants' Discrimination Abilities:

    • 6-month-olds could discriminate faces from both species; 9-month-olds and adults focused on human faces only.

    • Implication: perceptual narrowing in face recognition mirrors language development in infants.

  • Cognitive Development in Face Recognition:

    • Early face recognition follows rapid changes in infancy followed by gradual refinement into adolescence.

    • Recognition of faces becomes species-specific due to cortical specialization from experience with faces.

  • Visual Paired-Comparison (VPC) Methodology:

    • VPC was used to assess recognition by contrasting looking times at familiar versus novel stimuli.

    • Results indicated the significant ability of younger infants to recognize both human and monkey faces.

  • Evidence of Species-Specific Processing:

    • Adults' performance indicates they are less adept at recognizing monkey faces, confirming a shift toward species familiarity.

    • Key Findings:

      • 6-month-olds: Discriminated effectively across species.

      • 9-month-olds: Show preference for human faces, consistent with studies on face processing.

Page 3: Cognitive Systems and Future Studies

  • Cognitive Systems Overlap:

    • Recognition systems for faces and speech may develop together, influenced by similar timing.

    • Early adjustments in processing faces suggest experience affects perceptual tuning.

  • Potential for Learning New Stimuli:

    • Although initial face processing narrows focus on human faces, later exposure might allow recognition of other species.

  • Further Research:

    • More developmental and comparative studies required to distinguish mechanisms underlying speech and face perception tuning.

    • Supports the hypothesis of a general perceptual tuning apparatus influenced by experience.